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HomeMy WebLinkAboutContract 26683�►YY SECRETqRY CONTqACT Np. �p � Between C1YY 0F FORT WORTH and MATERIALS ANALY�IC�-OL ����/I�ES, I NC. (MAS) For LABORATORY SERVICES RELATING TO PROJECT XL PHASE I f_ .��_��. ..�..�_. ; � r t p n.` r^ �t r ;i � � � � � U�j��� ��Ii; ��'� � �`���f���llc�� ,� . r � r,`rJ i � i' ?�b�. c'L� r UC�L� �1�It�icU ` `: , ' n i''1� + . �.. . , .. . . . .. ^ H.._p � DEPARTMENT OF ENVIRONMENTAL MANAGEMENTA MARCH, 2001 City of Fort Worth, 7'exas �9�A�ar And aun�;l an�n�un�cAt�an e c DATE REFERENCE NUMBER LOG NAME PAGE 3/27/01 **C-18519 52LAB 1 of 2 sua�ECT APPROPRIATION ORDINANCE AND AWARD OF CONTRACT TO MATERIALS ANALYTICAL SERVICES, INC. FOR ENVIRONMENTAL LABORATORY SERVICES FOR PROJECT XL RECOMMENDATION: It is recommended that the City Councii: 1. Approve the transfer of $25,000 in undesignated funds in the Environmental Management Operating Fund to the XL Project in the Environmental Management Project Fund; and 2. Adopt the attached appropriation ordinance increasing estimated receipts and appropriations in the Environmental Project Fund in the amount of $25,000 from available funds; and 3. Authorize the City Manager to execute a contract with Materials Analytical Services, Inc. for environmental laboratory services at a total cost not to exceed $25,000 in connection with Project XL. DISCUSSION: Project XL stands for "eXcellence and Leadership", and was created in March 1995 as part of the Reinventing Environmental Regulation initiatives. XL projects are real world tests of innovative strategies that achieve cleaner, more cost-effective results than traditional regulatory approaches. Each project that is accepted into the program involves the granting of regulatory flexibility by the Environmental Protection Agency (EPA) in exchange for an enforceable commitment by a community to achieve better environmental results than would have been attained through full compliance with existing or anticipated future regulations. In recent years, the City has been waging a stepped up war on urban blight through enforcement of building maintenance codes and through special emphasis on property redevelopment and sustainable community issues. The City submitted its Project XL proposal to the EPA in September 1999. The proposal, entitled "Asbestns Management in the Demolition of Substandard Structures as a Nuisance Abatement," sought regulatory flexibility from the EPA to proceed with the demolition of substandard structures that are not in danger of imminent collapse without prior removal of regulated asbestos containing material. In January 2000, THE EPA issued a conditional letter of selection. On September 29, 2000, in a ceremony at City Hall, an agreement was signed by the City of Fort Worth, the Texas Department of Health, and the Environmental Protection Agency to begin Phase I of the City's XL project. In February 2001, the City received EPA approval to use 2615 Ennis Avenue as the site for Phase I demolition. Materials Analytical Services, Inc. (MAS) was selected to perform laboratory services because they are one of the few laboratories in the United States that have relevant experience performing the analyses needed for this project. In addition, no Texas Department of Health licensed laboratories were found to have the experience and expertise fdr the required work. MAS has a current National Voluntary Laboratory Accreditation Program Certification necessary for the project. MAS has experience working with both the EPA and state governments on similar projects, and has performed satisfactorily on those projects. __ _ . __ _ __ _ _ _ City of Fo�t Worth, Texas �11�A�ar A11d auncil afrrtm�nac�►tian C � DATE REFERENCE NUMBER LOG NAME PAGE 3/27/01 **C-18519 52LAB 2 ofi 2 suB�ECT APPROPRIATION ORDINANCE AND AW�RD OF CONTRACT TO MATERIALS ANALYTICAL SERVICES, INC. FOR ENVIRONMENTAL LABORATORY SERVICES FOR PROJECT XL The provisions in Chapter 252 of the Texas Local Government Code do not apply because it is a "procurement necessary to preserve or protect the public health or safety of the municipality's residents." FISCAL INFORMATION/CERTIFICATION: The Finance Director certifies that upon approval of recommendation No. 1 and adoption of the attached appropriation ordinance, funds will be available in the current capital budget, as appropriated, of the Environmental Management Project Fund. CB:k , _ __ _ _ _ _ __ _. __ _. __ _ Submitted for City Manager's FUND ACCOUNT CENTER AMOUNT CITY SECRETARY Office by: (to) _ 2) R101 531060 052200110000 $25,000.00 _ �P�R�vE� Charles Boswell 8511 Originating Department Head: ' . /'1'�� CO' (A'(��� \.� v�vv . . ; Brian Boerner 8079 (from) , MAR 2"� 2��� 1) R103 538070 0521100 $25,000.00 /' Additional Information Contact: 3) R101 531060 052200110000 $25,000.00 (fjp�„L ���� �"�, -- Brian Boerner gp�g City Sc�crstary of the City of Foxt �'arth, Tara� _ . Adoptecl Ordinanc� No, ���: �ON RACT�Np YO7�p � �� STATE OF TEXAS KNOW ALL PERSONS BY THESE PRESENTS COUNTY OF TARRANT CONTRACT BETWEEN THE CITY OF FORT WORTH, TEXAS, AND MATERIALS ANALYTICAL SERVICES, INC. (MAS) FOR LABORATORY SERVICES RELATING TO PROJECT XL PHASE I This agreement is entered into by and between the City of Fort Worth, Texas, a home-rule municipal corporation situated in Tarrant and Denton Counties, Texas, hereinafter called "City," acting herein through Charles Boswell, its duly authorized Assistant City Manager, and Materials Analytical Services, Inc. (MAS), hereinafter called "Contracto�;" by and through �, • , ` , its duly authorized �j���� .r� ��� In consideration of the mutual promises and benefits of this contract, the City and Contractor agree as follows: 1. TERM This contract shall be effective from the date of its execution by both parties, until the completion of all Contractor services as provided in Section 2, or for a period not to exceed one (1) year from date of execution, whichever occurs first. 2. SCOPE OF CONTRACTOR'S SERVICES A. Contractor shall provide on an as needed basis, all the labor, materials, and equipment necessary for performing laboratory analysis of air, soil, and water samples taken by or for City in Phase I of City's Project XL project. Analysis shall be accomplished utilizing the following methods: 1 2. � TEM air analysis in accordance with ISO Method 10312:1995 Water analysis in accordance with EPA Method for the Determination of Asbestos Fibers in Water Soil analysis in accordance with EPA Standard Operating Procedure for the . Screening Analysis of Soil and Sediment Samples for Asbestos Content Contract between the City Of Fort Worth, Texas, and Materials Analytical Services, Inc. (MAS) For laboratory services relating to Project XL Phase I ';��Gr����OG�� �'�CJ�� '� ���1� d���� USL� l�%a�1 U �o �r��) "���6 ��}�a Page 1 4. Water (Moisture) content analysis in accordance with ASTM Standard Test Method D 4959-00 Determination of Water (Moisture) Content of Soil by Direct Heating B. Contractor shall forward analytical results to the City within 10 business days of sample receipt. C. Contractor shall perform its seivices in a good and professional manner. Contractor shall adhere to the provisions of the Quality Assurance Project Plan (QAPP) applicable to laboratory services. A copy of the QAPP is attached hereto as Appendix A, and incorporated fully into this contract. D. Contractor shall provide City with all sample containers, preservatives, and returnable shipping containers necessary for this project, if required by MAS. E. Contractor's handling instructions and chain-of-custody protocols shall be in accordance with all Federal and State statutes and regulations for laboratory methods and quality assurance. F. Contractor shall be responsible for the disposal of the samples and such disposal shall be in accordance with all federal and state statutes and regulations. G. Contractor agrees that it shall maintain during the term of this contract, current and appropriate federal, state, and local licenses and permits to perfortn the services contained in this contract. H. Contractor agrees that it shall not subcontract any of the services to be provided to City, without first obtaining written permission from City to do so. Subcontractors shall be held to the same requirements of this contract that pertain to Contractor. 3. CITY'S RESPONSIBILITIES A. City shall designate a City representative to provide timely direction to the Contractor and render City decisions. B. City shall be responsible for collecting samples or having sample collected, and shipping them to Contractor. ��;�����c0 ,�,�� �?���QD 4. �: Ofi' ����� � � ° f��l COMPENSATION „- -���a �'Uf G'��lp � �.��-- -� Contract between the City Of Fort Worth, Texas, and Materials Analytical Services, Inc. (MAS) For laboratory services relating to Project XL Phase I Page 2 A. In consideration for the work performed by Contractor under this contract, City shall pay Contractor a sum not to exceed twenty-five thousand dollars ($25,000.00). Payment shall be based on the unit price charges as set forth below: 1. TEM air analysis in accordance with ISO Method 10312:1995 =$350 per sample 2. Water analysis in accordance with EPA Method for the Determination of Asbestos Fibers in Water =$250 per sample. 3. Soil analysis in accordance with EPA Standard Operating Procedure for the Screening Analysis of Soil and Sediment Samples for Asbestos Content =$250 per sample. 4. Water (Moisture) content analysis in accordance with ASTM Standard Test Method D 4959-00 Determination of Water (Moisture) Content of Soil by Direct Heating = $50 per sample. B. City shall make payment within thirty (30) days of receiving a correct invoice from Contractor. City is responsible for notifying Contractor of any questions concerning an invoice. In the event of a disputed or contested billing, only that portion so contested will be withheld from payment, and the iuldisputed portion will be paid. The City will exercise reasonableness in contesting any bill or portion thereof. No interest will accrue on any contested portion of the billing until muhially resolved. C. Contractor shall receive no compensation for delays or hindrances to the work, except when direct and unavoidable extra cost to Contractor was caused by City's failure to provide information, if any, which it is required to do. When extra compensation is claimed, a written statement thereof shall be presented to the City. 5. INSURANCE The Contractor certifies it has, at a minimum, current insurance coverage as detailed below and will maintain it throughout the terms of this contract. Prior to commencing work, the Contractor shall deliver to City, certificates documenting this coverage. The City may elect to have the Contractor submit its entire policy for inspection. � : Commercial General Liabilitv Insurance -$1,000,000.00 per occurrence Automobile Liabilitv Insurance -$1,000,000.00 per accident 1. This policy shall include pollution coverage; that is, it shall not have the pollution exclusion. Plus, the policy shall cover loading, unloading and transporting materials collected under this contract. Contract between the City Of Fort Worth, Texas, and Materials Analytical Services, Inc. (MAS) For laboratory services relating to Project XL Phase I ��'u'�G���; �J���l�,. �'��U�i� D 7� ^ I� ���) � ��� � U �I� ����:; Uc����i;�ll;f,�l � �1�� �nrJ�:'�Ir� ��I�'�a �_ Q �. _ Page 3 C. Worker's Compensation Insurance - Statutory limits, plus employer's liability at a minimum of $ 500,000.00 each accident; $ 500,000.00 disease - policy limit; and $ 500,000.00 disease - each employee. D. Environmental Im�airment Liability�EILI and/or Pollution LiabilitX -$1,000,000.00 per occurrence. Coverage must be included in policies listed in items A and B above; or, such insurance shall be provided under separate policy(s). Liability for damage occurring while loading, unloading and transporting materials collected under the contract project shall be included under the Automobile Liability insurance or other policy(s). NOTE: BETWEEN A AND D ABOVE, ANY POLLUTION EXPOSURE, INCLUDING ENVIRONMENTAL IMPAIRMENT LIABILITY, ASSOCIATED WITH THE SERVICES AND OPERATIONS PERFORMED UNDER THIS CONTRACT SHALL BE COVERED; IN ADDITION TO SUDDEN AND ACCIDENTAL CONTAMINATION OR POLLUTION LIABILITY FOR GRADUAL EMISSIONS, CLEANUP COSTS SHALL BE COVERED. E. The following shall pertain to all applicable policies of insurance listed above: Additional Insured Endorsement: "The City of Fort Worth, its officers, agents, employees, representatives, and volunteers are added as additional insureds as respects operations and activities of, or on behalf of the named insured, performed under contract with the City of Fort Worth." Reasonably equivalent terms may be acceptable at the sole discretion of the City of Fort Worth. 2. Subcontractors shall be covered under the Contractor's insurance policies or they shall provide their own insurance coverage; and, in the latter case, documentation of coverage shall be submitted to the Contractor prior to the commencement of worlc and the Contractor shall deliver such to the City. 3. Prior to commencing worlc under the contract, the Contractor shall deliver to the City of Fort Worth insurance certificate(s) documenting the insurance required and terms and clauses required. 4. Each insurance policy required by this agreement shall contain the following clauses: "This insurance shall not be canceled, limited in scope or coverage, or non-renewed until after thirty (30) days prior written notice has been given to the Director of Environmental Management, City of Fort Worth, 1000 Throckmorton, Fort Worth, Texas 76102." 5. The insurers for all policies must be approved to do business in the State of Texas and be currently rated in terms of financial strength and solvency to the satisfaction of the Director of Risk Management for the City of Fort Worth. The City's standard is an A. M. Best Key rating A:VII. c:ontract beriveen the City Of Fort Worth, Texas, and Materials Analytical Services, Inc. (MAS) For laboratory services relating to Project XL Phase I ��:;��C���O�;':� G'����D '� lU ur ���'' �������� �,f?�o �'�!}i )����IlUl�p r�F7�e l L� 11 Page 4 I1 5. The insurers for all policies must be approved to do business in the State of Texas and be currently rated in terms of financial strength and solvency to the satisfaction of the Director of Risk Management for the City of Fort Worth. The City's standard is an A. M. Best Key rating A:VII. 6. The deductible or self-insured retention (SIR) affecting the coverage required shall be acceptable to the Risk Manager of the City of Fort Worth; and, in lieu of traditional insurance, alternative coverage maintained through insurance pools or risk relations groups must be also approved." � 6. INDEMNIFICATION For purposes of this contract, the phrases "Environmental Damages" and "Environmental Requirements" shall be defined as stated below: 1. Environmental Damages shall mean all claims, judgments, damages, losses, penalties, iines, liabilities (including strict liability), encumbrances, liens, costs, and expenses of investigation and defense of any claim, whether or not such claim is ultimately defeated, and of any good faith settlement or judgment, of whatever kind or nature, contingent or otherwise, matured or unmatured, foreseeable or unforeseeable, including without limitation reasonable attorney's fees and disbursements and consultant's fees, any of which are incurred as a result of handling, collection, transportation, storage, disposal, treatment, recovery, and/or reuse of waste pursuant to this contract, or the existence of a violation of environmental requirements pertaining to, and including without limitation: a. Damages for personal injury and death, or injury to properiy or natural resources; b. Fees incurred for the services of attorneys, consultants, contractors, experts, laboratories and all other costs in connection with the investigation or remediation of such wastes or violation of environmental requirements including, but not limited to, the preparation of any feasibility studies or reports of the performance of any cleanup, remediation, removal, response, abatement, containment, closure, restoration or monitoring work required by any federal, state or local governmental agency or political subdivision, or otherwise expended in connection with the existence of such wastes or violations of environmental requirements, and including without limitation any attorney's fees, costs and expenses incurred in enforcing this contract or collecting any sums due hereunder; and Contract between the City Of Fort Worth, Texas, and Materials Analytical Services, Inc. (MAS) For laboratory services relating to Project XL Phase I ,��:�������'��,� C��:GUG'n,, �.,,�5 F '� �i�'uf � C��:: �'i� i � G�1i G�a �''ru��;"��, �C�i�o Page 5 I� C�' c. Liability to any third person or governmental agency to indemnify such person or agency for costs expended in connection with this Agreement. 2. Environmental requirements shall mean all applicable present and future statutes, regulations, rules, ordinances, codes, licenses, pertnits, orders, approvals, plans, authorizations, concessions, franchises, and similar items, of all governmental agencies, departments, commissions, boards, bureaus, or instrumentalities of the United States, states, and political subdivisions thereof and all applicable judicial, administrative, and regulatory decrees, judgments, and orders relating to the protection of human health or the environment, including without limitation: a. All requirements, including, but not limited to, those pertaining to reporting, licensing, permitting, investigation, and remediation of emissions, discharges, releases, or threatened releases of hazardous materials, pollutants, contaminants or hazardous or toxic substances, materials, or wastes whether solid, liquid, or gaseous in nature, into the air, surface water, groundwater, storm water, or land, or relating to the manufacture, processing, distribution, use, treatment, storage, disposal, transport, or handling of pollutants, contaminants, or hazardous or toxic substances, materials, or wastes, whether solid, liquid, or gaseous in nature; and b. All requirements pertaining to the protection of the health and safety of employees or the public. General Indemnification: CONTRACTOR DOES HEREBY RELEASE, INDEMNIFY, REIMBURSE, DEFEND, AND HOLD HARMLESS THE CITY, ITS OFFICERS, AGENTS, EMPLOYEES AND VOLUNTEERS, FROM AND AGAINST ANY AND ALL LIABILITY, CLAIMS, SUITS, DEMANDS, OR CAUSES OF ACTIONS WHICH MAY ARISE DUE TO ANY LOSS OR DAMAGE TO PERSONAL PROPERTY, OR PERSONAL INJURY, AND/OR DEATH OCCURRING AS A CONSEQUENCE OF THE PERFORMANCE OF THIS CONTRACT, WHEN SUCH INJURIES, DEATH, OR DAMAGES ARE CAUSED BY THE SOLE NEGLIGENCE OF CONTRACTOR, ITS OFFICERS, AGENTS, OR EMPLOYEES, OR THE JOINT NEGLIGENCE OF CONTRACTOR, ITS OFFICERS, AGENTS, OR EMPLOYEES, AND ANY OTHER PERSON OR ENTITY. Environmental Indemnification: CONTRACTOR DOES HEREBY RELEASE, INDEMNIFY, DEFEND, REIMBURSE, AND HOLD HARMLESS THE CITY, ITS OFFICERS, AGENTS, EMPLOYEES AND VOLUNTEERS, AGAINST ANY AND ALL Contract between the City Of Fort Worth, Texas, and Materials Analytical Services, Inc. (MAS) For laboratory services relating to Project XL Phase I �''��r�;'� Ct'��_� [�_'� G�� °�� ��ii�'��( ������'���C� '��� ���1j�^;��`'�'iJ� ��`� , �..y�,�, ..: , r, p U n Page 6 ;I ENVIRONMENTAL DAMAGES AND THE VIOLATION OF ANY AND ALL ENVIRONMENTAL REQUIREMENTS RESULTING FROM THE HANDLING, TESTING, STORAGE, DISPOSAL, TREATMENT, RECOVERY, AND/OR REUSE, BY ANY PERSON, OF SAMPLES, AS A CONSEQUENCE OF THE PERFORMANCE OF THIS CONTRACT, WHEN SUCH DAMAGES OR VIOLATIONS ARE CAUSED BY THE SOLE NEGLIGENCE OF CONTRACTOR, ITS OFFICERS, AGENTS, OR EMPLOYEES, OR THE JOINT NEGLIGENCE OF CONTRACTOR, ITS OFFICERS, AGENTS, OR EMPLOYEES, AND ANY OTHER PERSON OR ENTITY. D. The obligations of the Contractor under this section shall include, but not be limited to, the burden and expense of defending all claims, suits and administrative proceedings (with counsel reasonably approved by City), even if such claims, suits or proceedings are groundless, false, or fraudulent, and conducting all negotiations of any description, and paying and discharging, when and as the same become due, any and all judgments, penalties or other sums due against such indemnified persons. E. Upon learning of a claim, lawsuit, or other liability that Contractor is required hereunder to indemnify City, City shall provide Contractor with reasonably timely notice of same. F. The obligations of the Contractor under this section shall survive the expiration of this Agreement and the discharge of all other obligations owed by the parties to each other hereunder. G. In all of its contracts with subcontractors for the performance of any work under this contract, Contractor shall require the subcontractors to indemnify the City in a manner consistent with this section. H. In the event City receives a written claim for damages against the Contractor or its subcontractors prior to final payment, final payment shall not be made until Contractor either submits to City satisfactory evidence that the claim has been settled and/or a release from the claimant involved, or provides City with a letter from Contractor's liability insurance carrier that the claim has been referred to the insurance carrier. 7. WARRANTY Contractor warrants that it understands the currently known hazards and suspected hazards that are present to persons, property and the environment by providing laboratory services. Contractor further warrants that it will perform all services under this contract in a safe, efficient and lawful manner using industry accepted practices, and in full compliance with all applicable state and federal laws governing its activities. Contractor also warrants that it is under no restraint or order that would prohibit performance of services under this contract. Contract between the City Of Fort Worth, Texas, and Materials Analytical Services, Inc. (MAS) For laboratory services relating to Project XL Phase I ,�:,'�l�i�il��:uG�l� G;f�!��!�JI�'I r^ �l ��� c,��� G���t �u�G��1� �: � Il C' .: ��, � a �� �Inr,.�1)�� �� ,�o ,,.;. ����9 ���l��h �� J� U�'`, J Page 7 8. TERMINATION A. City may terminate this contract, with or without cause, by giving 30 days written notice to Contractor, provided that such termination shall be without prejudice to any other remedy the City may have. In the event of tertnination, any work in progress will continue to completion unless specified otherwise in the notice of termination. B. If the City terminates this contract under paragraph A of this section, City shall pay Contractor for all services performed prior to the termination notice. C. All completed or partially completed original documents prepared under this contract shall become the property of the City when the contract is terminated, and may be used by the City in any manner it desires; provided, however, that the Contractor shall not be liable for the use of such documents for any purpose other than as described when requested. D. In the event either party defaults in the performance of any of its obligations under this contract, misrepresents to the other a material fact, or fails to notify the other parly of any material fact which would affect the party's performance of its obligations hereunder, the non-defaulting party shall have a right to terminate this contract upon giving the defaulting party written notice describing the breach or omission in reasonable detail. The defaulting party shall have a thirty (30) day period commencing upon the date of notice of default in which to effect a cure. If the defaulting party fails to effect a cure within the aforesaid thirty (30) day period, or if the default cannot be cured, the contract shall terminate as of the date provided in the notice of default. 9. DEFAULT A. Contractor shall not be deemed to be in default because of any failure to perform under this contract, if the failure arises from causes beyond the control and without the fault or negligence of Contractor. Such causes shall include acts of God, acts of the public enemy, acts of Government, in either its sovereign or contractual capacity, fires, flood, epidemics, quarantine restrictions, strikes, freight embargoes, and unusually severe weather. B. If at any time during the term of this contract the work of Contractor fails to meet the specifications of the contract, City may notify Contractor of the deficiency in writing. Failure of Contractor to correct such deficiency and complete the work required under this contract to the satisfaction of City within ten days after written notification shall result in termination of this contract. Contractor shall pay all costs and attorneys fees incurred by City in the enforcement of any provision of this contract. Contract between the City Of Fort Worth, Texas, and Materials Analytical Services, Inc. (MAS) For laboratory services relating to Project XL Phase I � �i�ii�'��i���UL'-�I`� �`'isG'����<� '� Vl� ���'' �'1���� �'�ii 11 L'a �1� 1���,'�I'��D ����o Il Page 8 C. The remedies provided for herein are in addition to any other remedies available to City elsewhere in this contract. 10. RIGHT TO AUDIT A. Contractor agrees that the City shall, until the expiration of three (3) years after fmal payment under this contract, have access to and the right to examine and photocopy any directly pertinent books, documents, papers and records of the Contractor involving transactions relating to this contract. Contractor agrees that the City shall have access during normal warking hours to all necessary Contractor facilities and shall be provided adequate and appropriate workspace in order to conduct audits in compliance with the provisions of this section. The City shall give Contractor reasonable advance notice of intended audits. B. Contractor further agrees to include in all its subcontractor agreements hereunder a provision to the effect that the subcontractor agrees that the City shall, until the expiration of three (3) years after final payment under the subcontract, have access to and the right to examine and photocopy any directly pertinent books, documents, papers a�d records of such subcontractor, involving transactions to the subcontract, and further, that the City shall have access during normal working hours to all subcontractor facilities, and shall be provided adequate and appropriate work space, in order to conduct audits in compliance with the provisions of this article together with subsection C. hereof. City shall give subcontractor reasonable advance notice of intended audits. C. Contractor and subcontractor agree to photocopy such documents as may be requested by the City. The City agrees to reimburse Contractor and/or subcontractor for the cost of copies at the rate published in the Texas Administrative Code in effect as of the time copying is performed 11. INDEPENDENT CONTRACTOR It is understood and agreed by the parties hereto that Contractor shall perform all work and services hereunder as an independent contractor, and not as an officer, agent, servant or employee of the City. Contractor shall have exclusive control of and the exclusive control of and the exclusive right to control the details of all the work and services performed hereunder, and all persons performing same, and shall be solely responsible for the acts and omissions of its officers, agents, servants, employees, contractors, subcontractors, licensees and invitees. The doctrine of respondeat superior shall not apply as between City and Contractor, its officers, agents, employees, contractors and subcontractors, and nothing herein shall be construed as creating a partnership or joint enterprise between City and Contactor. Contract between the City Of Fort Worth, Texas, and l'J_,i��'IJ"� ll%`;_�, U�(��l��V'f�'�11J Materials Analytical Services, Inc. (MAS j,?�jT��i �;�,,i� ("��i���'���rr)'�UI For laboratory services relating to Project XL Phase I � U U o�. z� 9< <� uir Uu '� Page 9 ��a V���`�'f�=IU�UUo Ul`��Ua 12. NON-DISCRIMINATION A. During the performance of this contract, Contractor agrees not to discriminate against any employee or applicant for employment because of race, religion, color, sex or national origin, except where religion, sex or national origin is a bona fide occupational qualification reasonably necessary to the normal operation of the Contractor. Contractor agrees to post in conspicuous places, available to employees and applicants for employment, notices setting forth the provisions of the non-discrimination clause. B. Contractor also agrees that in all solicitations or advertisements for employees placed by or on behalf of this contract, that Contractor is an equal opportunity employer. C. Notices, advertisements, and solicitations placed in accordance with federal law, rule or regulation shall be deemed sufficient for the purpose of ineeting the requirements of this section. 13. GOVERNING LAW The City and Contractor agree that the laws of the State of Texas shall govern the validity and construction of this contract, except where preempted by federal law. 14. RIGHTS AND REMEDIES NOT WAIVED In no event shall the making by the City of any payment to Contractor constitute or be construed as a waiver by the City of any breach of covenant, or any default which may then exist, on the part of Contractor, and the making of any such payment by the City while any such breach or default exists shall in no way impair or prejudice any right or remedy available to the City with respect to such breach or default. Any waiver by either party of any provision or condition of the contract shall not be construed or decreed to be a waiver of any other provision or condition of this contract, nor a waiver of a subsequent breach of the same provision or condition, unless such waiver is expressed in writing and signed by the party to be bound. ;���G����;��i� G�-_'���cuG�D � ,`;/ ^ , ,' �5'�' � n'��'� ��: � U C����::��t�i��;\,U� Contract between the City Of Fort Worth, Texas, and � �' Ij� ��"��� 'I ��� � il i�p �� �<<;�q �� Materials Analytical Services, Inc. (MAS) ! = -•�— - - �--- For laboratory services relating to Project XL Phase I Page 10 15. ENTIRETY This contract and any other documents incorporated by reference herein contain all the terms and conditions agreed to by the City and Contractor, and no other contracts, oral or otherwise, regarding the subject matter of this contract or any part thereof shall have any validity or bind any of the parties hereto. 16. ASSIGNMENT The City and Contractor bind themselves and any successors and assigns to this contract. Contractor shall not assign, sublet, or transfer its interest in this contract without written consent of the City. Nothing herein shall be construed as creating any personal liability on the part of any officer or agent of the City, nor shall it be construed as giving any rights or benefits hereunder to anyone other than the City and Contractor. 17. NOTICE Notices required to be made under this contract shall be sent to the following persons at the following addresses; provided, however, that each party reserves the right to change its designated person for notice, upon written notice to the other party of such change: If to City: Written notice shall be sent to: Brian Boerner, Director Department of Environmental Management 1000 Throckmorton Fort Worth, Texas 76102 If to Contractor: Questions should be directed to: Michael Gange, Environmental Supervisor Department of Environmental Management 1000 Throckmorton Fort Worth, Texas 76102 (817) 871-8504 / Fax (817) 871-6359 � Name: {� i. ��� v/�'I G� ti�' C�I���:� �,; ��C.Q� c. Materials Analytical Services, Inc. (MAS) � 3945 Lakefield Court Suwanee, Georgia 30024 (770) 866-3200 / Fax (770) 866-3259 Contract between the City Of Fort Worth, Texas, and Materials Analytical Services, Inc. (MAS) For laboratory services relating to Project XL Phase I '::!!�(���"�'°'�,�� ��[���R@ � ��� �� �l ��� ������'a �� � ;Ni,�; �`��r�;;�;Cr�l�1 ll�/.�n t._ -_��_�� h:ii,��f� Page 11 18. VENUE Should any action, real or asserted, at law or in equity, arise out of the terms and conditions of this contract, venue for said action shall be in Tarrant County, Texas. 19. SEVERABILITY The provisions of this contract are severable; and if for any reason any one or more of the provisions contained herein are held to be invalid, illegal or unenforceable in any respect, the invalidity, illegality or unenforceability shall not affect any other provision of this contract, and this contract shall remain in effect and be construed as if the invalid, illegal or unenforceable provision had never been contained in the contract. 20. MODIFICATION No modification of the contract shall be binding on Contractor or City unless set out in writing and signed by both parties. 21. AUTHORIZATION The undersigned officer and/or agents of the parties hereto are properly authorized officials and have the necessary authority to execute this contract on behalf of the parties hereto, and each party hereby certifies to the other that any necessary resolutions extending such authority have been duly passed and are now in full force and effect. Contract between the City Of Fort Worth, Texas, and Materials Analytical Services, Inc. (MAS) For laboratory services relating to Project XL Phase I i��[��D���Q� �[��C��� co� �����c�?c�Q� G��_ hr:,�����_�i����l� ��{� � Page 12 � IN WITNESS WHEREOF, the parties hereto have executed this agreement in triplicate originals in Fort Worth, Tarrant County, Texas. � City of Fort Worth Materials Analytical Services, Inc. ,� _`` Charles Boswell, Assistant City Manager Name: ir �. Co�. �.e� Title: �" � � �-. Date: � % Date: �C-/.> = C% / --, Approved as to Form and Legality: G ��� City Attorney Witness• . �♦ '' ��Z �' j }t��,, / : ;' 'r'' � ��-! �_ _, r� '.Narrie•:.•�i'.,'�•�� �r ' •:�:i'tte: �C�� `;���' �� �' �-��/`%J1��7l��7`,��Z'��L_ Att Corporate Seal: "1 � � � - P ��� ��-}-f = i/� =� ��J 19��� � �i Gloria Pearson, City Secretary 7° �+ Z - � - /�� �9 eontract Authorization �-� �'� �i' - 0/ Date Contract between the Cit}� Of Fort Worth, Texas, and Materials Analytical Services, Inc. (MAS) For laboratory services relating to Project XL Phase I c����cDa� ��i�CC��� C��'� ������: G��� �',� U�o U'' l�Il1: I�,� i� r U l��do ,, - XLPHILABv.S Page 13 Meeting America's Needs for Experrenced and Comprehensive Environmental Management Q�p Section A August 17, 2000 Revision 1 Page 1 of 30 QUALITY ASSURANCE PROJECT PLAN AMBIENT AIR MONITORING FOR ASBESTOS DURING DEMOLITION OF SUBSTANDARD STRUCTURES IN CTTY OF FORT WORTH, TEXAS (PROJECT XL) Prepared by: Environmental Quality Management, Inc. 1310 Kemper Meadow Drive, Suite 100 Cincinnati, Ohio 45240 Prepared for: City of Fort Worth Department of Environmental Management 1000 Throckmorton Street Fort Worth, Texas 76102-6311 Section � QAPP Section A June 2, 2000 Revision 0 Page 4 of 30 A2 TABLE OF CONTENTS Pa�e Project Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 of 30 Al Title and Approval Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , A2Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A3 Distribution List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A4 Project Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A.4.1 City of Fort Worth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A4.2 Industrial Hygiene & Safety Technology, Inc . . . . . . . . . . . . . . . . A4.3 Microscopy Laboratory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A4.4 Demolition Contractor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AS Problem Definition/Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A5.1 Background ........................................ A5.2 Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A6 Project Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A.6.1 Technical Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A.6.1.1 Demolition of Buildings . . . . . . . . . . . . . . . . . . . . . . . A.6.1.2 Air Sampling During Demolition of Buildings ...... A.6.1.3 Air Sampling During Landfilling of Demolition Debris A.6.2 Personnel .......................................... A.6.3 Project Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A7 Quality Objectives and Criteria for Measurement Data . . . . . . . . . . . . . . A7.1 Primary Project Objective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A7.2 Criteria for Acceptance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A7.3 Statistical Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A7.4 Precision and Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A7.5 Completeness .. .. .... . . . . . .. . . . . .. . . . . . .. . . .. . . . .. . . A7.6 Representativeness ....... ........... ...... ........... A7.7 Comparability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A7.8 Analytical Sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A8 Special Training Requirements/Certification . . . . . . . . . . . . . . . . . . . . . . A8.1 Field Personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A$.2 Laboratory Personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A9 Documentation and Records . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A9.1 Field Operations Records . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A.9.1.1 Air Sample Documentation . . . . . . . . . . . . . . . . . . . . A.9.1.2 Meteorological Measurements . . . . . . . . . . . . . . . . . . A.9.1.3 Photo Documentation . . . . . . . . . . . . . . . . . . . . . . . . A9.2 Chain-of-Custody Records . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 of 30 . 4 of 30 10 of 30 11 of 30 11 of 30 13 of 30 13 of 30 13 of 30 14 of 30 14 of 30 15 of 30 16 of 30 16 of 30 17 of 30 17 of 30 18 of 30 18 of 30 18 of 30 20 of 30 20 of 30 20 of 30 20 of 30 22 of 30 22 of 30 23 of 30 23 of 30 23 of 30 25 of 30 25 of 30 25 of 30 26 of 30 26 of 30 26 of 30 26 of 30 29 of 30 29 of 30 A2 TABLE OF CONTENTS (continued) Section Q�P Section A August 17, 2000 Revision 1 Page 5 of 30 Pa�e A9.3 Laboratory Records . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 of 30 � A.9.3.1 TEM Specimen Examination and Data Recording ... 29 of 30 A.9.3.2 Test Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 of 30 B Measurement/Data Acquisition . . . . . . . a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 of 28 Bl Sampling Design ........................................... B.l.l Sampling Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B.1.2 Air Sampling Strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B.1.3 Particulate Loading Pilot Test . . . . . . . . . . . . . . . . . . . . . . . . . . . B.1.4 SoilSampling ....................................... B.1.5 Moisture Content of ACM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B.1.6 Water Used for Wetting Structure/Debris . . . . . . . . . . . . . . . . . . B2 Sampling Methods Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B.2.1 Air Sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B.2.2 Meteorological Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B.2.3 Soil Sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B.2.4 Water Sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3 Sample Custody Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B.3.1 Field Chain-of-Custody . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B.3.2 Laboratory ......................................... B4 Analytical Methods Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B.4.1 AirSamples ........................................ B.4.1.1 TEM Specimens Preparation . . . . . . . . . . . . . . . . . . . B.4.1.2 Measurement Strategy . . . . . . . . . . . . . . . . . . . . . . . . B.4.2 Soil Samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B.4.3 Moisture Content of ACM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B.4.4 Water Samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BS Quality Control Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B.5.1 Field Quality Control Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . B.5.2 Analytical Quality Control Checks . . . . . . . . . . . . . . . . . . . . . . . . B.5.2.1 Quality Control Check of Filter Media . . . . . . . . . . . . B.5.2.2 Blank Contamination . . . . . . . . . . . . . . . . . . . . . . . . . B.5.3 Analytical Precision and Accuracy . . . . . . . . . . . . . . . . . . . . . . . . B.5.3.1 Replicate Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . B.5.3.2 Duplicate Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . B.5.4 Verification Counting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 of 28 , 1 of 28 , 1 of 28 . 6 of 28 , 6 of 28 . 7 of 28 . 7 of 28 8 of 28 8 of 28 S of 28 10 of 28 10 of 28 12 of 28 12 of 28 12 of 28 14 of 28 14 of 28 14 of 28 14 of 28 16 of 28 16 of 28 16 of 28 17 of 28 17 of 28 17 of 28 17 of 28 18 of 28 19 of 28 19 of 28 20 of 28 21 of 28 Section A2 TABLE OF CONTENTS (continued) QAPP Section A August 17, 2000 Revision 1 Page 6 of 30 Pa e B6 Instrument/Equipment Testing, Inspection, and Maintenance Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 of 28 B.6.1 Field Instrumentation/Equipment : . . . . . . . . . . . . . . . . . . . . . . . . 22 of 28 B.6.2 Laboratory Instrumentation/Equipment . . . . . . . . . . . . . . . . . . . . 22 of 28 B7 Instrument Calibration and Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 of 28 B.7.1 Field Instrument/Equipment Calibration . . . . . . . . . . . . . . . . . . . 23 of 28 B.7.1.1 Air Sampling Pumps . . . . . . . . . . . . . . . . . . . . . . . . . 23 of 28 B.7.1.2 Airflow Calibration Procedure . . . . . . . . . . . . . . . . . . 23 of 28 B.7.2 Calibration of TEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 of 28 B8 Inspection/Acceptance Requirements for Supplies and Consumables .... 25 of 28 B.8.1 Air Sampling Filter Media . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 of 28 B9 Data Acquisition Requirements (Non-direct Measurements) . . . . . . . . . . 26 of 28 B.9.1 Precision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 of 28 B.9.2 Completeness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 of 28 B.9.3 Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 of 28 B 10 Data Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 of 28 B.10.1 Data Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 of 28 B.10.2 Data Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 of 28 B.10.3 Statistical Analysis . . . : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 of 28 C Assessment/Oversight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 of 4 Cl Assessments and Response Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 of 4 C.1.1 Performance and System Audits . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 of 4 C. l.l.l Field Audits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 of 4 C.1.1.2 Laboratory Audit . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 of 4 C.1.2 Corrective Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 of 4 C2 Reports to Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 of 4 D Data Validation and Usability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 of 3 D1 Data Review, Validation, and Verification Requirements . . . . . . . . . . . . . . 1 of 3 D2 Validation and Verification Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 of 3 D3 Reconciliation with Data Quality Objectives . . . . . . . . . . . . . . . . . . . . . . . . 3 of 3 EReferences ...................................................... lofl Appendices A I: C � E Q�P Section A August 17, 2000 Revision 1 Page 7 of 30 A2 TABLE OF CONTENT5 (continued) Comparison of the Asbestos NESHAP and the Fort Worth Method for the Demolition of Substandard Structures ISO Method 10312:1995. Ambient Air - Determination of Asbestos Fibres -- Direct-Transfer Transmission Electron Microscopy Method Standard Operating Procedure for the Screening Analysis of Soil and Sediment Samples for Asbestos Content ASTM Standard Test Method D 4959-00. Determination of Water (Moisture) Content of Soil by Direct Heating EPA Method 100.1 Analytical Method for the Determination of Asbestos Fibers in Water QAPP Section A August 17, 2000 Revision 1 Page 8 of 30 FIGURES Number Pa�e A-1 Project Organization . . . . : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 of 30 A-2 Project Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 of 30 A-3 Sampling Data Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 of 30 A-4 Meteorological Measurement Log . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 of 30 B-1 Wind Rose for June, City of Forth Worth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 of 28 B-2 Analytical Request and Chain-of-Custody Form . . . . . . . . . . . . . . . . . . . . . . . . 13 of 28 C-1 Corrective Action Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 of 4 � QAPP Section A August 17, 2000 Revision 1 Page 9 of 30 TABLES Number Pa�e A-1 Effect of Number of Days of Demolition or Land Filling and Between-Sample Variation on Statistical Power Calculations Assuming 5 Samples Upwind and 5 Samples Downwind from the Site . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 of 30 B-1 Air Sampling Strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 of 28 B-2 Approximate Number of Grid Openings to Achieve Target Analytical Sensitivity Based on Air Volume of 3000 Liters (Direct-Transfer Preparation of TEM Specimens) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 of 28 Q�p Section A June 2, 2000 Revision 0 Page 10 of 30 A3 DISTRIBUTION LIST Brian Boerner, Environmental Management Division, City of Fort Worth, Texas Kathryn A. Hansen, Environmental Management Division, City of Fort Worth, Texas Michael A. Gange, Environmental Management Division, City of Fort Worth, Texas Shirley Hoover, Environmental Management Division, City of Fort Worth, Texas Mike Camp, Code Compliance, Department of City Services, City of Fort Worth, Texas Brian Haggerty, City Manager's Office, City of Fort Worth, Texas Charles Boswell, Assistant City Manager, City of Fort Worth, Texas Adele Cardenas, U.S. EPA, Region VI Todd Wingler, Texas Department of Health Roger C. Wilmoth, National Risk Management Research Laboratory (NRMRL), U.S. EPA Tracy K. Bramlett, Industrial Hygiene & Safety Technology, Inc. Demolition Contractor (To Be Determined) Microscopy Laboratory (To Be Determined) QAPP Section A August 17, 2000 Revision 1 Page 11 of 30 A4 PROJECT ORGANIZATION Environmental Quality Management, Inc. (EQ) has been contracted by the City of Fort Worth, Texas, to design this Quality Assurance Project Plan (QAPP).1 The QAPP was prepared to meet U.S. Environmental Protection Agency (EPA) requirements applying to projects that include environmental measurements and is written in the format specified by EPA.�I� The project organization chart showing the relationships and the lines of communication among project participants is contained in Figure A-1. A.4.1 City of Fort Worth Brian Boerner, CHMIvI, will serve as the Program Manager. He has overall administrative and technical responsibility for the project. Kathryn A. Hansen, Esquire, will serve as the Project Manager. She has overall administrative responsibility for the project. As such, she will resolve any administrative problems that may occur and serve as the administrative contact with the Texas Department of Health, U.S. EPA, Industrial Hygiene & Safety Technology, Microscopy Laboratory (To Be Determined), Demolition Contractor (To Be Determined), and others. Michael A. Gange will serve as the Technical Project Officer. He has overall technical responsibility for the project. He will ensure that Industrial Hygiene & Safety Technology, Inc. Mr. Kominsky (Vice President/Director Industrial Hygiene & Safety, EQ) prepared this QAPP. He has more than 25 years of experience in the comprehensive practice of industrial hygiene and safety, of which 13 years were with the National Ins[itute for Occupational Safety and Health (NIOSI�. Since 1988, he has designed, implemented, and served as Project Manager/Principal Investigator on more than 15 asbestos research projects for EPA's National Risk Management Research Laboratory (NRMRL). Five studies (4 EPA and 1 commercial client) involved the determination of ambient concentrations of airborne asbestos in communities during demolition of buildings containing asbestos-containing materials (AC1Vn and landfill of the resultant asbestos- containing demolition debris, and other such projects involving fugitive emissions of asbestos. Mr. Kominsky has a Master's of Science Degree in Industriat Hygiene (University of Pittsburgh, 1973) and Bachelor of Science Degree in Chemical Engineering (University of Nebraska, 1971). He is a Certified Industrial Hygienist by the American Boazd of Industrial Hygiene, a Certified Safety Professional by the American Board of Certified Safety Professionals, and a Certified (Master Level) Hazardous Materials Manager by the Institute of Hazardous Materials Management. He is an Adjunct Associate Professor in the Department of Environmental Health at the University of Cincinnati. He has authored or co-authored more than 35 journal articles (11 articles related to asbestos) regazding occupational, environmental, and pubiic heaith. s = s u o �- C '�n a a > � m " = N 0 ,�,. o0 O � � � � � � O> p � ���u� E�� �� �� o u`n p. � N � O 0~��� N = � W � X -c F- U i ° c � � � � � a �� oa > � n U � � � o a � O � � a� r� W LL � +_ � m � ° � .� c > cp V ° w `� m` � 0 a w � i i � i i i i ^______L_____^ I I � �- O 0 0 0� '� � ° � �-aa� Q d p � �U w � U v vi�Xc� � Q -t u c 0 m U> � } o a, � � _o 0 Z��o, � d U O � w � � � � � ' � `n � � � N U c a� � c � U O O .N a � 3� ���� u o .? p o0 � o a o ° _ � � r� I.L N �- •� �p �!.- N C � O � � � O i� .� :�' N Q � o0 U a � w � � �•.. '� o N � Q � � C '� � O � �' U o � � W a o �o � m c c � � 6 � v � c C � p N 't a o c c .- �°�_ ° a�� o.�a C Cco >,o ��.°� r_ � Z' � > fp U � o W � ° o � � � � `o N s � 3 � Q�� 0 o-<n � r� Q � � �O � o�U ��i� u- (_j � �° o w O a� � � � I� :�'U � U cnoo U �, a U G N � � � rn � ° o �� a,Z ac� O � o Q� v�'� 3 ��� o� 't •°� c r- 0 0 Q � ar n t+-�— c Eao � O o s � o � +T. 'c � p '> cp �.. G -� U���i, o a � 0 QAPP Section A June 2, 2000 Revision 0 Page 12 of 30 � � oZf � U � 0 c �; = o `n a� rnU .mv. '�o $ �� S c °' � � s E—v a � o � F� m O.. N N � "U I� > >[ C O` c o a a N F� � c a a a o� c U � � c m op »- a� o °Q O N �-- � o ..., aa � � p ,c .a J N Q � o �, y m � � <V `- < � 0 � C� N .� CCi bA 1. � �i�+ U d .� a � � � b�JD F�+ Q�p Section A August 17, 2000 Revision 1 Page 13 of 30 (IHST) implements the study in strict accordance with the QAPP and that the demolition contractor (To Se Determined) follows the Fort Worth Method. As such, he will resolve any technical difficulties with the contractors. He will also be responsible for resolving any technical difficulties associated with the laboratory analysis of the samples, data analysis and management, and preparation of the final project report. A.4.2 Industrial Hygiene & Safety Technology, Inc. Project Manager/Principal Investigator -- Mr. Tracy K. Bramlett (President, Industrial Hygiene & Safety Technology, Inc.) will serve as the Project Manager/Principal Investigator and maintain close communication with Ms. Hansen, Mr. Gange, and the demolition contractor. He will ensure that all IHST project personnel fully understand and strictly adhere to the QAPP. All IHST technical team members will be experienced professionals who possess the degree of specialization and technical competence required to effectively perform the required work. Mr. Bramlett will coordinate and supervise implementation of the QAPP including site preparation, sample collection and documentation, data management and analysis, and preparation of the project report. He will coordinate the sampling staff, ensure all equipment is calibrated properly and measurements are made in accordance with the QAPP, review and validate field data (e.g., sampling data logs), review sample custody and traceability records, and coordinate submission of the samples to the laboratory. He will ensure that any problems or potential deviations from the QAPP reported by any of the project staff are addressed immediately and receive corrective and documented action, as necessary. Prior to effecting any deviations from the approved QAPP, the potential deviation will be discussed with and approval to deviate will be obtained from Mr. Gange. A.4.3 Microscopy Laboratory (To Be Determined) Laboratory will perform the transmission electron microscopy (TEM) analysis of all samples collected. A.4.4 Demolition Contractor (To Be Determined) Demolition contractor will perform the demolition of the facilities. AS PROBLEM DEFINITION/BACKGROUND A.5.1 Background QAPP Section A June 2, 2000 Revision 0 Page 14 of 30 In order to demolish substandard structures2 that are not in danger of imminent collapse, the City of Fort Worth currently follows the requirements established by Asbestos National Emissions Standards for Hazardous Air Pollutants (NESHAP), 40 CFR §61.145. The City of Fort Worth proposes an alternative method, hereinafter referred to as the Fort Worth Method, for the demolition of "facilities" in lieu of the current Asbestos NESHAP requirements for the demolition of substandard structures that are not in imminent danger of collapse. If left standing, the substandard facilities will within several years become structurally unsound. Instead of waiting for these buildings to reach such a structural state, the City proposes to be proactive and demonstrate that facilities with regulated asbestos-containing material (RACM) left in-place is at least as protective as demolition of buildings with the RACM removed.3 Based on the condition of the RACM, demolishing facilities while in substandard condition most likely is more protective of the public and environment than demolishing such facilities in danger of uruivnent danger of collapse. Due to the requirements of Asbestos NESHAP, the City has only demolished facilities with RACM remaining in place when the facility is in unminent danger of collapse. Preliminary data generated by both phase contrast microscopy (PCM) and transmission electron microscopy (TEM) indicates that demolition of such structures using the Fort Worth Method does not generate significant airborne fiber levels.�2� The Fort Worth Method's one primary difference from the existing Asbestos NESHAP is handling of the RACM. Prior to and during the course of demolition the facility is thoroughly wetted and demolition proceeds in a manner that allows the non-asbestos-containing building In the City of Fort Worth, a structure is considered substandard when it does not meet the sEandards or specifications established in the City's Minimum Building Standards Code, Ordinance No. 13743. The City of Fort Worth proposes to demolish a facility without removal of RACM with certain exceptions. Spray-applied fireproofing and large quantities of thermal system insulation (>260 linear feet) will be removed using full-containment abatement procedures. Q�P Section A June 2, 2000 Revision 0 Page 15 of 30 material (ACBM) to act as a banier between the ACBM and the environment. By proper handling and wetting of the demolition debris, asbestos fiber release is controlled. A comparison of the Asbestos NESHAP and the Fort Worth Method is contained in Appendix A. The Fof-t Worth Method's primary goal is to protect the public and the environment from the release of asbestos during the demolition of buildings containing in-place RACM. It's secondary goal is to provide a alternative method for controlling asbestos that creates a cost savings for municipalities performing demolition of nuisance buildings. A.5.2 Objectives The primary objectives of this project are: 2. Determine whether the airborne concentrations of asbestos upwind (comparative environmental backgroasnd4) during demolition of buildings containing in-place RACM are statistically significantly different than those concentrations downwind. 3. Determine whether the airborne concentrations of asbestos upwind (comparatzve environmental backgrounc� during land filling of building demolition contauung RACM are statistically significantly different than those concentrations downwind. Environmental background is the airborne concentration of asbestos prevailing in this area that is upgradient (upwind) from the facilities being demolished or the demolition debris being landfilled. QAPP Section A August 17, 2000 Revision 1 Page 16 of 30 A6 PROJECT DESCRIPTION A.6.1 Technical Approach The project will be performed in two phases: Phase I and Phase II. Phase I--Phase I will gather data on the Fort Worth Method's ability to prevent or minimi�e the release of asbestos fibers during demolition of buildings that are either exempt from the Asbestos NESHAP requirements (residential buildings that have four or fewer dwelling units) or not subject to asbestos NESHAP.S The data from Phase I will be analyzed to determine whether the Fort Worth Method is equivalent to the NESHAP method; i.e., the airborne concentrations of asbestos upwind (comparative environmental backgroun� during demolition of the facilities and land filling of the resultant demolition debris are not statistically significantly different than the respective concentrations downwind. If the Phase I data supports a finding that the Fort Wor�th Method is equivalent to the Asbestos NESHAP method, the City will proceed with Phase II. If the methods are not found to be equivalent, the project may end with Phase I. Phase II--Phase II will gather data on various buildings subject to the Asbestos NESHAP. These buildings will include single or two-story commercial structures and/or multi-family residential structures. The ACBM that are likely to be present include, but not limited to resilient floor tile and mastic, Transite� panels, roofing materials, wallboard joint compound, wall and ceiling texture, thermal system insulation, and miscellaneous other materials. Prior to demolition of a structure, a thorough asbestos assessment of the facility will be conducted by a State of Texas Department of Health licensed Asbestos Inspector. The assessment will identify the type, quantity, location, and condition of ACBM. Prior to demolition of the.facility, spray-applied fueproofing or large amounts of thermal system insulation will be removed by a State of Texas Department of Health licensed Asbestos Abatement Contractor. The type and quantity of ACBM remaining in the facility will be documented. Asbestos NESHAP regulations must be followed for demolitions of facilities with at least 260 linear feet of RACM on pipes, 160 square feet of RACM on other facility components, or at least 35 cubic feet off facility components where the amount of RACM previously removed from pipes and other facility components could not be measured before stripping. Q�'P Section A August 17, 2000 Revision 1 Page 17 of 30 A.6.1.1 Demolition of Buildings The buildings will be demolished using heavy equipment only. A typical building demolition will include the following: One or more bulldozers for single-story buildings, and a combination of bulldozers, front-end loader, and track-hoes for multi-story buildings. Thoroughly and adequately wetting the structure using fire hydrant water applied with a variable rate 11-G (11 gpm) or 30-G (30 gpm) nozzle prior to, during demolition, and during debris loading. A water meter (or equivalent device) will be installed at the water hydrant to measure the volume of water used during demolition of the structure. The water will be delivered as a mist or concentrated stream. Direct high-pressure water impact of ACM will be prohibited.6 The demolition debris will be adequately wet at all times and kept wet during handling loading into containers for transport to a licensed disposal site. Collapsing structures inward (majority of the walls and interior components will be leveled on top of the building foundation) and loading debris prior to removal of the concrete slab, if present. • Segregation of demolition debris to the extent feasible to reduce the amount of contaminated debris that will be treated as asbestos-contaminated waste. Debris not contaminated by the ACBM will be treated as construction debris, while all other materials will be treated as asbestos-contaminated waste. The RACM debris will be transported to a licensed disposal site in lined and covered containers. Segregation of the waste will be the responsibility of an onsite Asbestos NESHAP trained individual. Grading of the site for future use. A.6.1.2 Air 5ampling During Demolition of Buildings The first study objective (see Section A.5.2) will be addressed by collecting ambient air samples at ten locations for three to five consecutive days during demolition of a facility. Five sampling locations will be located both upwind (comparative environmental background level of asbestos) and downwind of the demolition area. Meteorological conditions (such as wind Although experience demonstrates that building demolition projects typically have a minimal to moderate amount of water runoff depending on the site locations and site conditions, the City will utilize Best Management Practices to control water runoff and collect storm water on the project site. Storm drain inlet protection will be used in conjunction with on-site controls (such as natural and marunade drainage channels), as necessary. QAPP Section A August 17, 2000 Revision 1 Page 18 of 30 direction and wind speed) will be determined explicitly to establish and ensure true upwind and downwind conditions during sampling (see Section B.1.1). A.61.3 Air Sampling During Land Filling of Demolition Debris The second study objective (see Section A.5.2) will be addressed by collecting ambient air samples at ten locations for two to three consecutive days during land filling of the demolition debris from each facility. The projected monitoring of two to three consecutive days during landfilling of the demolition debris is based on the amount of time required to landfill the debris from a given site. Five sampling locations will be located both upwind (comparative environmental background level of asbestos) and downwind of the land fill. Meteorological conditions (such as wind direction and wind speed) will be determined explicitly to establish and ensure true upwind and downwind conditions during sampling (see Section B. L 1). A.6.2 Personnel The environmental measurements (field samples and meteorological measurements) will be made by and at the direction of an ABIH-Certified Industrial Hygienist, Tracy Bramlett. He has more than 23 years of experience in the comprehensive practice of industrial hygiene with approxirnately 21 years of asbestos monitoring experience including ambient air monitoring for asbestos and licensed appropriately by the State of Texas as an air monitoring technician. Other field personnel will include industrial hygienists experienced in asbestos ambient air monitoring and related measurements. A.6.3 Project Schedule The tentative project schedule is presented in Figure A-2. The major activities are listed sequentially, and the expected duration of each activity is presented. Q�P Section A August 17, 2000 Revision 1 Page 19 of 30 QAPP Section A June 2, 2000 Revision 0 Page 20 of 30 A7 QUALITY OBJECTIVES AND CRITERIA FOR MEASUREMENT DATA The overall quality assurance objective of this project is to implement procedures for field sampling, chain-of-custody, laboratory analysis, and reporting that will provide data to satisfy the Primary Project Objective (i.e., the objective that will lead to the development of scientifically valid conclusions in the final report). Specific procedures for sampling, chain-of-custody, laboratory analysis, field and laboratory audits, preventive maintenance of field equipment, and corrective actions are described in other sections of this QAPP. A.7.1 Primary Project Objective The primary project objective is to determine the concentrations of airborne asbestos upwind (comparative environmental backgrounc� and those concentrations that are present downwind of the demolition site and the demolition debris land fill. A.7.3 Criteria for Acceptance The criteria for acceptance of equivalency of the Fort Worth Method to the e�sting Asbestos NESHAPS Method will be achieved by meeting either of the following: There is not a statistically signif'icant difference in the airborne concentrations of asbestos upwind during demolition of buildings containing in-place RACM or upwind during land filling of this building demolition debris compared to those concentrations measured downwind of the respective sites. The statistical comparisons will be made at the 0.05 level of significance. 2. The downwind sample average is less than 70 asbestos structures per square milluneter; the AHERA (40 CFR 763) clearance criterion. A.7.3 Statistical Power The study is designed to detect a 5-fold difference in average concentration (e.g., a 5-fold difference between the airborne asbestos concentrations upwind and downwind from the demolition or land filling sites) with high probability if such a difference actually e�sts. A false- Q�P Section A August 1'7, 2000 Revision 1 Page 21 of 30 positive error rate' of 5 percent will be achieved by employing a statistical significance level of 0.05 (i.e., a confidence level of 95%). A false-positive error occurs if we determine that a significant difference between the upwind and downwind airborne asbestos concentrations exists when, in fact, it did not. The statistical power of the upwind-downwind comparison will depend on the number of days required to demolish the building or landfill the demolition debris (Table A-1). Assuming three days of demolition per facility and ten air samples collected each day (five locations upwind, five location downwind), a simple parametric comparison (e.g., t-test) between the upwind and downwind locations will have a false-negative error rate8 of approxirnately 10% for a 5-fold difference between mean concentrations and approximately 1% for a 10-fold Table A-1. Effect of Number of Days of Demolition or Land Filling and Between-Sampte Variation on Statistical Power Calculations Assuming 5 Samples Upwind and 5 Samples Downwind from the Site Number of Coefficient of Variation, % Days Difference 100 150 200 250 2-fold 0.42 0.28 0.16 0.17 2 days 5-fold 0.98 0.85 0.78 0.68 10-fold >0.99 0.99 0.95 0.93 2-fold 0.62 0.41 0.26 0.26 3 days 5-fold 0.99 0.98 0.95 0.89 10-fold >0.99 >0.99 0.99 0.99 2-fold 0.74 0.52 0.41 0.33 4 days 5-fold >0.99 0.99 0.97 0.95 10-fold >0.99 >0.99 >0.99 >0.99 A false-positive error rate is the probability of rejecting the null hypothesis when the null hypothesis is actually true. A false-negative error rate is the probability of accepting the null hypothesis when the null hypothesis is actually false. QAPP Section A June 2, 2000 Revision 0 Page 22 of 30 difference (or equivalently, there is a probability of 0.90 of detecting a 5-fold difference and a probability of approximately 0.99 of detecting a 10-fold difference between mean concentrations at the upwind and downwind locations). A false-negative error occurs if we determine that no difference in airborne asbestos concentration e}cists, when in fact the concentrations did differ. The probability estima.tes assume a between-sample coefficient of variation (CV) of 250 percent, which is environmentally conservative, and were estimated by Monte Carlo simulation using log-normal random variables. Under more optimistic assumptions regarding the variability of ineasurements (e.g., a between-sample CV of 150 percent), the probability of detecting a 5-fold difference between the mean airborne asbestos concentrations upwind and downwind using a simple comparison (e.g., t-test) would be increased to approximately 98 percent. A.7.4 Precision and Accuracy The estimated false-negative error rates assume a between-sample coefficient of variation of 250 percent. This assumption is reasonable and environmentally conservative, and is based on measured concentrations of asbestos in ambient air at other locations.�3�5� The between-sample coefficient of variation is influenced by heterogeneity in the air being measured as well as sampling and laboratory performance used to collect and analyze the samples, respectively. If the overall target precision is not achieved, the false-negative error rate will increase. The data will ultimately be analyzed using analysis of variance (ANOVA) methods, rather than simple t-tests. The ANOVA methods will provide additional statistical power in detecting differences between sampling locations and, consequently, the false-negative error rates are expected to be lower than those stated in Section A.7.2. In addition, duplicate field samples will be collected during each day of sampling and compared to results from co-located samples to evaluate the precision as well as serve as a combined check on the sample collection and analysis procedures. A.7.5 Completeness An overall measure of completeness will be given by the percentage of samples specified in the sampling design that yield usable "valid" data. Although every effort will be made to collect and analyze all of the samples specified in the sample design, the sample design is robust to Q�P Section A June 2, 2000 Revision 0 Page 23 of 30 sample loss. The loss of a small number of samples, provided that they are not concentrated at a single sampling site, will likely have little effect on the false-negative error rate. The project goal is to collect at least 95 percent of the samples specified in the sample design. A.7.6 Representativeness The sampling locations, sampling periods, and sample durations have been selected to assure reasonable representativeness. The five upwind sampling locations will be selected as locations that can be reasonably viewed as representing comparative environmental background conditions that are unaffected or influenced by activities of the demolition and land filling operations. The five downwind sampling locations will be selected as representative sites that would be influenced by potentially significant releases of asbestos from the demolition or demolition debris land filling operations. Samples will be collected each day (meteorological conditions permitting) of the demolition or land filling of demolition debris to provide estimates that are representative of the normal meteorological conditions in the area and to account for the potential day-to-day variability associated with ambient levels of airborne asbestos. A.7.7 Comparability Data collection using standard sampling and analytical methods (e.g., ISO Method 10312:1995, counting structures longer than and shorter than 5�cm in length, and PCM equivalent fibers9) maximizes fhe comparability of the results with both past sampling results (if such e�st) and future sampling results. A.7.8 Analytical Sensitivity We have selected an analytical sensitivity (i.e., the concentration corresponding to the finding of one asbestos structure during a sample analysis) that corresponds to asbestos concentrations representative of general background concentrations in many areas of the United States. Data presented in Berman and Chatfield�6� indicate that an analytical sensitivity of 0.0005 A PCM (phase contrast microscopy) equivalent fiber is a fiber with an aspect ratio greater than or equal to 3:1, longer than 5�cm, and which has a diameter between 0.2 ,um and 3.0 �cm. Q�P Section A June 2, 2000 Revision 0 Page 24 of 30 structure/cubic centimeters of air (s/cm3) is likely sufficient to detect environmental background concentrations in many areas of the United States. The analytical sensitivity selected for the ambient air monitoring is 0.0005 s/cm3 for all asbestos structures (ininunum length of 0.5 �cm) and 0.0001 s/cm3 for asbestos structures longer than 5,um (all widths). See Section B.4 "Analytical Method Requirements." Thus, the number of ineasurements (upwind and downwind) in which asbestos structures is not observed or detected among the data collected should be minimal. Q�P Section A June 2, 2000 Revision 0 Page 25 of 30 A8 SPECIAL TRAINING REQUIl2EMENTS/CERTIFICATION A.8.1 Field Personnel The sampling (including equipment calibration, sample collection, and documentation) will be performed by and/or at the direction of an ABIH-Certified Industrial Hygienist (T. Bramlett). He has more than 23 years of experience in the comprehensive practice of industrial hygiene with appro�mately 21 years of asbestos monitoring experience including ambient air monitoring for asbestos. Other field personnel will include industrial hygienists experienced in asbestos ambient air monitoring and related measurements. A.8.2 Laboratory Personnel (To Be Determined) Laboratory is accredited by the National Institute of Standards and Technology (1VIST) National Voluntary Laboratory Accreditation Program (NVLAP) to perform Airborne Asbestos Fiber Analysis. (To Be Determined ) laboratory's NVLAP Laboratory Code No. is XXX (effective through X��X, 2000). QAPP Section A June 2, 2000 Revision 0 Page 26 of 30 A9 DOCUMENTATION AND RECORDS A.9.1 Field Operations Records A.9.1.1 Air Sample Documentation The following information will be recarded on a Sampling Data Form (Figure A-3): • Names of persons collecting the sample • Date of record • S ampling site • Location of sample • Type of sample (e.g., high volume, duplicate, field blank) • Unique sample number (identifies site, sample type, date, and sequence number) •� Rotameter number and air flow reading (start/stop) • Linear regression equation and correlation coefficient for the calibrated rotameter • Sample time (start/stop) • Relevant notes describing site observations such as, but not limited to site conditions, demolition method/techniques and equipment, water application nozzle and hose diameter, water application technique (spray or concentrated stream) and approxirriate amount of time (e.g., hours) for each will be recorded on the reverse side of the Sampling Data Form (and on supplemental pages, as necessary). The upwind and downwind air sampling locations will be identified on a drawing of the demolition site or land fill area. At the end of each day, the samples which were collected and the corresponding data forms/drawings will be submitted to Tracy Bramlett. He will verify the data/information for completeness; any corrections will be noted and initialed on the form. A.9.1.2 Meteorological Measurements Meteorological measurements (wind direction, wind speed, relative humidity, and temperature) will be recorded on a Meteorologic Data Measurement Log (Figure A-4). 0 � � a� � C/? cd a.� cd Q WJ � . .-� � � � C'd � QAPP Section A June 2, 2000 Revision 0 Page 27 of 30 v � y 0 V i _, V � � '� C �. � � 0 o .. .. .. .. .. .. .. .. .. .. .. Y � u � ..p t"' � u � �" V u .. .. .. .. .. .. .. .. .. .. .. � cn ..0 C.J � > ¢ � � � a �y O 3 v' 0 w L N N �O c G Q � N C'-. O .� u '=' a� � � N � � C f° U C O .� O � a 0 .� � .� U 6y1 � � � � � � � �� �M O u � (� O � E �, 0 w .� � A bA � t�, � >e�0 vl Mi � L b�i0 � QAPP Section A June 2, 2000 Revision 0 Page 28 of 30 �'��TWo� =�= Weather Station Measurement Log 5��: Dacc _ f / Page: of Investigawr. TIME �ND WIND BAROME'T2IC TEMPERAT(JRE, REIAT'lyg SPEED, MPH DIREC!'ION PRFSSURE, In. Hg °F HUMIDTIY, % Figure A-4. Meteorological Measurement Log. QAPP Section A August 17, 2000 Revision 1 Page 29 of 30 A.9.1.3 Photo Documentation A 35-mm photograph or digitized image will be taken of every sampling site. This will include the sampling station, visual debris on or in the soil. A 5-in. by 7-in. index card listing the sample number will be photographed to identify the sample and location. Other photographs or digitized images will be taken as necessary to thoroughly document the site conditions (such as "visible emissions," if such occurs) and activities. In addition, a camcorder will be used to videotape the demolition and demolition debris land filling operations. A.9.2 Chain-of-Custody Records Standard EQ sample traceability procedures described in Section B3 "Sample Custody Requirements" will be used to ensure sample traceability. A.9.3 Laboratory Records A.9.3.1 TEM Specimen Examination and Data Recording Structure counting data shall be recorded on farms equivalent to the example shown in ISO 10312:1995 contained in Append� B. A.9.3.2 Test Report The test report shall contain items (a) to (p) as specified in Section 11 "Test Report" of ISO 10312:1995. In addition, the files containing the raw data, in Microsoft Excel format, shall be submitted. The format of these files shall be as directed by the project manager, but shall contain the following items: l. Laboratory Sample Number 2. Project Sampie Number (4 Blank Lines For Project Manager to Insert Locations and Sampling Details) 3. Date of Analysis 4. Air Volume 5. Active Area of Sample Filter 6. Counting Magnification 7. Mean Grid Opening Dimension in mm 8. Number of Grid Openings Examined 9. Number of Primary Structures Detected QAPP Section A August 17, 2000 Revision 1 Page 30 of 30 10. One line of data for each structure, containing the following information as indicated in Figure 7`Bxample of Format for Reporting Structure Counting Data" of IS O 10312:1995, with the exception that the lengths and widths are to be reported in millimeters as observed on the screen at the counting magnification: • Grid Opening Number • Grid Identification • Grid Opening Identification/Address • Structure or Sub-structure Number • Asbestos Type (Chrysotile or Amphibole) • Morphological Type of Structure • Length of Structure in millimeters in 1 mm increments (e.g., 32) • Width of Structure in miltimeters in 0.2 mm increments (e.g., 3.2) • Any Other Comments Concerning Structure (e.g., partly obscured by grid bar) .�1 B MEASUREMENT/DATA ACQUISITION B1 SAMPLING DESIGN B.l.l Sampling Locations QAPP Section B A.ugust 17, 2000 Revision 1 Page 1 of 28 Ambient air samples will be collected at 10 sampling locations each day of the demolition and each day that the respective demolition debris is placed in the landiill. Five sampling locations will be located both upwind (comparative environmental background level of asbestos) and downwind of the land fill. A wind rose for five years (1988 through 1992) of June winds (0000 to 2300 hours) is presented in Figure B-1. When considering a wind fetch of 135 degrees (from the southeast) through 202.5 degrees (from the south southwest), about 54 percent of the total hours of wind data over five months of June winds were from this 67.5 degree sector. Should the wind direction change outside of this 67 degree sector for more than a 60-minute period, the sampling will be terminated. B.1.2 Air Sampling Strategy The air sampling strategy is summarized in Table B-1. Air sampling will be conducted for 3-5 and 2-3 consecutive days during demolition and land filling of the demolition debris, respectively, if acceptable meteorological conditions e�st. Acceptable meteorologic conditions include consistent upwind conditions for the environmental comparative background samples and no rain. Two sets of air samples will be collected at each sampling locations: a high-volume and a low-volume sample. A high-volume sample will be collected to achieve the target air volume (such as 3,000 liters) over the period of the demolition or land filling activities, and a second sample (low-volume) will be collected to achieve one-half of the target air volume over the same period. The second sample will be collected in the event that the first sample with the higher air volume is overloaded with particulate,'° which would preclude transmission electron microscopy lo The direct transfer analytical method (ISO 10312:1995) should not be used if the general particulate loading of the sample collection filter exceeds approximately 10 �cg/cm2 of filter surface, which corresponds to approximately 10 percent coverage of the collection filter by particulate. Q�P Section B August 17, 2000 Revision 1 Page 2 of 28 WIND ROSE PLOT STATION #03927 - DALLAS/FORT WORTH/REGIONAL AR, TX . ' NORTH � - , ' - ` - . • �. 25% ,� ' ' �,20% . ' , . � � i5ib �, �, • ,� ,� .� � t0io `, , , � � � , . 5/ � . � � � WEST � � -, - • - - , . _ . . , • - , • - • - � - - - • �- - - - - , - - - -� , , , , � , , EAST� � 'SOUTH . Wind Speed (Knols) MODEIER G.Schewe >21 DISPIAY 17-21 Wind Speed it-16 �. �� AVG. WIND SPEED a - s $•63 Knots 7•3 ORIENTATION Direction (blowing from} DATE 4/8/00 UNIT Knots CALM WINDS 6.17% PLOT YEAR-DATE-TIME 88 89 90 91 92 June 1 - June 30 Midnight -11 PM COMPANYNAME EQ COMMENTS PROJECT/PLOT NO. Figure B-l. Wind Rose for June, City of Fort Worth. QAPP Section B August 17, 2000 Revision 1 Page 3 of 28 TABLE B-1. AIR SAMPLING STRATEGY Q�P Section B August 17, 2000 Revision 1 Page 4 of 28 TABLE B-1(continued) Q�P Section B August 17, 2000 Revision 1 Page 5 of 28 TABLE B-1(continued) (TEM) analysis using the direct transfer method of sample preparation; otherwise, the second sample will be archived. Duplicate "Co-Located" Samples -- Two high-volume duplicate air samples (one upwind, one downwind) will be collected during each day of sampling. Each high-volume duplicate sample will be analyzed. Field Blanks -- Two open and two closed field blanks will be collected each day of sampling. Open field blanks are filter cassettes, that have been transported to the sampling site, opened for a short-time (< 30 seconds) without any air having passed through the filter, and then sent to the laboratory. Closed field blanks are filter cassettes that have been transported to the sampling site and then sent to the laboratory without being opened. The two open field blanks will be analyzed and the closed field blanks will be archived. The closed field blanks will only be analyzed if the open field blanks show asbestos contamination. QAPP Section B August 17, 2000 Revision 1 Page 6 of 28 B.1.3 Particulate Loading Pilot Test One of the biggest difficulties associated with ambient air monitoring is the paramount requirement to achieve adequate analytical sensitivity with constraints placed on sampling and analysis. Briefly, analytical sensitivity is a function of the volume of air passed through a filter, the concentration or dilution attendant to filter preparation, and the area of the filter scanned for analysis. The volume of air that can be collected is primarily limited by the tolerable loading of total particulate collected per unit area of filter before the sample is unsuitable for analysis by the direct-transfer TEM method because of overloading. A pilot sampling test will be performed to estimate the maximum sample air volume (with an acceptable particulate loading) to achieve the specified analytical sensitivity by counting the fewest grid openings. The pilot test will consist of collecting five sets of ambient air samples over an approxunately 6-hour period to achieve the following total air volumes: 3500, 3000, 2500, 2000, and 1500 liters. The sample will be examined by an experienced electron microscopist to determine if the particulate loading of the sample exceeds the criterion specified in ISO Method 10312:1995. B.1.4 Soil Sampling The Asbestos content of the soil will be determined both before and after demolition of the structure. Two samples will be collected from each side of the structure yielding a total of eight samples before and eight samples after demolition of each building. The sampling locations will be randomly selected from a 5-ft by 5-ft grid system created around the building. The samples will be collected from the center of each selected grid square. The grid system will be prepared on a plot plan or similar drawing of the property. If two samples cannot be obtained from each side of the structure, samples will be obtained from the remaining sides to yield a total of eight samples. Before and after samples will be collected from the same approximate locations. The sampling locations will be marked on the site drawing. In addition, a marker (e.g., fluorescent orange painted meter pipe) will driven into the ground to mark the location of the soil sample collected before demolition of the structure. QAPP Section B August 17, 2000 Revision 1 Page 7 of 28 B.1.5 Moisture Content of ACM To determine the effectiveness of the water application process on wetting the asbestos- containing materials in the structure, 10 representative bulk samples of the asbestos-containing materials will be collected. The ten bulk samples will be collected of the asbestos-containing materials after the structure has been demolished. The water (moisture) content of each sample will be determined. A water meter (or an equivalent device) will be installed at the hydrant to measure the volume of water used during demolition of the structure. B.1.6 Water Used for Wetting Structure/Debris The water used to wet the structure and resultant demolition debris will be sampled to determine the asbestos content. That is, each sample will be analyzed for asbestos fibers greater than 0.5 /�m in length; the AHERA (40 CFR 763) definition. B2 SAMPLING METHODS REQUIREMENTS B.2.1 Air Sampling QAPP Section B August 17, 2000 Revision 1 Page 8 of 28 The samples will be collected on open-face, 25-mm-diameter 0.45-,um pore size mixed cellulose ester (MCE) filters with a 5-µm pore size MCE diffusing filter and cellulose support pad contained in a three-piece cassette with a 50-mm non-conductive cowl. This design of cassette has a longer cowl than the design specified in ISO 10312:1995, but it has been in general use for some years for ambient and indoor air sampling. Disposable filter cassettes with shorter conductive cowls, loaded with the appropriate combination of filter media of known and consistent origin, do not appear to be generally available. The filter cassettes will be positioned on tripods approximately 5 feet above the ground or at the elevation best suited to achieve an unobstructed representative air sample. The filter assembly will be attached with fle�ble Tygon� tubing (or an equivalent material) to an electric-powered (110 VAC) 1/6-horsepower vacuum pump operating at an airflow rate of appro�mately 6.3 liters per minute to achieve the target air volume of 3,000 liters over an eight hours. Each pump will be equipped with a flow control regulator to maintain the initial flow rate of within +/- 10% throughout the sampling period. Although the pilot test described in Section B.1.3 will determine the optimal target air volume, it is anticipated that the air volume for each sample will be appro�mately 3,000 liters. If 110 VAC line power is not available, portable gasoline-powered generators will be used to power the sampling pumps. B.2.2 Meteorological Monitoring Meteorological data will be collected to support the determination of valid sampling . periods. Data validity will be based primarily on wind directions which lend themselves to maintaining the monitors in an upwind and downwind orientation from the demolition site or landfill. A combination of nearby National Weather Service (NWS) 12-hour wind direction forecasts, on-site meteorological data collection using continuous monitoring, and individual monitoring site qualitative collection data will be used to determine several monitoring objectives. QApP Section B August 17, 2000 Revision 1 Page 9 of 28 These objectives include the following: l. Forecasting a valid upcoming sampling day. 2. Providing ongoing data collection to support final data validation. 3. Checking ongoing data throughout a sampling period overall and at specific sampling locations. The primary specification for objectively deternuning monitored data validity and the determination of go/no-go on each sample day will be based on two meteorological conditions. The first is rainfall. If the NWS forecasts greater than a trace (0.1 inch) amount of rainfall for the upcoming 24-hour sampling period, the sampling day will be canceled. The second criterion for evaluating data validity and go/no-go situations will be wind direction. For June all winds coming from the 135 ° through 202.5 ° wind sectors (southeast through south through southwest) will be selected as valid wind flows. Wind directions prior to each sampling day will be estimated through NWS forecasts. Sampling will proceed whenever winds are generally forecast for the southwest through northeast (clockwise through northwest). Prior to the start of each day's field activities, the NWS at the Dallas-Fort Worth Inte�national Airport will be contacted to obtain 12-24 hour wind direction and precipitation forecasts. If the conditions are acceptable, the sampling day will proceed. For ongoing field activities after the decision has been made to proceed, both continuously recorded wind speed and direction will be collected as well as predetermined time spot checks at each monitoring site. A meteorological station will be installed at both the demolition site and landfill. Each station will consist of a Met One Instruments, Inc. Automet meteorological data system. It will include continuous wind speed and direction sampling and data logging over the duration of the sampling period. All data will be collected and archived in the data logger which can be checked on a routine basis with direct readout as well as downloading to a personal computer whereby related software will be used to assess hourly, daily, and period archived data. The wind station will be tripod mounted in an appropriate location away from all obstructions. The Automet sensors and their associated sensitivity are approved for use in Prevention of Significant Deterioration Monitoring Projects under U.S. EPA and will provide significant detail to the wind direction tabulations. QAPP Section B August 17, 2000 Revision 1 Page 10 of 28 The meteorological station operator will also collect wind speed data using a hand-held Dwyer wind speed meter and wind direction data using a dark-colored ribbon attached to the top of a 6-foot wooden stick. Readings will be taken once every 30 minutes over a duration of about 1 minute using the 1-minute averages to represent the period. A logbook will be kept which notes these wind directions and wind speeds as well as those noted on the Automet system data logger for the same time period. The manual measurement (wind speed and wind direction) ma.de at meteorological station will also be ma.de at one other upwind and two downwind sampling locations. They will also be at the same specified 1 minute of each 30-minute time period during sample collection. The wind speed and wind direction will be noted in a logbook at each sampling location. Consistency between observations will be promoted through the use of identical hand-held instruments as well as previous training on proper observation techniques by each site attendant. If during sampling the wind directions fall outside of the acceptable range at the main meteorological station for 30 or more concurrent minutes, sampling activities will cease for the day. The samples will be archived or voided. B.2.3 Soil Sampling The soil samples will be collected using a clean metal scooping tool (e.g., a garden trowel). The samples will be collected from the center of the grid square (see Section B.1.4). To the extent feasible, each sample will represent the top 1 to 1'h inches of soil from a 4 inch by 4 inch area. The area will be delineated using a metal template with a 1'fi inch vertical flange of sufficient strength to allow the flange to be pushed into the soil. The template will be constructed of galvanized sheet metal. B.2.4 Water Sampling One water sample will be collected from each water source (i.e., water hydrant) that will be used to wet the structure and resultant demolition debris. The sample container will be an unused, precleaned, screw-capped bottle of glass or low density (conventional) polyethylene and capable of holding at least 1 liter. (Ideally, water samples are best collected in glass bottles.) Prior to collecting the sample, allow the water from the water source to run to waste for a Q�P Section B August 17, 2000 Revision 1 Page 11 of 28 sufficiently long period to ensure that the sample collected is representative of fresh water. As an additional precaution against contamination, each bottle should be rinsed several times in the source water being sampled. Two separate samples of approximately 800 milliliters each will be collected. An air space will be left in the bottle to allow efficient redispersal of settled material before analysis. The second bottle will be stored for analysis if confirmation of the results obtained from the analysis of the first bottle is required. The samples will be transported to the analytical laboratory and filtered by the laboratory within 48 hours of each sample collection. No preservatives or acids will be added. At all times after collection, the samples will be stored in the dark and refrigerated at about 5° C(41 ° F) in order to minimi�.e bacterial and algal growth. The samples will not be allowed to freeze, since the effects on asbestos fiber dispersions are not known. QAPP Section B August 17, 2000 Revision 1 Page 12 of 28 B3 SAMPLE CUSTODY REQUIREMENTS Chain-of-custody procedures emphasize careful documentation of constant secure custody of samples during field, transport, and analytical stages of environmental measurement projects. The sample custodian responsible for the proper chain-of-custody during this project is: Tracy Bramlett, CIH, CSP Industrial Hygiene & Safety Technology, Inc. 2235 Keller Way Carrollton, Texas 75006 Phone: 972.478.7415; fax: 972.478.7615 B.3.1 Field Chain-of -Custody Each sample will have a unique project identification number. This identification number will be recorded on a Sampling Data Form (Figure A-3) along with the other information specified on the form. After the labeled sample cassettes are recovered from the sampling trains, the sample custodian will complete an Analytical Request and Cha.in-of-C�istody Form (Figure B- 2). This form will accompany the samples, and each person having custody of the samples will note receipt of the same and complete an appropriate section of the form. Samples will be sent to Laboratory (To Be Determined) via Federal Express Standard Overnight Service. B3.2 Microscopy Laboratory The laboratory's sample clerk will examine the shipping container and each filter cassette to verify sample numbers and check for any evidence of damage or tampering, note any changes or indication of tampering on the accompanying chain-of-custody form, and then forward the form to Tracy Bramlett. The sample clerk will log in all samples and assign a unique sample identification number to each sample and sample set. r-i 0 e--I � Q O z � a� E � I U O � U O C � T � � � d 0 0 � zo ,Q U � � � � W O � � N= U � � � Qz Q � _ U O � 0 a a� � � o Z Z m — c a � � � o m O � � � ` c�v U ca °� J � � ro � a U .n m J a� � � � c�n � Z � N J Z aUi v � E O d U ro d o o F- °- a °' E m � 11.� z J � tJ1 0. � W Z ha- Z � U ll.� Z O Q�p Section B August 17, 2000 Revision 1 Page 13 of 28 �a O J Q � � a o c c°�i E O d U OC U� Q� N� N� �s, � � o i- o i- �� � aro m �a a�i o � O' � c�a � � J T � ici 0 > N d � a`Z d y _ ❑ � � � a Q � � o � o O. � � C� d�+ , N m 0 � � � � c°�i a o � �> E � � � c � c ro m � m m � � m r � �j N E L � � •.�. G � � T d c� � O Q U � E � t�i � a a� � V 0 � � � � � i= O {_ ❑ c � :° .n d �� � T — m c ._ p- O � a� � tE0 II. ❑ Y N � � � � N � o � E �' � ' � c E a� N � � ❑ � �� C � L .a .L] � '� � a v �o 2 N� f" � = o L o al � N ro v 'O �_=° 7��° iii E E C N N �� C� C� � � a � � � . . � f0 � L d � N � � z �� '� � c E �� cc � E a o o � o � m o cn a z h- z r� �,i N c� B4 ANALYTICAL METHOD REQUIIZEMENT5 B.4.1 Air Samples QAPP Section B August 17, 2000 Revision 1 Page 14 of 28 The 0.45-�cm pore size m�ed-cellulose ester (MCE) filters will be prepared and analyzed using International Organization of Standardization (ISO) Method 10312:1995 (15L Ed.), "Ambient Air - Determination of Asbestos Fibres - Direct-Transfer Transmission Electron Microscopy Method." A copy of the method is contained in Appendix B. The principal objective of these analyses is to provide air concentration data of sufficient quality to support the development of conclusions regarding the effective of the Fort Wor•th Method to control the release of asbestos fibers during the demolition of substandard structures containing RACM B.4.1.1 TEM Specimens Preparation TEM specimens shall be prepared from the ambient air filters using the dimethylformamide (DMF) collapsing procedure of ISO 10312:1995, as specified for cellulose ester filters. DMF shall be used as the solvent for dissolution of the filter in the 7affe washer. For each filter, a minimum of four TEM specimen grids shall be prepared from a one quarter sector of the filter, using 200 mesh indexed copper grids. The remaining part of the filter shall be archived until further notice, in the ,original cassette in clean and legally secure storage, to be possibly selected for quality assurance analyses. B.4.1.2 Measurement Strategy The minimum aspect ratio for the analyses shall be 3:1, as permitted by ISO 10312:1995. 2. The analyses shall be performed by a two-stage examination of the TEM specimens, as indicated in ISO 10312:1995, in order to provide data of sufficient precision for each of the structure size ranges of interest. The size ranges of structures that shall be evaluated, and target analytical sensitivities, for the anticipated collected air volume of 3000 liters, will be as shown in Table B-2. QAPP Section B August 17, 2000 Revision 1 Page 15 of 28 Table B-2. Appro�mate Number of Grid Openings to Achieve Target Analytical Sensitivity Based on Air Volume of 3000 Liters (Direct-Transfer Preparation of TEM 5pecimens) Appro�mate Number of Target Appro�mate Appro�mate 0.01 mm2 Analytical Magnification Area Grid Sensitivity for Examined Openings Size Range s/cc Examination mm2 Required All Structures (Minimum Length of 0.0005 20000 0.256 26 0.5 pm) Longer than 5 pm, 0.0001 10000 0.256 26 (All Widths) 3. The stopping point in the analysis for each of the examinations defined in 2 shall be 100 primary asbestos structures, or after the completion of the examination of the grid opening during which the target analytical sensitivity is achieved. A minimum of 4 grid openings shall be examined, in accordance with the specifications of ISO 10312:1995. 4. The structure counting data shall be distributed approximately equally among a minimum of 3 specimen grids, prepared from different parts of the filter sector. 5. The TEM specimen examinations at approximately 20,000 and 10,000 shall be performed as independent measurements. 6. Measurement of fiber dimensions is extremely important for accurate determination of aspect ratios. Lengths and widths of fibers shall be recorded in millimeters as measured on the fluorescent screen. Where the observed width of a fiber is lower than approximately 5 mm on the screen at either of the two magnifications used for the 'TEM specimen examinations, the measurement errors may seriously compromise the accuracy of the calculated aspect ratio. Accordingly, in this situation, the magnification shall be increased by a factor of approximately five times to obtain an accurate measurement of the width. For example, the width of a 1 mm wide fiber cannot be accurately estimated on the screen. A five-fold increase in the magnification increases the dimension to 5 mm, which can be estimated with sufficient accuracy for the purpose of this project. Q�p Section B August 17, 2000 Revision 1 Page 16 of 28 B.4.2 Soil Samples The asbestos content of the soil will be determined using a method developed by U.S. EPA, Region I: Standard Oper•ating Procedur•e for the Screening Analysis of Soil and Sediment Samples for Asbestos Content (SOP:EIA-INGABED2-SOP, January 11, 1999). To more accurately quantify the amount of asbestos in the soil samples, the samples will be prepared using the procedure specified in the addendum to the method. A copy of the method is contained in Appendix C. B.4.3 Moisture Content of ACM The water (moisture) content of the bulk samples of asbestos-containing materials (ACM) will be determined in accordance with ASTM Standard Test Method D 4959-00 "Determination of Water (Moisture) Content of Soil by Direct Heating." The method will be modified (as necessary) to accommodate the ACM bulk samples. A copy of the method is contained in Append� D. B.4.4 Water Samples The asbestos content of the water used to wet the structure and resultant demolition debris will be determined using EPA Method 100.1 "Analytical Method Determination of Asbestos in Water." A copy of the method is contained in Appendix E. Measurement of fiber dimensions is important. Dimension of fibers is recorded as length and width if greater than 0.5 ,um in length. Reference EPA Method 100.1 for counting and sizing rules for bundles, fiber aggregates, etc. The analysis may be stopped after 100 fibers have been counted or 20 grid openings have been examined. The sample grid will be examined in a transmissions electron microscope (TEM) at a magnification of about 20,000. QAPP Section B August 17, 2000 Revision 1 Page 17 of 28 B5 QUALITY CONTROL REQUIREMENTS The overall quality assurance objective is to provide defensible data of known quality meeting quality assurance objectives. To that end, procedures are developed and implemented for field sampling, chain-of-custody, laboratory analysis, reporting, and audits that will provide results which are scientifically valid and legally defensible in a court of law. B.5.1 Field Quality Control Checks Quality control checks for the field sampling aspects of this project will include, but not be limited to, the following: • Use of standardized forms (e.g., Figures A-3, A-4, B-2) to ensure completeness, traceability, and comparability of the data and samples collected. • Calibration of air sampling equipment including pre- and post-sample calibrations using a calibrated precision rotameter. • Proper handling of air sampling filters to prevent cross contamination. • Collection of field blanks; see Section B.5.2.2. • Field cross checking of data forms to ensure accuracy and completeness. B.5.2 Analytical Quality Control Checks B.5.2.1 Quality Control Check of Filter Media Before air samples are collected, a minimum of 2 percent of unused filters from each filter lot of 100 filters will be analyzed to determine the mean asbestos structure count. If the mean count for all types of asbestos structures is found to be more than 10 structures/mm2, or if the mean fiber count for asbestos fibers and bundles longer than or shorter than 5�cm is more than 0.1 fiber/mm2, the filter lot will be rejected. By comparison, this criterion is more restrictive than that specified by EPA in AHERA (i.e., 18 structures/mm2 of filter area). QAPP Section B August 17, 2000 Revision 1 Page 18 of 28 B.5.2.2 Blank Contamination To ensure that contamination by extraneous silicate mineral fibers during sample collection and specimen preparation is insignificant (see criteria in Section B.5.2.1) compared with the results reported on samples, a continuous program of blank measurements will be established. This will include filter lot blanks (see Section B.5.2.1), field blanks (open and closed), laboratory blanks, and laboratory clean area blanks. Field Blanks -- Closed field blanks are filter cassettes that have been transported to the sampling site and sent to the laboratory without being opened. Open field blanks are filter cassettes, that have been transported to the sampling site, opened for a short time (< 30 seconds) without any air having passed through the filter, and then sent to the laboratory. The number of open and closed blanks that will be collected and analyzed is presented in Table B-1. Laboratory Blanks -- Laboratory blanks are unused filters (or other sample device or container) that are prepared and analyzed in the same manner as the field samples to verify that reagents, tools, and equipment are free of the subject analyte and that contamination has not occurred during the analysis process. The laboratory will analyze at least one blank for every ten samples or one blank per prep series. Blanks are prepared and analyzed along with the other samples. If the blank control criteria (Section B.5.2.1) are not met, the results for the samples prepared with the contaminated blank are suspect and should not be reported (or reported and flagged accordingly). The preparatian and analyses of samples should be stopped until the source of contatnination is found and eliminated. Before sample analysis is resumed, contamination-free conditions shall be demonstrated by preparing and analyzing two blanks that meet the blank control criteria. Laboratory blank results shall be documented in the quality control log. Laboratory blank count sheets should be maintained in the project folder along with the sample results. Laboratory Clean Area Blanks -- Clean area blanks are prepared whenever contamination of a single laboratory prep blank exceeds the criteria specified in Section B.5.2.1 or whenever cleaning or servicing of equipment has occurred. To check the clean area, an used filter is left open on a bench top in the clean area for the duration of the sample prep process. The blank is then prepared and analyzed using ISO Method 10312:1995. If the blank control criteria (see Section B.5.2.1) are not met, the area is cleaned using a combination of HEPA-filter vacuuming Q�P Section B August 17, 2000 Revision 1 Page 19 of 28 and a thorough wet-wiping of all surfaces with amended water. In addition, air samples should be taken in the sample prep room to verify clean air conditions. At least 2,500 liters of air should be drawn through a 25-mm-diameter 0.45-,um pore size MCE filter using a calibrated air sampling pump. The samples should then be analyzed using ISO Method 10312:1995. If blank control criteria are not met, sample preparation shall stop until the source of contamination is found and eliminated. Clean area sample results shall be documented in the Clean Area Blank Log. B.5.3 Analytical Precision and Accuracy Quality control checks will be performed on a routine basis to verify that the analysis system is in control. Most laboratory Quality Control Programs include frequent quality tests for both accuracy and precision. Because of the difficulty of preparing quantitative asbestos standard materials, neither spiked samples nor known quantitative samples can be used on a routine basis for asbestos analysis accuracy testing. Therefore, routine quality control testing for asbestos focuses on precision checks, which involve a second count or multiple counts of a sample or a portion of a sample. B.5.3.1 Replicate Analysis The precision of the analysis is determined by an evaluation of repeated analyses of randomly selected samples. A replicate analysis will be performed on 5% of the samples analyzed to assess the precision of the counting abilities of the individual analysts. A replicate analysis is a second analysis of the same preparation, but not necessarily the same grid openings, performed by the same microscopist as in the original analysis. The conformance expectation for the replicate analysis is that the count from the original analysis and the replicate analysis will fall within a 95% confidence interval for the average count, or as follows: LCL < A1 AZ < UCL where: A1 is the original count, AZ is the replicate count, LCL is the lower confidence limit, UCL is the upper confidence limit. QAPP Section B August 17, 2000 Revision 1 Page 20 of 28 Should either the original or replicate count fall outside the acceptance range, the grid is re- examined to determine the cause of the count variation. The 95% confidence interval is based on the Poisson distribution. For average counts less than or equal to 20 structures, Table F-1 in ISO Method 10312:1995 (see Appendix C) should be used to derive the upper and lower 95% confidence limits. For average counts greater than 470 structures, a normal approximation can be used. The upper and lower confidence limits based on the normal approxima.tion are calculated as follows: where: LCL = ,u - 1.96 x ✓�.c UCL = �c + 1.96 x ✓�c ,u is the average count, ✓µ is the definition of the Poisson standard deviation. B.5.3.2 Duplicate Analysis A duplicate sample analysis is also performed on 5% of the samples analyzed to assess the reproducibility of the analysis and quantify the analytical variability due to the filter preparation procedure. A duplicate analysis is the analysis of a second TEM grid preparation prepared from a , different area of the sample filter performed by the same microscopist as the original analysis. _ The conformance expectation is similar to that for replicate analyses with one exception. That is, the count from the original analysis and the duplicate analysis should fall within a 95% confidence interval for the average count. Q�P section B August 17, 2000 Revision 1 Page 21 of 28 B.5.4 Veri�cation Counting Due to the subjective component in the structure counting procedure, it is necessary that recounts of some specimens be made by a different microscopist (i.e., a microscopist different than the one that performed the original analysis) in order to minimi�.e the subjective effects. Verification counting will involve re-examination of the same grid opening by a different microscopist. Such recounts provide a means of maintaining comparability between counts made by different microscopists. These quality assurance measurements will constitute approximately 10 percent of the analyses. Repeat results should not differ at the 5% significance level. QAPP Section B August 17, 2000 Revision 1 Page 22 of 28 B6 INSTRUMENT/EQUIPMENT TESTING, INSPECTION, AND MAINTENANCE REQUIREMENTS B.6.1 Field Instrumentation/Equipment Field equipment/instruments (e.g., sampling pumps, meteorological instrumentation) will be checked and calibrated before they are shipped or carried to the field. The equipment and instruments will be checked and calibrated at least daily in the field before and after use. Spare equipment, such as air sampling pumps, precision rotameters, and flow control valves will be kept on-site to minimize sampling downtime. Backup instruments (e.g., meteorological instrumentation) will be available within one day of shipment from a supplier. B.6.2 Laboratory Equipment/Instrumentation As part of the (To Be Determined) Laboratory's QA/QC Program, a routine preventive maintenance program is performed to minimize the occurrence of instrument failure and other system malfunctions of their transmission and scanning electron microscopes. The laboratory has an internal group and equipment manufacturer's service contract to perform routine scheduled maintenance, and to repair or to coordinate with the vendor for the repair of the electron microscope and related instruments. All laboratory instruments are maintained in accordance with manufacturer's specifications and the requirements of ISO Method 10312:1995. � QAPP Section B August 17, 2000 Revision 1 Page 23 of 28 B7 INSTRUMENT CALIBRATION AND FREQUENCY B.7.1 Field Instrument/Equipment Calibration B.7.1.1 Air Sampling Pumps The air sampling pumps with a flow control valve will be evaluated to ensure that they are capable of maintaining a stable flow rate for a given static pressure drop; i.e., the pumps can maintain an initial volume flow rate of within +/- 10% throughout the sampling period. Prior to use the sampling pumps will be tested against the pressure drop created by a 25-mm-diameter, 0.45-,um pore size MCE filter with a 5-�cm pore size 1VICE backup diffusing filter and cellulose support pad contained in a three-piece cassette with 50-mm cowl at a flow rate of approximately 6 liters per minute at STP. B7.1.2 Airflow Calibration Procedure A flow control valve will be used to regulate the flow rate through the sampling train during sampling. The airflow rate will be determined both before, at the mid-point, and after sampling using a calibrated precision rotameter (Manostat Mode136-546-215). The precision rotameter (a secondary calibration standard) will be calibrated using a primary standard airflow calibrator (Gilabrator electronic flow meter). A detailed written record will be maintained of all calibrations. It will include all relevant calibration data, including the following elements: • Gilabrator model and serial number • Rotameter model and serial number • Sampling train (pump, flow control valve, and filter) • X- and Y- coordinate calibration data , � • Intercept, slope, and correlation coefficient from a linear regression analysis of the calibration data, and resulting linear regression equation that will be used to determine the sampling flow rate • Relevant calculations • Dry bulb temperature and barometric pressure : • Name of person/affiliation that performed the calibration and linear regression analysis QAPP Section B August 17, 2000 Revision 1 Page 24 of 28 B.7.2 Calibration of TEM The TEM shall be aligned according to the specifications of the manufacturer. The TEM screen magnification, electron dif&action (ED) camera constant, and energy dispersive X-ray analysis (EDXA) system shall be calibrated in accordance with the specifications in ISO Method 10312:1995, Annex B(see Appendix B). QAPP Section B August 17, 2000 Revision 1 Page 25 of 28 BS INSPECTION/ACCEPTANCE REQUIREMENTS FOR SUPPLIES AND CONSUMABLES B.8.1 Air Sampling Filter Media Please see Section B.5.2.1 regarding the quality control check of the filter media. Q�p Section B August 17, 2000 Revision 1 Page 26 of 28 B9 DATA ACQUI5ITION REQUIREMENTS (NON-DIIZECT MEASUREMENTS) B.9.1 Precision The performa.nce goals stated in Section A.7 "Quality Objectives and Criteria for Measurement Data" assume a between-sample variability of 250% or less. The actual between- sample component of variability will be established from the data using standard variance component analyses. If the target precision is not achieved, the false-negative error rate will be greater than the target rate of 5% and failure to obtain a statistically significant result will not provide strong evidence against the null hypothesis being tested. If a statistically significant result is obtained, the false-negative error rate is of little concern, since it is clear that a false negative error has not occurred. Laboratory precision (coefficient of variation), which is a component of between-sample variability, will be estimated from duplicate analyses of a subset of samples. This will provide a measure of the relative contribution of laboratory analysis to the total between-sample variability. This information will be useful for performing statistical power calculations for follow-up air monitoring surveys. B.9.2 Completeness � An overall measure of completeness will be given by the percentage of samples specified in the study design that yield usable data. The quality control criterion is > 95%. B.9.3 Accuracy Duplicate counts of a subset of randomly selected samples will be performed by having the same microscopist count two sets of grids prepared from the same sample. The results of the counts will be compared, and those which do not fall within the 95% confidence limits for a Poisson variable will be subjected to a further recount and/or a count of a third preparation in an attempt to resolve the discrepancy. A count by a second microscopist may also be employed. In addition, it is expected that a subset of samples will be selected at random by the City of Fort Worth's Quality Assurance Manager to be analyzed by an outside "second" laboratory. QAPP Section B August 17, 2000 Revision 1 Page 27 of 28 B10 DATA MANAGEMENT Commercially available computer hardware and software used to manage measurement data is controlled to ensure the validity of the data generated. Controls include system testing to ensure that no computational errors are generated and evaluation of any proposed changes to the system before they are implemented. Commercially available software does not require testing, but validation of representative calculations are required using alternative means of calculations. B.10.1 Data Assessment Sample data will be reviewed by the laboratory during the reduction, verification, and reporting process. During data reduction, all data will be reviewed for correctness by the microscopist. A second data reviewer will�also verify conectness of the data. Finally, the Laboratory Director (To Be Determined) will provide one additional data review to verify completeness and compliance with the project QAPP. The City of Fort Worth's Quality Assurance Manager, will also select a random sample of the data for the same purpose. Any deficiencies in the data will be documented and identified in the data report. B.10.2 Data Management Field and laboratory data will be entered into a Microsoft Excel spreadsheet to facilitate organization, manipulation, and access to the data. Field data will include information such as sampling date, sample number, sampling site, sample description and location, sample type, air volume, and sampling period. Laboratory data will include information such as sample number, sample date received and analyzed, type of analysis, magnification, grid location, grid square area, filter type, number of grids examined, number of asbestiform structures counted, structure type (fiber, bundle, cluster, or matrix), and structure length and width. An example format for reporting the structure counting data is contained in Figure 7 of ISO Method 10312:1995 (see Appendix B). QAPP Section B August 17, 2000 Revision 1 Page 28 of 28 B.10.3 Statistical Analysis The data collected during the building demolitions and at the landfill will be analyzed using standard analysis of variance (ANOVA) techniques. The ANOVA is a formal statistical procedure that tests whether two or more groups of data are significantly different, on average. The natural logarithm of each sample concentration will be used in the comparisons. Log- transforma.tion is used to make the variances more equal and to provide data that are better approximated by a norma.l distribution. The use of a log-transforma.tion is equivalent to assuming the data follow a log-normal distribution; the log-normal distribution is commonly assumed for asbestos measurements and other environmental contaminants. Sample results reported as non- detected will be replaced by the analytical sensitivity divided by two to calculate summary statistics and to perform all statistical analyses. All statistical comparisons will be made at the O.OS level of signi.ficance. QAPP Section C August 1'7, 2000 Revision 1 Page 1 of 4 C ASSESSMENT/OVER5IGHT C1 ASSESSMENT AND RESPONSE ACTIONS C.l.l Performance and System Audits C.1.1.1 Field Audits The City of Fort Worth staff will be present during the study. The City's Technical Project Officer will conduct periodic field audits. The audit will include, but not limited to the examination of sample collection and equipment calibration procedures, sampling data and chain- of-custody forms, and other sample collection and handling requirements specified in the QAPP. The auditor will document any deviations from the QAPP so that they can be corrected in a timely manner. The auditor will independently measure the flow rate of at least 50% of the air samplers in operation at the time of the audit. The relative accuracy (A%) of the audited flow rates will be established as follows: A% = 100% - RE% where RE%, the relative error, is calculated as: where: RE% _ (F-A) / A x 100 F= flow rate measured by the field crew A= flow rate measured by the auditor. The performance objective for the relative accuracy will be set between 90% and 110%. Prior to leaving the site, the auditor will debrief Tracy Bramlett regarding the results of the audit and any recommendations, if necessary. The results of the audit will be presented in a written report prepared by the auditor. QAPP Section C June 2, 2000 Revision 0 Page 2 of 4 C.1.1.2 Laboratory Audit Ms. Hoover (Quality Assurance Manager) or an independent laboratory quality assurance " consultant selected by Ms. Hoover will conduct at least one quality assurance audit of the Laboratory (To Be Determined). The first audit will be conducted at the onset of the project to . verify that all procedures specified in the QAPP are understood and are being followed. C.1.2 Corrective Actions Sampling and analytical problems may occur during sample collection, sample handling and documentation, sample preparation, laboratory analysis, and data entry and review. Immediate on-the-spot corrective actions will be implemented whenever possible and will be documented in the project record. Implementation of the corrective action will be confirmed in writing by completing a Corrective Action Report (Figure C-1). QAPP Section C June 2, 2000 Revision 0 Page 3 of 4 Originator: Date: Project Name/Number: Corrective Action Number: Description of Problem State Cause of Problem (Give Date and Time Identified) State Conective Action Planned QA Officer Comments: (Include Persons Involved in Action) Signatures Project Manager Comments: QA Officer Project Manager Originator Figure C-1. Corrective Action Report. Q�P Section C June 2, 2000 Revision 0 Fage 4 of 4 C2 REPORTS TO MANAGEMENT Effective communication is an integral part of a quality system. Planned reports provide a structure to inform management of the project schedule, deviations from the approved QAPP, impact of the deviations, and potential uncertainties in decisions based on the data. The IHST Project Manager (Tracy Bramlett) will provide verbal progress reports to the City of Fort Worth's Project Manager (Kathryn Hansen). These reports will include pertinent informa.tion from the data processing and report writing progress reports and corrective action reports, as well as the status of analytical data as determined from conversations with the laboratory. Mr. Bramlett will promptly advise Ms. Hansen on any items that may need corrective action. A written report will be prepared for each field and laboratory audit. These reports will be submitted to the City of Fort Worth's Project Manager. QAPP Section D June 2, 2000 Revision 0 Page 1 of 3 D DATA VALIDATION AND USABILITY Dl DATA REVIEW, VALIDATION, AND VERIFICATION REQUIREMENTS The data will be reviewed and validated by the City of Fort Worth's Quality Assurance Manager or by an independent quality assurance consultant (To Be Determined) selected by the City of Fort Worth. QAPP Section D June 2, 2000 Revision 0 Page 2 of 3 D2 VALIDATION AND VERIFICATION METHODS The analytical laboratory will perform in-house analytical data reduction and verification under the direction of the laboratory's quality assurance manager. The laboratory's quality assurance manager is responsible for assessing data quality and advising of any data rated as "unacceptable" or other notations which would caution the data user of possible unreliability. The City of Fort Worth's quality assurance manager or an independent quality assurance consultant (To Be Determined) will conduct a systematic review of the data to verify compliance with the established quality criteria in the QAPP and ISO Method 10312:1995. The data review will identify any out-of-control data points and data omissions. Based on the extent of the deficiency and its importance in the overall data set, the laboratory ma.y be required to re-analyze the sample. Included in the data validation of a sample set will be an assessment of chain-of- custody and analyses of field quality control samples (open and closed field blanks). The precision of the data will be determined by calculating the coefficient of variation for the replicate and duplicate sample analyses as well as the analyses of the field duplicate samples. QAPP Section D June 2, 2000 Revision 0 Page 3 of 3 D3 RECONCILIATION WITH DATA QUALITY OBJECTIVES The proposed statistical methods to analyze the data and determine the significance of departures (positive and negative) from the assumptions established in the Data Quality Objectives are presented in Section B.10. QAPP Section E June 2, 2000 Revision 0 Page 1 of 1 E1 REFERENCES 1. U.S. Environmental Protection Agency. EPA Guidance for Quality Assurance Project Plans — EPA QA/G-5. EPA/600/R-98/018, February 1998. 2. City of Fort Worth, Texas, Project XL Proposal "Asbestos Management in the Demolition of Substandar•d Structures as a Nuisance Abatement,"(September 30, 1999). Prepared by Department of Environmental Management, City of Fort Worth, Texas 76102. 3. U.S. Environmental Protection Agency. Ambient Airborne Asbestos Levels in Alviso, California. Prepared by John R. Kominsky and Ronald W. Freyberg. Contract No. 68- CO-0048, Apri127, 1995. 4. U.S. Environmental Protection Agency. Ambient Air Monitoring at the Moss Landing Harbor District: Moss Landing, California. Prepared by John R. Kominsky and Ronald W. Freyberg. EPA Contract No. 68-D2-0058, October 17, 1990. 5. Kominsky, J.R., R.W. Freyberg, J.A. Brownlee, D.R. Greber. AHERA Clearance at Twenty Abatement Sites. EPA/600/52-91/028, August 1991. 6. Berman, D.W. and Chatfield, E.7. (1990). Superfund Method for the Determination of Asbestos in Ambient Air. Part 2: Technical Background Document. Prepared for the Environmental Services Branch of the U.S. Environmental Protection Agency. Washington, D.C. EPA/540/2-90/OOSb. Q�p Appendix A June 2, 2000 Revision 0 Appendix A Comparison of the Asbestos NESHAP and the Fort Worth Method for the Demolition of Substandard Structures Table - 1 Comparison of the Asbestos NESHAP and the Fort Worth Method for Demolition of Substandard Structures ,. .. �. o- � o� � .. .. ;o . � � ��� � � ., � �. , �• � '• A Unifni 5tates 11 Unite,i Siares ��� ��� Agenc/m?ntai Pr,�lxti�n ��', E PA E�encnmental Pratacticn � FOI�'T�OI�THv. �9 1 ASBESTOS ASSESSMENT Not required. Full AHERA Level Asbestos Full AHERA Level ,4sbeslos Assessment Assessmenl. DEMOLITION NOTIFICATION Written noti(Cation as early a5 pOSsible Writteft notifCation at least ten woriCing 4Vritlen nolificahon a[ least TWO svorkiny before, but no[ later Ihan the follo�ving days before work begins. deys before wcrk beyins. � working day. REMOVAL OF RACM PRIOR TO RP,CM not removed prior to demolition. Remove RACM under (ull containment if Rt\CM not remnveci pnor fo demoli�ian. DEMOLITION Ihefe I5: Note' SPRAY-ON FIREPROOFING 1. At Ieast 80 linear meters (260 li�ear AND LARGE QUANTITIES OF feel) on pipes or at Ieast 15 square THERNIAL SYSTEM meters (160 square feet) on other INSULATION WILL BE facility wmponents; or ADDRESSED UNDER fl1LL 2. At Ieast 1 cubic meter (35 cubic (eet) CONTAiNMENT CONDITIONS. off facility componenls where the length o� area could not be . measured previously. Adequateiy wet asbeslos-containing waste material. Afler wetting, sea� in leak-tighl containers while wel. If matenals will not fit into containers wilhou! additional breakage, put materials in Ieak-tight wrapping. Label con[ainers or wrapped materials using OSHA compliant waming labels. EMISSIONS CONTROLS DL/RING �ischarge no Visible Emissions from Discharge no Visible Emissions from Discharye no Visible Emissions from DEMOUTION R.4Cti1 or asbes[os-containing waste RACM w asbestos-coritaining waste R�CM or as-bestos-containing waste matenaL , material. material. HANDLING PROCEDURES FOR Adequately wet Ihe pertion of the faci�ity Adequately wet asbestos-containing Adeyuately wet THE FACILITY during OEMOLITION ASBESTOS- Ihat Confains RACtiI dUling Ihe W�eCking waste matenai at all times aker the WfeChing Ope�atiUn CONTAINING WASTE MATERIAL operation. demolition and keep wet during handling � and loading for transport to a disposai Adequateiy �,vet DE�IOLITiON DEBRIS � Adequately wet as6estos-mntaining site. at all hmes aker demolition and keep waste material at all [imes aker � wet duriny handling and loadiny for demolition and keep wet dunng handling Asbestos-containing waste materials Iransport to a disFosal site. and loading for transport to a disposai demolished in place do not have to be site. seaied in leak-tight containers or WASTE MATERIALS TO BE wrapping, but may be transported and DISPOSED IN BULK WITHIN Asbes�os-containing �,vaste materials do disposed of in buik. TRAILERS COVERED WITH TARPS. not have to be sealed in leak-tight containers or wrapping, bul may be Note: Does not apply to Category I Non- transported and disposed of in bulk. Friabfe ACM waste and Calegory II Non•Friable ACM waste that did not become crumbled, puiverized, or reduced to powder. TRANSPORTATION OF Mark vehicles used to ifansport Maf1( vehicles us2d to tfansPOft N1ark vehlcles usc9 to transport �EMOLITION ASBESTOS- asbestos-containfny �,vaste material asbestos-containing waste mat2rial as6estos�containing wasle m2tenal CONTAINING WASTE MATERIAL dunng ihe loading and unloading of during the loading and unloading of during Ihe loadiny and unloadiny of waste so that signs are visible. waste so that signs are visible. wasle so Ihat signs are visible. Mani(est RACM shipments. Mani(est RACM shipments. �vtanifest RACM shipmenls. �ISPOSAI oF DEMOLITION Deposit all asbestos-containing was�e Oeposil ail asbestos-containing Waste Deposit all asbestos-containiny �riaste ASBESTOS-CONTAiNING material as soon as practical at a Waste material as soon as p�actical at a waste matenal as soon a� praCtical dt a WaSte WASTE MATERIAL disposal site approved for as6estos disposal sile approved (or asbestos disposal site approved for asbestos disposal, unless it is Category I Plen- disposai, unless it is Calegory 1 Non- dis�sal, unless it is Catr�yory 1 Non Friabie ACht that is not RACM. Fnable ACM that is nol RACM. Friable ACNi that is not Ri\CP.t SITE SUPERVISION OURING At least one representahve �rained in the At least one �epresenlalive t�ained in the At leasl one represzNahve frained in the DEMoli7ioN NESHAP shall be present on-site. NESHAP shall be present on-site. NESHAP shall be present on-site. REcoRos � Ntaintain :vaste disposai records for at Maintain wasle disposal records for at Maintam waste di;posai records (or at MAINTENANCE least hvo years. Ieas� two years. least hvo years. STORMWATER MANAGEMENT Not specified Nol speci(ed Comply with Chapter 12.5, Artide �II, � "Storm Water Protection," Code of the City of Fort Worth. Use best management practices to controi runoff as necessary. ou7000a n�rt MONtTOR�NG OSHA monitoring of �iorkers OSHA monitoring of warkers. AREA SAMPLING TO BE PERFORMED AT ALl FOUR CORNERS OF THE JOB SITE. � OSHA monitoriny of svorkers. WETTING PROCEDURES Adequa[ely wet. Adequately weL Utilize fire hose equipped with variable rate noule to allow for "mistin ' Q�P Appendix B June 2, 2000 Revision 0 Appendix B ISO Method 10312:1995 Ambient Air - Determination of Asbestos Fibres -- Direct-Transfer Transmission Electron Microscopy Method INTER�NATIONAL STANDARD. iso 10312 First edition 1995-05-01 Ambient air — Determination of asbestos fibres — Direct-transfer transmission electron microscopy method Air ambiant — Determination des fibres d'amiante — Methode de microscopie elecironique a transmission directe =/�� — -��� _�/= Reference number �SO 10312:1995(El Printed for you by Document Centerinc., 111 Industrial Road Suite 9, Belmont, CA 94002-4044 Phone: 650-591-7600 Fax: 650-591-761' ISO 10312:1995(Ej v \ Contents 1 Scope ........................................... 2 Normative references ................... 3 Definitions .,....., ....................... 4 Principle ................................... 5 Symbois ot units and abbreviations 6 Reagents .................................. 7 Apparatus ................................. 8 Air sampie collection ,,,,,,,,,,,,,,,, 9 Procedure for analysis .............. 10 Performance characteristics ..., 11 Test report ............................... Page .............................................. 1 .............................................. 2 .............................................. 2 .............................................. 3 ...................:...................... 4 ............................................. 5 ............................................. 5 ........................................... 10 ........................................... 11 .......................................... 18 .......................................... 19 Annexes A Determination of operating conditions for plasma asher ...... 22 B Calibration procedures ........................................................... 23 C Structure counting criteria ...................................................... 25 D Fibre identification procedure ................................................ 33 E Determination of the concentrations of asbestos fibres and bundles longer than 5 µm, and PCM equivalent asbestos fibres ....... 42 F Calculation of results ........................:..................................... ,t3 G Strategies for collection of air samples ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, q7 H Methods for removal of gypsum fibres ................................. 4g JBibliography ............................................................................ 49 � ISO 1995 Ali rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electrornc or mechanicai, including photocopying and microfilm, without permission �n wnting from the publisher. International Organization for 5tandardization Case Postale 56 • CH-1211 GenBve 20 • Swrtzeriand Printed in Switzerla�d �l o ISO ISO 10312:1995(E) Foreword ISO (the international Organization for Standardization) is a woridwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates ciosely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Pubiication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Internationai Standard ISO 10312 was prepared by Technical Committee ISO/TC 146, Air qualiry, Subcommittee SC 3, Ambient aimospheres. Annexes A, B, C, D, E and F form an integral part of this International Standard. Annexes G, H and J are for information only. ISO 10312:7995(E) � ISO 4 � tntroduction This International Standard is applicabie to the determination of airborne asbestos in a wide range of ambient air situations, inciuding the interior atmospheres of buildings, and for detailed evaluation of any atmosphere in which asbestos structures are likely to be present. Because the best availabie medical evidence indicates that the numerical fibre concentration and the fibre sizes are the relevant parameters for evaluation of the inhalation hazards, a fibre counting technique is the only logical approach. Most fibres in ambient atmospheres are not asbestos, and therefore there is a requirement for fibres to be identified. Many airborne asbestos fibres in ambient atmospheres have diameters below the resolution limit of the optical microscope. This Internationai Standard is based on transmission electron microscopy, which has adequate resolution to allow detection of small fibres and is currently the only technique capable of unequivocal identification of the majority of individual fibres of asbestos. Asbestos is often found, not as single fibres, but as very complex, aggregated struc- tures which may or may not be also aggregated with other particles. The fibres found suspended in an ambient atmosphere can often be identified unequivocally, if a sufficient measurement effort is expended. However, if each fibre were to be identified in this way, the analysis would become prohibitively expensive. Because of instrumental deficiencies or because of the nature of the particulate, some fibres cannot be positively identified as asbestos, even though the measurements all indicate that they could be asbestos. Subjective factors therefore contribute to this measurement, and consequently a very precise definition of the procedure for identifica- tion and enumeration of asbestos fibres is required. The method specified in this International Standard is designed to provide the best description possible of the nature, numerical concentration, and sizes of asbestos- containing particles found in an air sample. This International Standard is necessarily complex, because the instrumental techniques used are com- plex, and also because a very detailed and logical procedure must be specified to reduce the subjective aspects of the measurement. The method of data recording specified in this International Standard is de- signed to allow re-evaluation of the structure counting data as new med- ical evidence becomes available. All of the feasible specimen preparation techniques result in some modification of the airborne particulate. Even the collection of particles from a three-dimensional airborne dispersion onto a two-dimensional filter surface can be considered a modification of the particulate, and some of the particles in most samples are modified by the specimen preparation procedures. However, the procedures spec- ified in this International Standard are designed to minimize the disturb- ance of the coliected particulate material, and the effect of those disturbances which do occur can be evaluated. This International Standard describes the method of analysis for a single air filter. However, one of the largest potential errors in characterizing asbestos in ambient atmospheres is associated with the variability be- tween filter samples. For this reason, it is necessary to design a replicate sampling scheme in order to determine this International Standard's ac- curacy and precision. iv a p INTERNATIONAL STANDARD o ISO ISO 10312:1995(E� Ambient air — Determination of asbestos fibres .— Direct-transfer transmission electron microscopy method 1 Scope 1.1 Substance determined ' This International Standard specifies a reference method using transmission electron microscopy for the determination of the concentration of asbestos structures in ambient atmospheres and includes measurement of the lengths, widths and aspect ratios of the asbestos structures. The method allows deter- ' mination of the type(s) of asbestos fibres present. The method cannot discriminate between individuai fibres of the asbestos and non-asbestos analogues of the same amphibole mineral. 1.2 Type of sample The method is defined for polycarbonate capillary-pore filters or cellulose ester (either mixed esters of cellu- lose or cellulose nitrate) filters through which a known volume of air has been drawn. The method is suitable for determination of asbestos in both exterior and building atmospheres. 1.3 Measuring range The range of concentration which can be determined is 50 structures(mm2 to 7 000 structures/mmZ on the filter. The air concentrations represented by these values are a function of the volume of air sampled. There is no lower limit to the dimensions of asbestos fibres which can be detected. In practice, microscopists vary in their ability to detect very small asbestos fibres. Therefore, a minimum length of 0,5 µm has been defined as the shortest fibre to be incorporated in the reported results. 1.4 Limit of detection The limit of detection theoretically can be lowered in- definitely by filtration of progressively larger volumes of air and by extending the examination of the speci- mens in the electron microscope. In practice, the lowest achievabie limit of detection for a particular area of TEM specimen examined is controlled by the total suspended particulate concentration. For total suspended �particulate concentrations of ap- proximately 10 µg/m , corresponding to clean, rural atmospheres, and assuming filtration of 4 000 litres of air, an analytical sensitivity of 0,5 structure(I can be obtained, equivalent to a limit of detection of 1,8 structure�l, if an area of 0,195 mm2 of the TEM specimens is examined. If higher total suspended particulate concentrations are present, the volume of air filtered must be reduced in order to maintain an acceptable particulate loading on the filter, leading to a proportionate increase in the analytical sensitivity. Where this is the case, lower limits of detection can be achieved by increasing the area of the TEM speci- mens that is examined. In order to achieve lower limits of detection tor fibres and bundles longer than 5 µm, and for PCM equivalent fibres, lower magni- fications are spe,cified which permit more rapid ex- amination of larger areas of the TEM specimens when the examination is limited to these dimensions of fi- bre. The direct analyticai method cannot be used if the general particulate loading of the sample coilection filter exceeds approximately 10 µg�cm2 of filter sur- face, which corresponds to approximately 10 % cov- erage of the collection filter by particulate. If the total suspended particulate is largely organic material, the limit of detection can be lowered significantly by using an indirect preparation method. 130 10312:1995(E) � ISO - 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of pubiica- tion, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most re- cent editions of the standards indicated below. Members of IEC and ISO maintain registers of cur- rently valid international Standards. ISO 4225:1994, Air quality — General aspects — Vo- cabulary. ISO 4226:1993, Air quality — General aspects — Units of ineasurement. ISO Standard Handbook No. 2:1993, Quantities and units. ISO Standard Handbook No. 3:1989, Siatistical Meth- ods. 3 Definitions For the purposes of this International Standard, the following definitions apply (see also ISO 4225). 3.1 acicular: The shape of an extremely slender crystal with cross-sectional dimensions which are smail relative to its length, i.e, needle-like. 3.2 amphibole: A group of rock-forming ferromagnesium silicate minerals, closely related in crysta) form and composition, with the nominal for- mula: Ao or �BZC5Tg022(OH,F,CI}2 where A=K,Na B= FeZ+, Mn, Mg, Ca, Na C= AI, Cr, Ti, Fe3+, Mg, Fez+ T= Si, AI, Cr, Fe3+, Ti In some varieties of amphibole, these elements can be partially substituted by �i, Pb or Zn. Amphibole is characterized by a cross-linked double chain of Si-O tetrahedra with a silicon:oxygen ratio of 4:11, by co- lumnar or fibrous prismatic crystals and by good prismatic cleavage in two directions parallel to the 2 crystal faces and intersecting at angles of about 56° and 124°. 3.3 amphibole asbestos: Amphibole in an asbestiform habit. 3.4 analytical sensitivity: The calculated airborne asbestos structure concentration in asbestos structures/litre, equivalent to counting of one asbestos structure in the analysis. The method in this International Standard does not specify an analytical sensitivity. 3.5 asbestiform: A specific type of mineral fibrosity in which the fibres and fibrils possess high tensile strength and fiexibility. 3.6 asbestos: A term applied to a group of silicate minerals belonging to the serpentine and amphibole groups which have crystallized in the asbestiform habit, causing them to be easily separated into long, thin, strong fibres when crushed or processed. The Chemical Abstracts Service Registry Numbers of the most common asbestos varieties are: chrysotile (12001-29-5), crocidolite (1 200 1-28-4), grunerite asbestos (amosite) (12172-73-5), anthophyliite asbestos (77536-67-5), tremolite asbestos (77536-68-6) and actinolite asbestos (77536-66-4�. 3.7 asbestos structure: A term applied to any con- nected or overlapping grouping of asbestos fibres or bundles, with or without other particles. 3.8 aspect ratio: The ratio of length to width of a particle. 3.9 blank: A structure count made on TEM speci- mens prepared from an unused filter, to determine the background measurement. 3.10 camera length: The equivalent projection length between the specimen and its electron dif- fraction pattern, in the absence of lens action. 3.11 chrysotile: A fibrous mineral of the serpentine group which has the nominal composition Mg3s�2�5���'i�q Most natural chrysotile deviates little from this nomi- nal composition. In some varieties of chrysotile, minor substitution of silicon by AI3+ may occur. Minor sub- stitution of magnesium by AI3+, Fe2�, Fe3+ Niz+ Mn2+ and Co2+ may aiso be present. Chrysotile is the most prevalent type of asbestos. 3.12 cleavage: The breaking of a mineral along one of its crystallographic directions. = . o ISO ISO 1Q312:1995jE) F 3.13 cleavage fragment: A fragment of a crystal that is bounded by cleavage faces. 3.14 ciuster: A structure in which two or more fi- bres, or fibre bundles, are randomly oriented in a connected grouping. 3.15 d-spacing: The distance between identical ad- jacent and paraliel planes of atoms in a crystal. 3.16 electron diffraction: A technique in electron microscopy by which the crystal structure of a speci- men is examined. 3.17 electron scattering power: The extent to which a thin layer of substance scatters e�ectrons from their original directions. 3.18 energy dispersive X-ray analysis: Measure- ment of the energies and intensities of X-rays by use of a solid state detector and muitichannel analyser system. 3.19 eucentric: The condition when the area of in- terest of an object is placed on a tilting axis at the intersection of the electron beam with that axis and is in the plane of focus. 3.20 field blank: A filter cassette which has been taken to the sampling site, opened, and then closed. Such a filter is used to determine the background structure count for the measurement. 3.21 fibril: A single fibre of asbestos, which cannot be further separated longitudinally into smaller com- ponents without losing its fibrous properties or ap- pearances. 3.22 fibre: An elongated particle which has parallel or stepped sides. For the purposes of this Interna- tional Standard, a fibre is defined to have an aspect ratio equal to or greater than 5:1 and a minimum length of 0,5 µm. 3.23 fibre 6undle: A structure composed of parallel, smaller diameter fibres attached along their lengths. A fibre bundle may exhibit diverging fibres at one or both ends. 3.24 fibrous structure: A fibre, or connected grouping of fibres, with or without other particles. 3.25 habit: The characteristic crystal growth form, (or combination of these forms), of a mineral, includ- ing characteristic irregularities. 3.26 limit of detection: The caiculated airborne asbestos structure concentration in structures per li- tre, equivalent to counting 2,99 asbestos structures in the analysis. 3.27 matrix: A structure in which one or more fi- bres, or fibre bundles, touch, are attached to, or par- tially concealed by, a single particle or connected group of nonfibrous particles. 3.28 Milier index: A set of either three or four inte- ger numbers used to specify the orientation of a crystallographic piane in relation to the crystal axes. 3.29 PCM equivalent fibre: A fibre of aspect ratio greater than or equal to 3:1, longer than 5 µm, and which has a diameter between 0,2 µm and 3,0 µm. 3.30 PCM equivalent structure: A fibrous structure of aspect ratio greater than or equal to 3:1, longer than 5 µm, and which has a diameter between 0,2 µm and 3,0 µm. 3.31 primary structure: A fibrous structure that is a separate entity in the TEM image. 3.32 replication: . A procedure in electron microscopy specimen preparation in which a thin copy, or replica, of a surface is made. 3.33 selected area electron diffraction: A tech- nique in electron microscopy in which the crystal structure of a small area of a sample is examined. 3.34 serpentine: A group of common rock-forming minerals having the nominal formula M9sS�2�efOH)4 3.35 structure: A single fibre, fibre bundle, cluster or matrix. 3.36 twinning: The occurrence of crystals of the same species joined together at a particular mutual orientation, such that the relative orientations are re- lated by a definite law. 3.37 unope�ed fibre: An asbestos fibre bundle of large diameter which has not been separated into its constituent fibrils or fibres. 3.38 zone-axis: The line or crystallographic direction through the centre of a crystal which is parailel to the intersection edges of the crystal faces defining the crystal zone. 4 Principle A sample of airborne particulate is coliected by draw- ing a measured volume of air through either a 3 ISO 10312:1995�E) capillary-pore polycarbonate membrane filter of maxi- mum pore size 0,4 µm or a cellulose ester (either mixed esters of cellulose or cellulose nitrate) mem- brane filter of maximum pore size 0,45 µm by means of a battery-powered or mains-powered pump. TEM specimens are prepared from polycarbonate filters by appiying a thin film of carbon to the filter surface by vacuum evaporation. Small areas are cut from the carbon-coated filter, supported on TEM specimen grids, and the filter medium is dissolved away by a solvent extraction procedure. This procedure leaves a thin film of carbon which bridges the openings in the TEM specimen grid, and which supports each particle from the original filter in its original position. Cellulose ester filters are chemica(ly treated to collapse the pore structure of the filter, and the surface of the collapsed fiiter is then etched in an oxygen plasma to ensure that ail particles are exposed. A thin film of carbon is evaporated onto the filter surface and smali areas are cut from the filter. These sections are supported on TEM specimen grids and the filter medium is dis- soived away by a solvent extraction procedure. The TEM specimen grids from either preparation method are examined at both low and high magni- fications to check that they are suitable for analysis before carrying out a quantitative structure count on randomly-selected grid openings. In the TEM analysis, electron diffraction (ED) is used to examine the crystal structure of a fibre, and its elementai composition is determined by energy dispersive X-ray analysis (EDXA). For a number of reasons, it is not possibie to identify each fibre unequivocally, and fibres are clas- sified according to the techniques which have been used to identify them. A simple code is used to re- cord, for each fibre, the manner in which it was cias- sified. The fibre classification procedure is based on successive inspection of the morphology, the electron diffraction pattern for a selected area, and the qual- itative and quantitative energy dispersive X-ray ana- lyses. Confirmation of the identification of chrysotile is done only by quantitative ED, and confirmation of amphibole is done only by quantitative EDXA and qua�titative zo�e axis ED. In addition to isolated fibres, ambient air samples of- ten contain more complex aggregates of fibres, with or without other particles. Some particles are com- posites of asbestos fibres with other materials. Indi- vidual fibres and structures that are more complex are referred to as "asbestos structures". A coding system is used to record the type of fibrous structure, and to provide the optimum description of each of these complex structures. The two codes remove the re- quirement to interpret the structure counting data from the microscopist, and allow this evaluation to be made later without the requirement for re- 4 examination of the TEM specimens. Several leveis of analysis are specified, the higher levels providing a more rigorous approach to the identification of fibres. The procedure permits a minimum required fibre identification criterion to be defined on the basis of previous knowledge, or lack of it, about the particular sample. Attempts are then made to achieve this min- imum criterion for each fibre, and the degree of suc- cess is recorded for each fibre. The lengths and widths of all classified structures and fibres are re- corded. The number of asbestos structures found on a known area of the microscope sample, together with the equivalent volume of air filtered through this area, is used to calculate the airborne concentration in asbestos structuresJlitre of air. 5 Symbols of units and abbreviations 5.1 Symbols of units (see also ISO 4226 and ISO No. 2) eV = electron volt kV = kilovolt I/min = litres per minute µg = microgram (10-6 gram) µm = micrometre (10-6 metre) nm = nanometre (10-9 metre) W = watt 5.2 Abbreviations DMF Dimethylformamide DE Electron diffraction EDXA Energy dispersive X-ray analysis FWHM HEPA MEC PC PCM SAED SEM STEM TEM Full width, half maximum High efficiency particle absolute Mixed esters of cellulose Polycarbonate Phase contrast optical microscopy Selected area electron diffraction Scanning electron microscope Scanning transmission electron microscope Transmission electron microscope o ISO UICC Union Internationale Contre le Cancer 6 Reagents During the analysis, unless otherwise stated, use only reagents of recognized analytical grade and water (6.11. WARNING — Use the reagents in accordance with the appropriate hea{th and safety regulations. 6.1 water, fibre-free. A supply of freshly distilled, fibre-free water, or an- other source of fibre-free, pyrogen-free water shall be used. 6.2 Chloroform, analytical grade, distilled in glass, preserved with 1 % (VM ethanol. 6.3 1-Methyi-2-pyrrolidone. 6.4 Dimethylformamide. 6.5 Glacial acetic acid. 6.6 Acetone. 7 Apparatus 7.1 Air sampling — Equipment and consumable supplies 7.1.1 Filter cassette Field monitors, comprising 25 mm to 50 mm diam- eter three-piece cassettes, with cowls which project less than 2 cm in front of the filter surface shall be used for sample collection. The cassette shall be loaded with either a capillary pore polycarbonate fiiter of maximum pore size 0,4 µm or an MEC or cellulose nitrate filter of maximum pore size 0,45 µm. Either type of filter shall be backed by a 5 µm pore size MEC or cellulose nitrate filter, and supported by a ceilulose back-up pad. When the filters are in position, an elas- tic cellulose band or adhesive tape shall be applied to prevent air leakage. Suitable precautions shall be taken to ensure that the filters are tightly clamped in the assembly, so that significant air leakage around the filter cannot occur. Representative filters from the filter lot shall be ana- lysed as specified in 9.7 for the presence of asbestos structures before any are used for air sample coi- lection. ISO 10312:1995(E) 7.1.2 Sampling pump The sampling pump shall be capable of a flow-rate sufficient to achieve the desired analytical sensitivity. The face velocity through the filter shall be between 4,0 cm/s and 25,0 cm/s. The sampling pump used shall provide a non-fluctuating airflow through the fil- ter, and shali maintain the initial volume flow-rate to within ± 10 % throughout the sampling period. A constant flow or critical orifice controlied pump meets these requirements. Flexible tubing shall be used to connect the filter cassette to the sampling pump. A means for calibration of the flow-rate of each pump is also required. 7.1.3 Stand A stancl shall be used to hold the filter cassette at the desired height for sampling, and shall be isolated from the vibrations of the pump (7.1.2). 7.1.4 Variable area flowmeter A calibrated variable are a flowmeter with a range of approximately 1 I/min to 10 I/min is required for cali- bration of the air sampling system. The variable area flowmeter shall be cleaned before use to avoid transfer of asbestos contamination from the flowmeter to the sample being collected. 7,2 Specimen preparation laboratory Asbestos, particularly chrysotile, is present in varying quantities in many laboratory reagents. Many building materials also contain significant amounts of asbestos or other mineral fibres which may interfere with the analysis if they are inadvertentiy introduced during preparation of specimens. It is most important to en- sure that, during preparation, contamination of TEM specimens by any extraneous asbestos fibres is min- imized. All specimen preparation steps shali therefore be performed in an environment where contamination of the sample is minimized. The primary requirement of the sample preparation laboratory is that a blank determination shall yield a result which will meet the requirements specified in 9.7. A minimum facility considered suitable for preparation of TEM specimens is a laminar flow hood with positive pressure. How- ever, it has been established that work practices in specimen preparation appear to be more important than the tape of clean handling facilities in use. Prep- aration of samples shall be carried out only after ac- ceptable blank values have been demonstrated. NOTE 1 It is recommended that activities invoiving ma- nipulation of bulk asbestos samples not be performed in the 5 ISO 10312:1995(E) same area as TEM specimen preparation, because of the possibilities of contaminating the TEM specimens. 7.3 Equipment for analysis 7.3.1 Transmission electron microscope A TEM operating at an accelerating potential of 80 kV to 120 kV, with a resolution better than 1,0 nm, and a magnification range of approximately x 300 to x 100 000 shall be used. The ability to obtain a direct screen magnification of about x 100 000 is � ISO " necessary for inspection of fibre morphology; this magnification may be obtained by supplementary op- tical enlargement of the screen image by use of a binocular if it cannot be obtained directly. It is also required that the viewing screen of the microscope be calibrated such that the lengths and widths of fibre images down to 1 mm width can be measured in in- crements of 1 mm, regardless of image orientation. This requirement is often fulfiiled through the use of a fluorescent screen with calibrated gradations in the form of circles, as shown in figure 1. 4 5 6 7 Figure 1— Example of calibration markings on TEM viewing screen 6 ti � o ISO : For Bragg angles less than 0,01 rad, the TEM shall be capable of performing ED from an area of 0,6 µm2 or less, selected from an in-focus image at a screen magnification of x 20 000. This performance require- ment defines the minimum separation between parti- cles at which independent ED patterns can be obtained from each particle. If SAED is used, the performance of a particular instrument may normally be calculated using the following equation A= 0,785 4 x� M+ 2 OO0058312 / where A is the effective SAED area, in square micrometres; D is the diameter, in micrometres, of the SAED aperture; M is the magnification of the objective lens; CS is the spherical aberration coefficient, in millimetres, of the objective lens; 8 is the maximum required Bragg angle, in radians. It is not possible to reduce the effective SAED area indefinitely by the use of progressively smaller SAED apertures, because there is a fundamental limitation imposed by the spherical aberration coefficie�t of the objective lens. If zone-axis ED analyses are to be performed, the TEM shall incorporate a goniometer stage which per- mits the TEM specimen to be either a) rotated through 360°, combined _ with tilting through at least + 30° to — 30° about an axis in the plane of the specimen; b? tilted through at least + 30° to — 30° about two perpendicular axes in the plane of the specimen. _ The analysis is greatly facilitated if the goniometer permits eucentric tilting, although this is not essential. If EDXA and zone-axis ED are required on the same fibre, the goniometer shall be of a type which permits tilting of the specimen and acquisition of EDXA spec- tra without changing the specimen holder. The TEM shall have an illumination and condenser lens system capable of forming an electron probe of diameter less than 250 nm. NOTE 2 Use of an anti-contamination trap around the specimen is recommended if the required instrumental performance is to be obtained. ISO 10312:1995(E) 7.3.2 Energy dispersive X-ray analyser The TEM shall be equipped with an energy. dispersive X-ray analyser capabie of achieving a resolution better than 180 eV (FWHM} on the MnKa. Since the per- formance of individua) combinations of TEM and EDXA equipment is dependent on a number of ge- ometrical factors, the required performance of the combination of the TEM and X-ray analyser is speci- fied in terms of the measured X-ray intensity obtained from a fibre of small diameter, using a known electron beam diameter. Solid state X-ray detectors are least sensitive in the low energy region, and so measure- ment of sodium in crocidolite shall be the perform- ance criterion. The combination of electron microscope and X-ray analyser shall yield, under rou- tine analytical conditions, a background-subtracted NaKa integrated peak count rate of more than 1 count per second (cps) from a fibre ot UICC crocidolite, 50 nm in diameter or smaller, when irradiated by an electron probe of 250 nm diameter or smaller at an accelerating potential of 80 kV. The peak/background ratio for this performance test shall exceed 1,0. The EDXA unit shall provide the means for subtraction of the background, identification of elementai peaks, and calculation of background-subtracted peak areas. 7.3.3 Computer Many repetitive numericai calculations are necessary, and these may be performed conveniently by rela- tively simple computer programmes. For analyses of zone-axis ED pattern measurements, a computer with adequate memory is required to accommodate the more complex programmes involved. 7.3.4 Plasma asher For preparation of TEM specimens from MEC filters, a plasma asher, with a radio frequency power rating of 50 W or higher, shall be used to etch the surface of collapsed MEC filters. The asher shall be supplied with a controlled oxygen flow, and shall be modified, if necessary, to provide a vaive to control the speed of air admission 'so that rapid air admission does not disturb particulates from the surface of the filter after the etching step. NOTE 3 It is recommended that filters be fitted to the oxygen suppiy and the air admission line. 7.3.5 Vacuum coating unit A vacuum coating unit capable of producing a vacuum better than 0,013 Pa shall be used for vacuum de- position of carbon on the membrane filters. A sampie 7 (SO 10312:1995(E) holder is required which will allow a glass microscope slide to be continuously rotated during the coating procedure. NOTE 4 A mechanism which also allows the rotating slide to be tilted through an angle of approximately 45° during the coating procedure is recommended. A liquid ni- trogen cold trap above the diffusion pump may be used to minimize the possibiliry of contamination of the filter sur- faces by oil from the pumping system. The vacuum coating unit may also be used for deposition of the thin film of gold, or other calibration material, when it is required on TEM specimens as an internal calibration of ED patterns. 7.3.6 Sputter coater A sputter coater with a gold target may be used for deposition of gold onto TEM specimens as an integral calibration of ED patterns. Other calibration materials are acceptable. Experience has shown that a sputter coater aliows better control of the thickness of the calibration material. 7.3.7 Solvent washer f Jaffe washer) The purpose of the Jaffe washer is to ailow dissol- ution of the filter polymer while leaving an intact evaporated carbon film supporting the fibres and other particles from the filter surface. One design of Glass Petri dish (fd 100 mm x 15 mn � ISO a washer which has been found satisfactory for vari- ous solvents and filter media is shown in figure 2. I� general, either chloroform or 1-methyl-2-pyrrolidone has been used for dissolving polycarbonate filters and dimethylformamide or acetone has been used for dissolving MEC or cellulose nitrate filters. The higher evaporation rates of chloroform and acetone require that a reservoir of 10 ml to 50 ml of solvent be used, which may need replenishment during the procedure. Dimethylformamide and 1-methyi-2-pyrrolidone have lower vapour pressures and much smaller volumes of solvent may be used. It is recommended that ail washers be used in a fume hood, and when speci- mens are not being inserted or removed, the Petri dish lid shall be in place during the solvent dissolution. The washer shali be cleaned before it is used for each batch of specimens. 7.3.8 Condensation washer For more rapid dissolution of the filter polymer, or if difficulties are experienced in dissolving the filter polymer, use a condensation washer, consisting of a flask, condenser and cold finger assembly, with a heating mantle and means for contro►ling the temper- ature. A suitable assembly is shown in figure 3, using either acetone or chloroform as the solvent, depend- ing on the type of filter. Dimensions in centimetres Electron microscooe NOTE — Solvent is added untii the meniscus contacts the underside of the stainless steel mesh bridge. Figure 2— Example of design of soivent washer (Jaffe washerl 8 �tainless steel mesh ��idge (50 mesh) o ISO Condenser Specimen ISO 10312:1995(E Water drain Cold finger E- Cold water source �nt nostaticaily controtled ng mantle Figure 3— Example of design of condensation washer 7.3.9 Slide warmer or oven Use either a slide warmer or an oven for heating slides during the preparation of TEM specimens from MEC or cellulose nitrate filters. It is required to main- tain a temperature of 65 °C to 70 °C. 7.3.10 Ultrasonic bath An ultrasonic bath is necessary for cleaning the appa- ratus used for TEM specimen preparation. 7.3.11 Carbon grating replica A carbon grating replica with about 2 000 parallel lines per millimetre shall be used to calibrate the magni- fication of the TEM. 7.3.12 Calibration specimen grids for EDXA TEM specimen grids prepared from dispersions of calibration minerals are required for calibration of the EDXA system. Some suitable calibration minerals are riebeckite, chrysotile, halloysite, phlogopite, woilas- tonite and bustamite. The mineral used for calibration of the EDXA system for sodium shall be prepared using a gold TEM grid. 7.3.13 Carbon rod sharpener The use of necked carbon rods, or equivalent, allows the carbon to be evaporated onto the filters with a minimum of heating. 7.3.14 Disposable tip micropipettes A disposable tip micropipette, capable of transferring a volume of approximately 30 µl, is necessary for the preparation of TEM specimen grids from MEC filters. 7.4 Consumable supplies 7.4.1 Copper electron microscope grids Copper TEM grids with 200 mesh are recommended. Grids which have grid openings of uniform size such that they meet the requirement specified in 9.62 shall be chosen. To facilitate the relocation of individual grid openings for quality assurance purposes, the use of grids with numerical or alphabetical indexing of indi- vidual grid openings is recommended. 9 130 10312:9995(E) 7.4.2 Gold electron microscope grids Gold TEM grids with 200 mesh are recommended to mount TEM specimens when sodium measurements are required in the fibre identification procedure. Grids which have grid openings of uniform size such that they meet the requirement specified in 9.6.2 shall be chosen. To facilitate the relocation of individual grid openings for quality assurance purposes, the use of g�ids with numerical or alphabetical indexing of indi- vidual grid openings is recommended. 7.4.3 Carbon rod electrodes Spectrochemicaliy pure carbon rods, shall be used in the vacuum evaporator (7.3.5) during carbon coating of filters. 7.4.4 Routine electron microscopy tools and supplies Fine-point tweezers, scalpel holders and blades, mi- croscope slides, double-coated adhesive tape, lens tissue, gold wire, tungsten filaments and other routine supplies are required. 7.4.5 Refere�ce asbestos samples Asbestos samples, shall be for preparation of refer- ence TEM specimens of the primary asbestos min- erals. The UICC set of minerals is suitable for this purpose. 8 Air sample collection The desired analytical sensitivity is a parameter that shall be established for the analysis prior to sample collection. It is defined as the structure concentration corresponding to the detection of one structure in the analysis. For direct transfer methods of TEM speci- men preparation, the analytical sensitivity is a function of the volume of air sampled, the active area of the collection filter, and the area of the TEM specimen over which structures are counted. If total airborne dust levels are high, it may be necessary to terminate sampling before the required volume has been sam- pled. If this happens, the analytical sensitivity required can be achieved only by counting structures on more grid openings, or by selective concentration of asbestos structures using an indirect TEM specimen preparation technique. Select the sampling rate and the period of sampling to yield the required analytical sensitivity, as detailed in table 1. Before air samples 10 � ISO are collected, unused filters shall be analysed as de- scribed in 9.7 to determine the mean asbestos struc- ture count for blank filters. Air samples shall be collected using filter cassettes l7.1.1). During sampling, the cassette shall be sup- ported on a stand (7.1.3) which is isolated from the vibrations of the pump (7.1.2). The cassette shall be held facing verticaily downwards at a height of ap- proximately 1,5 m to 2,0 m above ground/floor level, and shali be connected to the pump with a flexible tube. Measure the sampiing flow-rate at the front end of the cassette, both at the beginning and end of the sampling period, using a calibrated variable area fiowmeter (7.1.4) temporarily attached to the iniet of the cassette. The mean value of these� two mea- surements shall be used to calculate the total air vol- ume sampled. Basic strategies for monitoring environmental sources of airborne asbestos are described in annex G. After sampling, a cap shall be placed over the open end of the cassette, and the cassette packed with the fiiter face-upwards for return to the laboratory. Field blank filters shall also be included, as specified in 9.7, and subrnitted to the remaining analytical procedures along with the samples. NOTES 5 In table 1 a collection filter area of 385 mm2 is assumed, and the TEM grid openings are assumed to be 85 µm2 square. The limit of detection is defined as the upper 95 °/a confidence limit of the Poisson distribution for a count of 0 structures. In the absence of background, this is equal to 2,99 times the analytical sensitivity. Backgrounds that are different from 0 observed during analysis of blank filters will degrade the limit of detection. 6 The analytical sensitivity S, expressed in number of structures per litre, is calculated using the following equation: s kA rV 9 where A� is the active area, in square millimetres, of sampie coilection filter; A9 is the mean area, in square miilimetres, of grid openings examined; is the number of grid openings examined; is the volume of air sampied, in litres. o ISO ISO 10312:1995(E) Table 1— Examples of the minimum number of grid openings requi�ed to achieve a particular analytical sensitivity and �imit of detection Analytical Limit of Volume of air sampled (litres) sensitivity detection structures(I structures(I 500 1 000 2 000 3 000 4 000 5 000 0,1 0,30 1066 533 267 178 134 107 0,2 0,60 533 267 134 89 67 54 0,3 0,90 356 178 89 60 45 36 0,4 1,2 267 134 67 45 34 27 0,5 1,5 214 107 54 36 27 22 0,7 2,1 153 77 39 26 20 16 1,0 3,0 107 54 27 18 14 11 2,0 6,0 54 27 14 9 7 6 3,0 9,0 36 18 9 6 5 4 4,0 12 27 14 7 5 4 4 5,0 15 22 11 6 4 4 4 7,0 21 16 8 4 4 4 4 10 30 11 6 4 4 4 4 9 Procedure for analysis 9.1 General The techniques used to prepare TEM specimens are different for polycarbonate and cellulose ester filters. The preparation method to be used shall be either 9.3 or 9.4, depending on the type of inembrane filter used for air sampling. Cleaning of the sample cassettes before they are opened, preparation of the carbon evaporator, criteria for acceptable specimen grids, and the requirement for blank determinatioris are identical for the two preparation techniques. TEM examination, structure counting, fibre identification and reporting of results are independent of the type of filter or preparation technique used. The ability to meet the blank sample criteria is de- pendent on the cleanliness of equipment and sup- plies. Consider all supplies such as microscope siides and glassware as potential sources of asbestos con- tamination. It is necessary to wash all glassware be- fore it is used. Wash any tools or giassware which come into contact with the air sampling filters or TEM specimen preparations both before use and between handling of individual samples. Where possible, disposable supplies should be used. 9.2 Cleaning of sample cassettes Asbestos fibres can adher to the exterior surfaces of air sampling cassettes; and these fibres can be inad- vertently transferred to the sampie during handling. To prevent this possibility of contamination, and after ensuring that the cassette is tightly sealed, wipe the exterior surfaces of each sampling cassette before it is placed in the clean facility or laminar flow hood. 9.3 Direct preparation of TEM specimens from polycarbonate filters 9.3.1 Selection of fiiter area for carbon coating Use a cleaned microscope slide to support represen- tative portions of polycarbonate filter during the car- bon evaporation. Double-coated adhesive tape is used to attach the filter portions to the glass slide. Take care not to stretch the polycarbonate filters during handling. Using freshly cleaned tweezers, remove the polycarbonate filter from the sampling cassette, and place it on to a second cleaned glass microscope siide which is used as a cutting surface. Using a freshly cleaned curved scalpel blade, cut the filter by rocking the blade from the point, pressing it into contact with the filter. Repeat the process as necessary. Several such portions may be mounted on the same micro- scope slide. The scalpei blade and tweezers shall be washed and dried between the handling of each filter. Identify the filter portions by writing on the glass slide. 9.3.2 Carbo� coating of filter portions Place the glass slide hoiding the filter portions on the rotation-tilting device; approximately 10.cm to 12 cm 11 1�0 10312:1995(E) from the evaporation source, and evacuate the evaporator chamber l7.3.5) to a vacuum better than 0,013 Pa. The evaporation of carbon shall be per- formed in very short bursts, separated by a few sec- onds to allow the electrodes to cool. If evaporation of carbon is too rapid, the strips of polycarbonate filter will begin to curl, and cross-linking of the surface wili occur. This cross-linking procedures a layer of polymer which is relatively insoluble in organic solvents, and it will not be possible to prepare satisfactory TEM specimens. The thickness of carbon required is de- pendent on the size of particles on the filter, and ap- proximately 30 nm to 50 nm has been found to be satisfactory. If the carbon film is too thin, large parti- cles will break out of the fiim during the later stages of preparation, and there wili be few complete and undamaged grid openings on the specimen. Too thick a carbon film will lead to a TEM image which is lack- ing in contrast, and the ability to obtain ED patterns wili be compromised. The carbon film thickness should be the minimum possible, while retaining most of the grid openings of the TEM specimen intact. 9.3.3 Preparation of the Jaffe washer Place several pieces of lens tissue, as shown in figure 2, on the stainless steel bridge (7.1.3) and fill the washer (see 7.3.7) with chloroform (6.2} or 1-methyl-2-pyrrolidone (6.3) to a level where the meniscus contacts the underside of the mesh, re- sulting in saturation of the lens tissue. 9.3.4 Placing of specimens in the Jaffe washer Using a curved scalpel blade, cut three 3 mm square pieces of carbon-coated polycarbonate filter form the carbon-coated filter portion. Select three squares to represent the centre and the periphery of the active surface of the filter. Place each square of filter, carbon side up, on a TEM specimen grid, and place the grid and filter on the saturated lens tissue in the Jaffe washer. Place the three specimen grids from one sample on the same piece of lens tissue. Any number of separate pieces of lens tissue may be placed in the same Jaffe washer. Cover the Jaffe washer with the lid, and allow the washer to stand for at least 8 h. NOTE 7 It has been found that some polycarbonate fii- ters will not completely dissolve in the Jaffe washer, even after exposure to chloroform for as long as 3 d. This prob- lem is more severe if the surface of the filter was over- heated during the carbon evaporation. it has been found that the problem of residual undissolved filter polymer can be overcome in several ways: a) condensation washing of the grids, using chloroform as the solvent, after the initial Jaffe washer treatment, can 12 o ISO often remove much of the residuai filter medium in a period of approximately 30 min. To carry out this pro- cedure, transfer the piece of lens tissue supporting the specimen grids to the cold finger of the condensation washer (7.3.8), which has achieved stable operating conditions. Operate the washer for approximately 30 min after inserting the grids; b) used in a Jaffe washer, 1-methyl-2-pyrrolidone has been found to be a more effective solvent than chloroform for polycarbonate filters. This soivent is more effective if the lens paper is not used and grids are placed di- rectly on the stainless steel mesh of the Jaffe washer. A dissolution period of 2 h to 6 h has been found to be satisfactory. After dissolution is complete, remove the stainless steel mesh from the Jaffe washer and allow the grids to dry. 1-methyi-2-pyrrolidone evaporates very slowly. If it is required to dry the grids more rapidiy, transfer the stainless steel bridge into another Petri dish, and add water (6.1) until the meniscus contacts the underside of the mesh. After approximately 15 min, remove the mesh and allow the grids to dry. If it is desired to retain water-soluble particle species on the TEM grids, ethanol may be used instead of water (6.1 � for the second wash; c) a mixture of 20 °/a 1,2-diaminoethane [ethylenediamine] and 80 % 1-methyl-2-pyrrolidone, used in a Jaffe washer, completely dissolves polycarbonate filters in 15 min, even if the surface oi the filter has been overheated. To use this solvent, place the grids directiy on the stainless steel mesh of the Jaffe washer, do not use the lens paper. After a period of 15 min, transfer the stainless steel bridge into another Petri dish, and add water (6.1) until the meniscus contacts the underside of the mesh. After approximately 15 min, remove the mesh and allow the grids to dry. If it is desired to retain water-soluble par- ticle species on the TEM grids, ethanol may be used instead of water (6.1) for the second wash. 9.3.5 Rapid preparation of TEM specimens from PC flters TEM specimens can be prepared rapidly from PC fil- ters, if desired, by washing for approximately 1 h in a Jaffe washer, foilowed by washing for 30 min in a condensation washer using chloroform as the solvent. The alternative filter dissolution procedures described in note 7 may also be used. 9.4 Direct preparation of TEM specimens from cellulose ester filters 9.4.1 Selection of area of filter for preparation Using clean tweezers, remove the filter from the filter cassette, and place it on a cleaned microscope slide. Using a clean, curved scalpel blade, cut out a portion of the filter. o ISO 9.4.2 Preparation of solution for collapsing ceilulose ester filters Mix 35 ml of dimethylformamide f 6.4), and 15 ml of glacial acetic acid (6.5) with 50 ml of water (6.1). Store this mixture in a clean bottle, The mixture is stable and suitable for use for up to 3 months after prepara- tion. 9.4.3 Fiiter collapsing procedure Using a micro�pipette with a disposable tip (7.3.14), place 15 µl/cm to 25 µlJcm2 of the solution prepared in 9.4.2 on a cleaned microscope slide, and using the end of the pipette tip, spread the liquid over the area to be occupied by the filter portion. Place the filter portion, active surface upwards, on top of the sol- ution, lowering the edge of the filter at an angle of about 20° so that air bubbles are not created. Remove any solution not absorbed by the filter by allowing a paper tissue to contact the liquid at the edge of the filter. More than one fiiter portion may be placed on one slide. Place the slide either on a thermostatically controlled slide warmer (7.3.9) at a temperature of 65 °C to 70 °C, or in an oven (7.3.9) at this temper- ature, for 10 min. The fiiter collapses slowly to about 15 % of its original thickness. The procedure leaves a thin, transparent polymer film, with particles and fi- bres embedded in the upper surface. 9.4.4 Plasma etching of the filter surface The optimum conditions and time for plasma etching (see 7.3.4) have been determined experimentally from the recovery of fine chrysotile fibrils on 0,8 µm pore size MEC filters. The conditions required in a particular plasma asher shall be established using the procedure specified in annex A. Place the microscope slide holding the collapsed filter portions in the plasma asher, and etch for the time and under the conditions � determined. Take care to ensure that the correct conditions are respected. After etching, admit air slowly to the chamber and remove the microscope slide. Adjust the air admission valve of the plasma asher such that the time taken for the chamber to reach at- mospheric pressure exceeds 2 min. Rapid air admis- sion may disturb particulates on the surface of the etched filter. 9.4.5 Carbon coating Coat the microscope slide holding the collapsed filter portions with carbon as specified in 9.3.2. ISO 10312:1995(E) 9.4.6 Preparation of the Jaffe washer Place several pieces of lens tissue on the stainless steel bridge, and fiil the washer with dimethylformamide (6.4) or acetone (6.6) to a level where the meniscus contacts the underside of the mesh, resulting in saturation of the lens tissue. 9.4.7 Placing of specimens in the Jaffe washer Place the specimens in the Jaffe washer as specified in 9.3.4. Specimens are normaliy cleared after ap- proximately 4 h. 9.4.8 Rapid preparation of TEM specimens from cellulose ester fiiters An alternative washing procedure may be used to prepare TEM specimens from cellulose ester filters more rapidiy than can be achieved by the Jaffe washing procedure. After the specimens have been washed in a Jaffe washer for approximately 1 h, transfer the piece of lens tissue supporting the specimens to the cold finger of a condensation washer (7.3.8) operating with acetone as the soivent because dimethylformamide shall not be used in a conde�sation washer. Operate the condensation washer for approximately 30 min. This treatment re- moves all the remaining filter polymer. 9.5 Criteria for acceptable TEM specimen grids Valid data cannot be obtained unless the TEM speci- mens meet specified quality criteria. Examine the TEM specimen grid in the electron microscope at a sufficiently low magnification (x 300 to x 1 000) for complete grid openings to be inspected. Reject the grid if a? the TEM specimen has not been cleared of filter medium by the filter dissolution step. If the TEM specimen exhibits areas of undissolved filter me- dium, and if at least two of the three specimen grids are not cleared, either additional washing with solvent shall be carried out, or new speci- mens shall be prepared from the filter; b) the sample is overloaded with particulate. If the specimen grid exhibits more than approximately 10 % obscuration on the majority of the grid openings, the specimen shall be designated as overloaded. This filter cannot be alanysed satis- factorily using the direct preparation methods be- cause the grid is too heavily loaded with debris to allow separate examination of individual particies by ED and EDXA, and� obscuration of fibres by 13 1�0 10312:1995(E) other particulates may lead to underestimation of the asbestos structure count; c) the particulate deposits on the specimen are not uniformly distributed from one grid opening to the next. �f the particulate deposits on the specimen are obviously not uniform from one grid opening to the next, the specimen shall be designated as non-uniform. This condition is a function either of the air sampiing conditions or of the fundamentai nature of the airborne particulate. Satisfactory analysis of this filter may not be possible unless a large number of grid openings is examined; d) the TEM grid is too heavily loaded with fibrous structures to make an accurate count. Accurate counts cannot be made if the grid has more than approximately 7 000 structures/mmZ; or e) more than approximately 25 % of the grid openings have broken carbon film over the whole grid opening. Since the breakage of carbon film is usually more frequent in areas of heavy deposit, counting of the intact openings can lead to an underestimate of the asbestos structure count. NOTE 8 If the specimens are rejected because un- acceptable numbers of grid openings exhibit broken carbon replica, an additional carbon coating may be ap- plied to the carbon coated filter, and new specimen grids prepared. The larger particles can often be sup- ported by using a thicker carbon film. If this action does not produce acceptable specimen grids, this fiiter can- not be analysed using the direct preparation methods. If one or more of the conditions described in bi, c), d) or e) exists, it may not be possible to analyse the sample by this method. 9.6 Procedure for structure counting by TEM 9.6.1 General The examination consists of a count of asbestos structures which are present on a specified number of grid openings. Fibres are classified into groups on the basis of morphological observations, ED patterns and EDXA spectra. The totai number of structures to be counted depends on the statistical precision de- sired. In the absence of asbestos structures, the area of the TEM specimen grids which must be examined depends on the analytical sensitivity required. The precision of the structure count depe�ds not only on the totai number of structures counted, but also on their uniformity from one grid opening to the next. Additionai structure counting will be necessary if greater precision is required. 14 � ISO In order that the estimate of the structure density on the sampling filter shall not be based on the smali area represented by one specimen grid, grid openings shall be examined on two of the three specimen grids prepared. Then combine the results in the caiculation of the structure density. Structure counts shall be made at a magnification of approximately x 20 000, and shall be terminated at the end of the examination of the grid opening on which the 100th asbestos structure is observed, except that the count shall be continued until a minimum of 4 grid openings have been examined. Otherwise, the structure count shall continue to that number of grid openings at which the specified analytical sensitivity has been achieved. NOTE 9 The normal range for the number of grid openings which should be examined is from 4 to 20. If in- sufficient air has been sampled through the filter, the cal- culation in 9.6.4 can indicate that an impractically large number of grid openings should be examined. When this situation occurs, a larger value of ana�yticai sensitivity may have to be accepted. 9.6.2 Measurement of inean grid opening area The mean grid opening area shall be measured for the type of TEM specime� grids in use. The standard de- viation of the mean of 10 openings selected from 10 grids shouid be less than 5%. As an optional proce- dure, or if the 5% standard deviation criterion cannot be demonstrated, the dimensions of each grid open- ing examined in the TEM shall be measured at a cali- brated magnification. 9.6.3 TEM alignment and calibration procedures Before structure counting is performed, align the TEM according to instrumental specifications. Calibrate the TEM and EDXA system according to the procedures specified in annex B. 9.6.4 Determination of stopping point Before structure counting is begun, calculate the area of specimen to be examined in order to achieve the selected analytical sensitivity. Caiculate the maximum number of grid openings to be examined using the following equation: Af k A9VS where is the number of grid openings to be ex- amined, rounded upwards to the next highest integer; L o ISO Af is the area, in square millimetres, of sam- ple filter; A9 is the area, in square millimetres, of TEM specimen grid opening; V is the volume of air sampled, in litres; S is the required analytical sensitivity, ex- pressed in number of structures per litre. 9.6.5 General procedure for structure counting and size analysis Use at least two specimen grids prepared from the fiiter in the structure count. Select at random several grid openings from each grid, and combine the data in the calculation of the results. Use a form similar to that shown in figure 4 to record the data. Insert the first specimen grid into the TEM. NOTE 10 In order to facilitate quality assurance mea- surements which require re-examination of the same grid opening by different microscopists, the grid should be in- serted into the specimen holder in a standard orientation with the grid bars parallel and perpendicular to the axis of the specimen holder. This will provide scan directions par- allel to the edges of the grid opening. It should be ensured that all microscopists begin scanning at the same starting point on the grid opening, and that they use similar scan patterns. This procedure permits rapid relocation of fibrous structures for further examination if necessary. Select a typicai grid opening and set the screen mag- nification to the calibrated value (approximately x 20 000). Adjust the sample height untii the features in the centre of the TEM viewing screen are at the eucentric point. Set the goniometer tiit angle to zero. In column 1 of the data recording form, record the number or letter used to identify the grid. In column 2, record the identification of the particular grid open- ing. Position the specimen so that the grid opening is positioned with one corner visible on the screen. Move the image by adjustment of only one tra�slation control, carefully examining the sample for fibres, until the opposite side of the grid opening is encountered. Move the image by a predetermined distance less than one screen diameter, using the other translation control, and scan the image in the reverse direction. Continue the procedure in tnis manner until the entire grid opening has been inspected in a pattern similar to that shown in figure 5. When a fibrous structure is detected, assign a sequential number to the primary structure in column 3, perform the identification pro- cedures required as detailed in annex E, and enter the appropriate compositional classification on the struc- ture counting form in column 5. Assign a ISO 10312:1995(E1 morphological classification to the structure according to the procedures specified in annex D, and record this in column 6. Measure on the TEM viewing screen the length and width of the image of the primary structure, in millimetres, and record these mea- surements in columns 7 and 8. For a disperse ciuster or matrix, assign a compositional classification and a morphological classification to each structure compo- �ent, measure ihe length and width, and enter the data in columns 4 to 8. Use column 4 of the data re- cording form to tabulate the sequential number of total structures taking into account structure compo- nents. if non-asbestos fibres are observed, note their presence and type, if known. After a fibrous structure has been examined and measured, relocate the orig- inal field of view accurately before continuing scan- ning of the specimen. Failure to do this may cause structures to be overlooked or counted twice. Con- tinue the examination until the compietion of the grid opening on which the 100th asbestos structure has been recorded, or until the number of grid openings required to achieve the specified analytical sensitivity, calculated according to 9.6.4, have been examined whichever occurs first. The data shall be drawn ap- proximately equally from a minimum of two grids. Regardless of the value calculated according to 9.6.4, fibrous structures on a minimum of four openings shall be counted. 9.6.6 Measurement of concentration for asbestos fibres and bundles longer than 5 µm Consider improving the statistical validity for meas- urement of asbestos fibres and bund(es longer than 5 µm by additional examination at a lower magnifica- tion, taking account only of the longer fibres and bundles. Perform this extended examination for fibres and bundles longer than 5 µm in accordance with the procedures specified in annex E. Use a magnification of approximately x 10 000 for counting all asbestos fibres and bundles longer than 5 µm, or approximately x 5 000 if only fibres and bundles within the diameter range 0,2 µm to 3,0 µm are to be counted. Continue the count until completion of the grid opening on which 100 fibres and bundles have been recorded, or until a sufficient area of the specimen has been ex- amined to achieve the desired analytical sensitivity. Only those structures which are identified as, or are suspected to be, either chrysotile or one of the amphibole minerals will be reported in either the original or the extended TEM examination. Other ma- terials, such as gypsum, ceilulose fibres, and filter artifacts such as undissolved filter strands, will not be inciuded in the fibre count. This restriction is intended to ensure that the best statisticai validity is obtained for the materials of interest. 15 ISO 10392:1995 jE) TEM asbestos structure count (page of ) Report number : ................................. ............... Sample number : .................................................... Filename : .............................................................. Sample description : .............................................. ................................................................................. ......................... ........................................................ Preparation date : .................. By: ........................ Analysis date : ....................... By: ........................ Computer entry date: ........... By : ........................ � ISO Air volume : ...................................................... litres Sample filter area : ............................................ mmZ Magnification : .................. Grid opening dimension : .................................... µm Level of analysis (C) : .................................................... (A) : ....................................... Grid Number of Grid opening structures Class Type of Length Width Comments structure primary totai mm mm Figure 4— Example of structure counting form 16 S First pass � TEM field of view ISO 10312:1995(E) �- Gtid opening Figure 5— Example of scanning procedure for TEM specimen examination 9.7 Blank and quality control determinations Before air sampies are collected, a minimum of two unused filters from each filter lot of 100 filters shall be analysed to determine the mean asbestos struc- ture count. If the mean count for all types of asbestos structures is found to be more than 10 structures( mmZ, or if the mean fibre count for asbestos fibres and bundles longer than 5 µm is more than 0,1 fibre� mm2, reject the filter lot. To ensure that contamination by extraneous asbestos fibres during specimen preparation is insignificant compared with the results reported on samples, es- tablish a continuous programme of blank mea- surements. At least one field blank shail be processed along with each batch of sampies. In addition, at least one unused filter shall be included with every group of samples prepared on one microscope slide. Initially, and also at intervals afterwards, ensure that samples of known asbestos concentrations can be analysed satisfactorily. Since there is a subjective component in the structure counting procedure, it is necessary that recounts of some specimens be made by different microscopists, in order to minimize the subjective effects. Such recounts provide a means of maintaining comparability between counts made by different microscopists. Variability between and within microscopists and between laboratories shall be characterized. These quality assurance measurements shall constitute approximately 10 % of the analyses. Repeat results should not differ at the 5% signif- icance level. 17 ISO 10312:1995(E) 9.8 Calculation of results Calculate the results using the procedures detailed in annex F. Prior to the TEM examination of the speci- mens, the level of analysis was specified. Before the results are calculated, the compositional and morphological classifications to be included in the re- sult shall be specified. The chi-squared uniformity test shall be conducted using the number of primary asbestos structures found on each grid opening, prior to the application of the cluster and matrix counting criteria. The concentration result shall be calculated using the numbers of asbestos structures reported after the application of the cluster and matrix counting criteria. 10 Performance characteristics 10.1 General It is important to use this analyticai method in con- junction with a continuous quality control programme. The quality control programme should include use of standard samples, blank sampies, and both interlabo- ratory and intralaboratory analyses. 10.2 Interferences and limitations of fibre identification Unequivocal identification of every chrysotile fibre is not possible, due to both instrumental limitations and the nature of some of the fibres. The requirement for a calibrated ED pattern eliminates the possibility of an incorrect identification of the fibre selected. However, there is a possibility of misidentification of fibres for which both the morphologies and the ED patterns are reported on the basis of visual inspection only. The only significant possibilities of misidentification occur with halloysite, vermiculite scrolis or palygorskite, ali of which can be discriminated from chrysotile by the use of EDXA and by observation of the 0,73 nm (002) reflection of chrysotile in the ED pattern. As in the case of chrysotile fibres, complete identifi- cation of every amphibole fibre is not possible due to instrumental limitations and the nature of some of the fibres. Moreover, complete identification of every amphibole fibre is not practical due to the limitations of both time and cost. Particles of a number of other minerais with compositions similar to those of some amphiboles could be erroneously classified as amphibole when the classification criteria do not in- clude zone-axis ED techniques. However, the re- quirement for quantitative EDXA measurements on all fibr�s as support for the random orientation ED technique makes misidentification very unlikely, par- 18 � ISO ticularly when other similar fibres in the same sample have been identified as amphibole by zone-axis methods. The possibility of misidentification is further reduced with increasing aspect ratio, since it is rare for the minerals with which amphibole may be con- fused to display an asbestiform habit. 10.3 Precision and accuracy (see ISO Standard Handbook No. 3) 10.3.1 Precision The analytical precision that can be obtained is de- pendent upon the number of structures counted, and also on the uniformity of the particulate deposit on the original filter. Assuming that the structures are ran- domly deposited on the fiiter, if 100 structures are counted and the loading is at least 3,5 structures/grid opening, computer modeliing of the counting proce- dure shows that a coefficient of variation of about 10 % can be expected. As the number of structures counted decreases, the precision will also decrease approximately as �N , where N is the number of structures counted. In practice, particulate deposits obtained by filtration of ambient air samples are rarely ideally distributed, and it is found that the precision is correspondingly reduced. Degradation of precision is a consequence of several factors, such as: a) non-uniformity of the filtered particulate deposit; b) distorsion of the fibre distribution by application of the structure counting criteria; c) variation between microscopists in their interpre- tation of the fibrous structures; d) variation between microscopists in their ability to detect and identify fibres. The 95 % confidence interval about the rnean for a single structure concentration measurement using this analyticai method should be a�proximately ± 25 % when 100 structures are counted over 10 grid openings. 10.3.2 Accuracy There is no independent method available to deter- mine the accuracy. NOTE 11 It has been demonstrated that, after polycarbonate membrane filters have been coated with carbon, particulate material is transferred to the TEM specimens without measurable losses. However, if the fil- ters are heavily loaded by particulate material, some of this may be lost before they are coated with carbon. Good comparabiliry between the capillary-pore polycarbonate pro- E o ISO cedure and the cellulose ester filter procedure has been demonstrated for laboratory�enerated aerosols of chrysotile asbestos. 10.3.3 I�terlaboratory and intralaboratory analyses Interlaboratory and intralaboratory analyses are re- quired in order to monitor systematic errors that may develop among microscopists when using this method. These analyses should be designed to test both the overall method and the performance of indi- vidual microscopists. Repeating preparation of TEM grids from different sectors of a filter, followed by examination of the grids by a different microscopist, is a test for the reproducibility of the whole method. However, non-uniformity of the particulate deposit on the fiiter may lead to differences which are not related to the performance of the microscopists. Verified fibre counting (counting of asbestos structures on the same grid opening of a TEM grid by two or more op- erators, followed by resolution of any discrepancies) may be used both as a training aid and to determine the performance of different microscopists. The use of indexed TEM grids as described in 7.4.1 and 7.4.2 is recommended in order to facilitate relocation of specific grid openings. 10.4 Limit of detection The limit of detection of the method can be varied by ` choice of the area of the collection filter, the volume of air sarripled and the area of the specimen examined in the TEM. It is also a function of the background of asbestos structures on unused filters. A limit of de- tection shall be quoted for each sample analysis. _ NOTE 12 In practice, the ►owest limit of detection is fre- , quently determined by the total suspended particulate con- centration, since each particle on the filter must be separated from adjacent ones by a distance large enough for the particle to be identified without interference. Particulate loadings on sampling filters greater than 25 µg�cm2 usually preclude preparation of TEM specimens by the direct methods. If the analysis is to be performed with an acceptable expenditure of time, the area of the specimen examined in the TEM for structures of ali sizes is limited in most cases to between 10 and 20 grid openings. In typical ambient or building atmospheres, it has been found that an analytical sensitiviry of 1 structure�l can be achieved. In some circumstances, where the atmosphere is exceptionaily clean, this can be reduced to 0,1 structure/I or �ower. For fibres and bundles longer than 5 µm, the re- duced magnifications specified permit larger areas of the TEM specimens to be examined with an acceptable ex- penditure of time, resulting in proportionately lower limits of detection. If no structures are found in the analysis, the , upper 95 % confidence limit can be quoted as the upper ISO 10312:1995(Ei boundary of the concentration, corresponding to 2,99 time� the analytical sensitiviry if a Poisson distribution of struc• tures on the filter is assumed. This 95 °/a confidence limil for 0 structures counted is taken as the detection limit. Since there is sometimes contamination of unused sampies filters by asbestos structures, this should also be taken into account in the discussion of limits of detection. 11 Test report The test report shall include at least the foliowing in- formation: a) reference to this International Standard; b) identification of the sample; c) the date and time of sampling, and all necessary sampling data; d) the date of the analysis; e) the identity of the analyst; f) any procedure used that is not specified in this International Standard or regarded as optional; g? a complete listing of the structure counting data (the following data shouid be included: grid open- ing number, structure number, identification cate- gory, structure type, length and width of the structure in micrometres, and any comments concerning the structure); h) a statement of the minimum acceptable identifi- cation category and the maximum identification category attempted (refer to tables D.1 and D.21; i) a statement specifying which identification and structure categories have been used to calculate the concentration values; j) separate concentration values for chrysotile and amphibole structures, expressed in number of asbestos structures per litre; k) the 95 % confidence interval limits for the con- centration values, expressed in number of asbestos structures per litre; I) the analytical sensitivity, expressed in number of asbestos structures per litre; m) the limit of detection, expressed in number of asbestos structures per litre; n) compositional data for the principal varieties of amphibole, if present; 19 IS0 10312:1995�E) 0) items g) to m) for asbestos fibres and bundles longer than 5 µm; �. � � p) items g) to m) for PCM equivalent asbestos fibres and bundles. An exampie of a suitable format for the structure i counting data is shown in figures 6 and 7. Sample analysis information (page 1) Laboratory name Report number Sample: 456 Queen Street Ashby de la Zouch Exterior sample 1991-09-09 Date Air volume: Area of collection fiiter: 2 150,0 litres Levei of analysis (chrysotile}: 385,0 mm2 Level of analysis (amphibole): CD or CMQ Magnification used for fibre counting: ADQ x 20 500 Aspect ratio for fibre definition: 5/1 Mean dimension of grid openings: 95,4 µm initials of analyst: �MW Number of grid openings examined: 10 Analytical sensitivity: 1,968 structuresii Number of primary asbestos structures: � 3 Number of asbestos structures counted: 26 Number of asbestos structures > 5 µm : � Number of asbestos fibres and bundles > 5 µm : 10 Number of PCM equivalent asbestos structures: 3 Number of PCM equivalent asbestos fibres: 5 Figure 6— Example of format for reporting sample and preparation data 20 o ISO Sample analysis information (pages 2 and following) Laboratoriy name Report number Sample: 456 Queen Street Ashby de la Zouch Exterior sample 1991-09-09 TEM asbestos structure count - Raw data Date ISO 70312:1995(Ej Numbe� of Grid Grid �ructures �dentifi- Structure Length Width Comments opening cation>> type primary total µm µm A F4-4 1 1 CD F 1,7 0,045 2 2 CMQ B 2,6 0,09 3 3 ADQ F 4,0 0,15 Crocidolite E3-6 4 4 CD MC+O 3,5 1,3 E5-1 5 CD MD43 7,5 5,0 5 CD MB 7,7 0,30 6 CMQ MF 5,6 0,045 7 CD MB 5,1 0,30 8 CD MF 1,7 0,045 B F4-1 6 CD CD+O 6,5 3,0 9 CD CB 3,5 0,15 10 CD CF 3,5 0,045 11 CMQ CR+O 2,6 1,9 G5-1 7 CD CD31 6,1 3,2 12 CD CB 5,6 0,3 13 CMQ CF 4,0 0,045 14 CMQ CB 3,2 0,090 E4-4 8 15 CD B 1,5 0,23 9 16 AD F 8,7 0,15 C G4-4 10 CMQ CD42 25 5,6 17 CMQ CB 15 0,15 18 CMQ CF 9,4 0,045 19 ADQ CF 3,6 0,30 Tremolite 20 CM CF 4,2 0,045 E4-4 No tibres E5-6 11 ADQ CD+3 9,4 2,5 21 ADQ CF 7,1 0,30 Amosite 22 ADQ CF 6,2 0,10 Crocidolite 23 CM CB 5,1 0,2 24 CM CR+O 3,3 1,8 F4-1 12 25 CMQ MC10 3,7 2,1 13 26 CD CC+O 7,4 0,5 1) Identification codes listed in tables D.1 and D.2. Figure 7- Example of format for reporti�g structure counting data 21 ISO 10312:9995(E) � ISO Annex A (normative) Determination of operating conditions for plasma asher A.1 Generai During the preparation of TEM specimens from an MEC or cellulose nitrate filter, the spongy structure of the filter is collapsed into a thinner film of polymer by the action of a solvent. Some of the particles on the surface of the original filter become completely buried in the polymer, and the specimen preparation procedure incorporates a plasma etching step to oxidize the surface layer of the polymer. Particles buried by the filter coilapsing step are then exposed so that they can become subsequently affixed to the evaporated carbon fiim without altering their position on the original filter. The amount of etching is criticai, and individual ashers vary in performance. Therefore, the piasma asher (7.3.4) shafl be calibrated to give a known amount of etching of the surface of the col- lapsed filter. This is carried out by adjusting the radio-frequency power output and the oxygen flow- rate, and measuring the time taken to completely oxidize an uncollapsed cellulose ester filter with 25 mm diameter of the same type and pore size as those used in the analysis. 22 A.2 Procedure Place an unused cellulose ester fiiter, with 25 mm di- ameter, of the same type as that being used, in the centre of a glass microscope slide. Position the slide approximately in the centre of the asher chamber. Close the chamber and evacuate to a pressure of ap- proximately 40 Pa, while admitting oxygen to the chamber at a rate of 8 miJmin to 20 ml/min. Adjust the tuning of the system so that the intensity of the plasma in maximized. Measure the time required for complete oxidation of the filter. Determine operating parameters which resuit in complete oxydation of the filter in a period of approximately 15 min. For etching of coliapsed filters, these operating parameters shail be used for a period of 8 min. NOTE 13 Piasma oxidation at high radio-frequency pow- ers will cause the filter to shrink and cur.l, foilowed by sud- den violent ignition. At lower powers, the filter wiil remain in position and wi�i slowly become thinner until it is nearly transparent. It is recommended that a radio-frequency power be used such that violent ignition does not occur. When multiple filters are etched, the rate of etching is re- duced, and the system should be calibrated accordingly. _ o ISO ISO 10312:1995(E► a Annex B (normative) Calibration procedures B.1 Calibration of the TEM B.1.1 Calibration of TEM screen magnification The electron microscope should be aligned according to the specifications of the manufacturer. initially, and at regular intervals, calibrate the magnifications used for the analysis using a diffraction grating replica (7.3.11). Adjust the specimen height to the eucentric position before carrying out the calibration. Measure the distance on the fluorescent viewing screen occu- pied by a convenient number of repeat distances of the grating image, and calculate the magnification. Always repeat the calibration after any instrumental maintenance or change of operating conditions. The magnification of the image on the viewing screen is not the same as that obtained on photographic plates or film. The ratio between these is a constant value for the particular model of TEM. 6.1.2 Calibration of ED camera constant Calibrate the camera constant of the TEM when used in ED mode. Use a specimen g�id supporting a carbon film on which a thin film of gold has been evaporated or sputtered. Form an image of the gold film with the specimen adjusted to the eucentric position and se- lect ED conditions. Adjust the objective lens current to optimize the pattern obtained, and measure the di- ameters of the innermost two rings either on the flu- orescent viewing screen or on a recorded image. Calculate the radius-based camera constant, aL, for both the fluorescent screen and the photographic plate or film, using the following equation: u _ aD 2,0 h2 + k2 + l2 where � is the wavelength, in nanometres, of the incident electrons; G is the camera length, in millimetres; a is the unit cell dimension of gold, in nanometres (= 0,407 86 nm1; D is the diameter, in millimetres, of the (hk!) diffraction ring. Using goid as the calibration material, the radius- based camera constant is given by aL = 0,117 74D mm•nm (smallest ring) �L = 0,101 97D mm•nm (second ring) B.2 Calibration of the EDXA system Energy calibration of the EDXA system for a low en- ergy and high energy peak shall be performed regu- larly. Calibration of the intensity scale of the EDXA system permits quantitative composition data, at an accuracy of about 10 % of the elemental concen- tration, to be obtained from EDXA spectra of refer- ence silicate minerals involving the elements Na, Mg, AI, Si, K, Ca, Mn and Fe, and applicable certified reference materials. If quantitative determinations ai-e required for minerals containing other elements, ref- erence standards other than those referred to below will be required. Weli-characterized mineral standards permit calibration of any TEM-EDXA combination which meets the instrumental specifications of 7.3.1 and 7.3.2, so that EDXA data from different instru- ments can be compared. Reference minerals are re- quired for the calibration; the criteria for selection being that they should be silicate minerals with ma- trices as close as possible to those of the amphiboles or serpentine, and that small individual fragments of the minerals are homogeneous in composition within a few percent. Determine the compositions of these standards by electron microprobe analysis or chemicals methods. Crush fragments of the same selected mineral stan- dards and prepare filters by dispersal of the crushed material in water and immediate filtration of the sus- pensions. Prepare TEM specimens from these�filters according to the procedures specified in ciause 9. These TEM specimens can then be used to calibrate any TEM-EDXA system so that comparable composi- 23 130 10312:1995(E) tional results can be obtained from different instru- ments. NOTES 14 The microprobe analysis of the mineral standards are carried out by conventional techniques which can be found in annex J. The mineral is first embedded in a mount of poly(methyl methacrylate) or epoxy resin. The mount is then ground and polished to achieve a flat, polished surface of the mineral fragment. This surface is then analysed, using suitable reference standards, preferably oxide standards of the individual elements wherever these are available. It is necessary to take into account the water concentration in the minerals, which in the case of chrysotile amounts to 13 % by mass. This water content may vary due to losses in the vacuum system. 15 Aqueous suspensions of mineral standards should be filtered immediately after preparation, since alkali and alkali earth metals may be partially leached from minerals con- taining these elements. Express the results of the electron microprobe ana- lyses as atomic or mass percentage ratios relative to silicon. X-ray peak ratios of the same elements rela- tive to silicon, obtained from the EDXA system, can then be used to calculate the relationship between peak area ratio and atomic or mass percentage ratio. The technique was described by Cliff and Lorimer (see annex J, reference [8)). The X-rays generated in a thin specimen by an inci- dent electron beam have a low probability of interact- ing with the specimen. Thus, mass absorption and fluorescence effects are negligible. In a silicate min- eral specimen containing element i, the following equation can be used to perform quantitative analyses in the TEM: C• A• � — k� X , Cs� As where C; is the concentration or atomic percentage of element i; CS; is the concentration or atomic percentage of silicon; 24 � ISO A; is the elementaf integrated peak area for element i; AS; is the elemental integrated peak area for silicon; k; is the k-ratio for element i relative to sili- con. For a particular instrumental configuration and a par- ticular particle size, the value of k; is constant. To incorporate correction for the particle size effect on peak area ratios (see annex J, references [35] and [36], extend the Cliff and Lorimer technique by ob- taining separate values of the constant k; for different ranges of fibre diameter. It is recommended that 20 EDXA measurements be made for each range of fibre diameters. Suitable ranges of fibre diamete� are: < 0,25 µm; 0,25 µm to 0,5 µm; 0,5 µm to 1,0 µm; > 1,0 µm. Insert the TEM grid into the transmission electron microscope, obtain an image at the calibrated higher magnification of about x 20 000, and adjust the spec- imen height to the eucentric point. If the X-ray detec- tor is a side-entry variety, tilt the specimen towards the X-ray detector. Select an isolated fibre or particle less than 0,5 µm in width, and accumulate an EDXA spectrum using an electron probe of suitable diam- eter. When a well-defined spectrum has been ob- tained, perform a background subtraction and calculate the background-corrected peak areas for each element listed, using energy windows centred on the peaks. Calcu�ate the ratio of the peak area for each specified element relative to the peak area for silicon. All background-subtracted peak areas used for calibration shall exceed 400 counts. Repeat this procedure for 20 particles of each mineral standard. Reject analyses of any obviousiy foreign particles. Calculate the arithmetic mean concentration to peak area ratio, k; (k-ratio), for each specified ele- ment of each mineral standard and for each of the fi- bre diameter ranges. Periodic routine checks shall be carried out to ensure that there has been no degra- dation of the detector performance. These k-ratios are used to calculate the elem�ntal concentrations of un- known fibres, using the Cliff and l.orimer relationship. . o ISO (SO 10312:1995(E) Annex C (normative) Structure counting criteria C.1 General In addition to isolated fibres, other assemblages of particles and fibres frequently occur in air samples. Groupings of asbestos fibres and particles, referred to as "asbestos structures", are defined as fibre bun- dles, clusters and matrices. The numerical resu�t of a TEM examination depends largely on whether the analyst assigns such an assemblage of fibres as a ; single entity, or as the estimated number of individual fibres which form the assemblage. It is therefore im- portant that a logical system of counting criteria be defined, so that the interpretation of these complex structures is the same for ali analysts, and so that the numerical result is meaningful. Imposition of specific structure-counting criteria generally requires that some interpretation, partially based on uncertain in- formation on health effects, be made of each asbestos structure found. It is not the intention of this International Standard to make any interpretations based on health effects, and it is intended that a clear separation shall be made between recording of struc- . ture counting data, and later interpretation of those data. The system of coding specified in this Interna- tionai Standard permits a clear morphological de- scription of the structures to be recorded in a concise manner suitable for later interpretation, if necessary, by a range of different criteria, without the necessity for re-examination of the specimens. In particular, the coding system is designed to permit the dimensions of each complex fibrous structure, and also whether these structures contain fibres longer than 5 µm, to ' be recorded. This approach permits later evaluations of the data to include considerations of particle respirability and comparisons with historical indices of asbestos exposure. Exampies of the various types of morphological structure, and the manner in which these shall be recorded, are shown in figure C.1. C.2 Structure definitions and treatment Each fibrous structure that is a separate entity shall be designated as a primary structure. Each primary structure shall be designated as a fibre, bundle, clus- ter or matrix. C.2.1 Fibre Any particle with parallel or stepped sides, of mini- mum length 0,5 µm, and with an aspect ratio of 5/1 or greater, shall be defined as a fibre. For chrysotile asbestos, the single fibril shall be defined as a fibre. A fibre with stepped sides shall be assigned a width equai to the average of the minimum and maximum widths. This average shall be used as the width in determination of the aspect ratio. C.2.2 Bundle A grouping composed of apparently attached parallei fibres shall be defined as a bundle, with a width equal to an estimate of the mean bundle width, and a length equal to the maximum length of the structure. The overall aspect ratio of the bundle may have any value, provided that it contains individual constituent fibres with aspect ratios equal to or greater than 5/1. Bun- dles may exhibit diverging fibres at one or both ends. C.2.3 Cluster An aggregate of two or more randomly oriented fi- bres, with or without bundles, shall be defined as a cluster. Clusters occur as two varieties. C.2.3.1 disperse cluster (type D): Disperse and open network, in which at least one of the individual fibres or bundles can be separately identified and its dimensions measured; C.2.3.2 compact cluster (type C): Complex and tightly bound network, in which one or both ends of each individual fibre or bundle is (are) obscured, such that the dimensions of individual fibres and bundles cannot be unambiguously determined. In practice, clusters can occur in which the character- istics of both types of cluster occur in the same structure. Where this occurs, the structure should be defined as a disperse cluster, and then a logical pro- cedure should be followed by recording structure components according to the counting criteria. The . procedure for treatment of ciusters is illustrated by examples in figure C.2. 25 ISO 10312:1995(E) 26 a) Disperse cluster (type D) c) Disperse matrix (type D) �. � Fibres Bundles , •, �� � ..� ,;�� �� ��. i�; :, � ' /'' : . �.. b) Compact cluster (type C� d► Compact metrix (type C) Figure C.1 — Fundamental morphological structure types � o ISO L 1 5µm 5µm 5 µm 5µm ISO 10312:1995{E) Count as 1 compact cluster containing more than 9 fi- bres (all fibres shorter than 5 µm) Record as CC+O Count as 1 disperse cluster consisting of 5 fibres, 4 of which are longer than 5 µm Record as CD54, followed by 5 fibres, each recorded as CF Count as 1 disperse cluster consisting of 4 fibres, 2 of which are longer than 5 µm, and 2 cluster residuais, each containing more than 9 fibres Record as CD+2, followed by 4 fibres, each recorded as CF, and 2 cluster residual, each recorded as CR+O Count as 1 disperse cluster consisting of 3 fibres, 2 bundles, 1 of which is longer than 5 µm, and 1 cluster residual containing more than 9 fibres Record as CD+1, followed by 3 fibres, each recorded as CF, 2 bundles, each recorded as CB, and 1 cluster residual recorded as CR+O Figure C.2 — Examples of recording of complex asbestos clusters 27 ISO 1Q312:7995�E) C.2.4 Matrix One or more fibres, or fibre bundles, may be attached to, or partially concealed by, a single particle or group of overlapping nonfibrous particles. This structure shall be defined as a matrix. The TEM image does not discriminate between particles which are attached to fibres, and those which have by chance overlapped in the TEM image. (t is not known, therefore, whether such a structure is actually a complex particle, or whether it has arisen by a simple overlapping of par- ticies and fibres on the filter. Since a matrix structure may invoive more than one fibre, it is important to define in detail how matrices shall be counted. Matrices exhibit different character- istics, and two types can be defined. C.2.4.1 disperse matrix (type D): Structure con- sisting of a particle or linked group of particles, with overlapping or attached fibres or bundles in which at least one of the individual fibres or bundles can be separately identified and its dimensions measured. C.2.4.2 compact matrix (type C): Structure con- sisting of a particie or linked group of particles, in which fibres or bundles can be seen either within the structure or projecting from it, such that'the dimen- sions of individual fibres and bundles cannot be un- ambiguously determined. In practice, matrices can occur in which the charac- teristics of both types of matrix occur in the same structure. Where this occurs, the structure should be assigned as a disperse matrix, and then a logical pro- cedure should be followed by recording structure components according to the counting criteria. Exam- ples of the procedure which shall be followed are shown in figure C.3. C.2.5 Asbestos structure larger than 5 µm Any fibre, bundle, cluster or matrix for which the largest dimension exceeds 5 µm. Asbestos structures larger than 5 µm do not necessarily contain asbestos fibres or bundles longer than 5 µm. 28 � ISO � C.2.6 Asbestos fibre or bundle longer than 5 µm An asbestos fibre of any width, or bundie of such fi- bres, which has a lengtn exceeding 5 µm. C•2.7 PCM equivalent structure , Any fibre, bundle, cluster or matrix with an aspect ra- tio of 3/1 or greater, longer than 5 µm, and which has a diameter between 0,2 µm and 3,0 µm. PCM equiv- alent structures do not necessarily contain fibres or bundles longer than 5 µm, or PCM equivalent fibres. C•2•8 PCM equivalent fibre Any particie with parallel or stepped sides, with an aspect ratio ot 3/1 or greater, longer than 5 µm, and which has a diameter between 0,2 µm and 3,0 µm. For chrysotile, PCM equivalent fibres will always be bundles. C.3 Other structure counting criteria C.3.1 Structures which intersect grid bars A structure which intersects a grid bar shall only be counted on two sides of the grid opening, as illus- trated in figure C.4. Record the dimensions of the structure such that the obscured portions of compo- nents are taken to be equivalent to the unobscured portions, as shown by the broken lines in figure C.4. For example, the length of a fibre intersecting a grid bar is taken to be twice the unobscured length. Structures intersecting either of the other two sides shali, not be included in the count. C.3.2 Fibres which extend outside the field of view During scanning of a grid opening, count fibres which extend outside the field of view systematically, so as to avoid double-counting. In general, a rule should be established so that fibres extending outside the field of view in only two quadrants are counted. The pro- cedure is illustrated by figure C.S. Measure the length of each of these fibre by moving the specimen to lo- cate the other end of the fibre, and then return to the original field of view before continuing to scan the specimen. Fibres without terminations within the field of view shall not be counted. � o ISO I i 5µm ( I 5µm L I 5µm ISO 10312:1995(E) Count as 1 compact matrix, with all fibres shorter than 5 µm Record as MC+O Count as 1 disperse matrix consisting of 1 fibre shorter than 5 µm Fiecord as MD10, followed by 1 fibre recorded as MF Count as 1 disperse matrix consisting of 5 fibres, all longer than 5 µm Record as MD55, followed by 5' fibres, each recorded as MF Count as 1 disperse matrix, consisting if 3 fibres, 1 of which is longer than 5 µm, and 1 matrix residual con- taining 3 fibres Record as MD61, followed by 3 fibres, each recorded as MF, and 1 matrix residuai recorded as MR30 5 µm Figure C.3 — Examples of recording of complex asbestos matrices 29 ISO 10312:1995(E) � • •. Scan direction ; � : • . _ .... Grid opening � ' • �...,,��� Figure C.4 — Example of counting of structures which intersect grid bars Scan direction Count O�IIII�'IiIND '�—TEM field of view Do not count Do not count Grid opening Figure C.5 — Example of counting of fibres which extend outside the field of view 30 � ISO p e , m o ISO ISO 10312:1995(E1 < C.4 Procedure for data recording C.4.1 General The morphological codes specified are designed to facilitate computer data processing, and to allow re- cording of a complete representation of the important features of each asbestos structure. The procedure requires that the microscopist classify each primary fibrous structure into one of the four fundamental categories: fibres, bundles, clusters and matrices. C.4.2 Fibres On the structure counting form, a fibre as defined in C.2.1 shall be recorded by the designation "F". If the fibre is a separately-counted part of a cluster or ma- trix, the fibre shall be recorded by the designation "CF", or "MF", depending on whether it is a compo- nent of a cluster or matrix. C.4.3 Bundles On the structure counting form, a bundle as defined in C.2.2 shaii be recorded by the designation "B". If the bundle is a separately-counted part of a ciuster or matrix, the bundie shall be recorded by the desig- nation "CB", or "MB", depending on whether it is a component of a cluster or matrix. C.4.4 Disperse clusters (type D) On the structure counting form, an isolated cluster of type D as defined in C.2.3 shall be recorded by the designation "CD", foliowed by a two-digit number. The first digit represents the analyst's estimate of the total number of fibres and bundles comprising the structure. The digit shail be from 1 to 9, or designated ' as "+" if there are estimated to be more than 9 component fibres or bundles. The second digit shall � represent, in the same manner, the total number of fibres and bundles longer than 5 µm contained in the structure. The overall dimensions of the cluster, in two perpendicular directions representing the maxi- mum dimensions, shall be recorded. In order of de- creasing length, up to 5 component fibres or bundles shall be separately recorded, using the codes "CF" (cluster fibre) and "CB" (cluster bundle). If, after ac- counting for prominent component fibres and bun- dies, a group of clustered fibres remains, this shall be recorded by the designation "CR" (ciuster residual). If the remaining clustered fibres are present as more than one localized group, it may be necessary to re- cord more than one cluster residual. Do not record more than 5 cluster residuals for any cluster. A cluster residual shall be measured and assigned a two-digit number, derived in the same manner as specified for the overall c(uster. Optionally, if the number of com- ponent fibres and bundies in either the original cluster or the cluster residual is outside the range 1— 9, ad- ditional information concerning the number of com- ponent fibres and bundles may be noted in the "comments" column. C.4.5 Compact clusters (type C) On the structure counting form, an isolated cluster of type C as defined in C.2.3 shall be recorded by the designation "CC", followed by a two-digit number. The two-digit number describing the numbers of component fibres and bundles shall be assigned in the same manner as for clusters of type D. The overall dimensions of the cluster in two perpendicular di- rections shall be recorded in the same manner as for clusters of type D. By definition, the constitutent fi- bres and bundles of compact clusters cannot be sep- arately measured; therefore, no separate tabulation of component fibres or bundles can be made. C.4.6 Disperse matrices (type D) On the structure counting form, an isolated matrix of type D as defined in C.2.4 shall be recorded by the designation "MD", followed by a two-digit number. The two-digit number shall be assigned in the same manner as for clusters of type D. The overall dimen- sions of the matrix in two perpendicular directions shall be recorded in the same manner as for clusters of type D. In order of decreasing length, up to 5 component fibres or bundles shall be separately re- corded, using the codes "MF" (matrix fibre> and "MB" (matrix bundle). If after accounting for promi- nent component fibres and bundles, matrix material containing asbestos fibres remains, this shall be re- corded by the designation "MR" (matrix residual). If the remaining matrix fibres are present as more than one localized group, it may be necessary to record more than one matrix residual. Do nat record more than 5 matrix residuals for any matrix. A matrix re- sidual shall be measured and assigned a two-digit number, derived in the same manner as specified for the overali matrix. Optionally, if the nurnber of com- ponent fibres or bundles in either the original matrix or the matrix residual is outside the range 1— 9, ad- ditional information concerning the number of com- ponent fibres and bundies may be noted in the "comments" column. C.4.7 Compact matrices (type C) On the structure counting form, an isolated matrix of type C as defined in C.2.4 shall be recorded by the 31 ISO 10312:1995(F) designation "MC", followed by a two-digit number. The two-digit number shall be assigned in the same manner as for clusters of type D. The overall dimen- sions of the matrix in two perpendicular directions shall be recorded in the same manner as for clusters of type D. By definition, the constitutent fibres and bundles of compact matrices cannot be separately measured; therefore, no separate tabulation of com- ponent fibres or bundles can be made. C.4.8 Procedure for recording of partially obscured fibres and bundles The proportion of the length of a fibre or bundle that is obscured by other particulates shall be used as the basis for determining whether a fibre or bundle is to be recorded as a separate component or is to be considered as a part of a matrix of type C or part of a matrix residual. If the obscured length could not possibiy be more than one-third of the totai length, the fibre or bundle shall be considered a prominent feature to be separately recorded. The assigned length for each such partially obscured fibre or bundle shall be equal to the visible length plus the maximum possible contribution from the obscured portion. Fi- bres or bundies which appear to cross the matrix, and for which both ends can be located approximately, shall be included in the maximum of 5 and recorded according to the counting criteria as separate fibres or bundles. If the obscured length could be more than one third of the total length, the fibre or bundle shall 32 � ISO '- be considered as a part of a compact matrix of type C or part of a matrix residual. C.5 Special considerations for counting of PCM equivalent structures Use 3/1 as the minimum aspect ratio for counting of PCM equivalent structures. This aspect ratio defi�ition is required in order to achieve comparability of the resuits for this size range of structure with historicai optical measurements, but use of this aspect ratio definition does not significantly affect the ability to interpret the whole fibre size distribution in terms of a minimum 5/1 aspect ratio. Some applications may require that a count tie made of PCM equivalent structures only. The coding system permits discrimi- nation between PCM equivalent structures that con- tain fibres and bundles longer than 5 µm and those that do not. NOTE 16 In general, clusters and matrices will yieid fewer components as the minimum dimensions specified for countabie fibres are increased. Thus, it may be found that a particular structure yields a higher number of com- ponent fibres and bundles in a count for all fibre sizes than it does at a reduced magnification when oniy fibres and bundles longer than 5 µm are being counted. However, the requirement that component fibres and bundles be recorded in decreasing length order ensures that the data are con- sistent for a particular structure, regardless of the size cat- egory of fibres being counted and the magnification in use. � o ISO Annex D (normative) Fibre identification procedure D.1 General The criteria used for identification of asbestos fibres may be selected depending on the intended use of the measurements. In some circumstances, there can be a requirement that fibres shali be unequivocaliy identified as a specific mineral species. In other cir- cumstances, there can be sufficient knowledge about the sample, so that rigorous identification of each fi- bre need not be carried out. The time required to perform the analysis, and therefore the cost of analy- sis, can vary widely depending on the identification criteria considered which are to be sufficiently defini- tive. The combination of criteria considered definitive for identif�cation of fibres in a particular analysis shall be specified before the analysis is made, and this combination of criteria shall be referred to as the "level" of analysis. Various factors related to instru- mentai limitations and the character of the sample may prevent satisfaction of all of the specified fibre identification criteria for a particular fibre. Therefore, a record shall be made of the identification criteria which were satisfied for each suspected asbestos fi- bre included in the analysis. For example, if both ED and EDXA were specified to be attempted for defini- tive identification of each fibre, fibres with chrysotile morphology which, for some reason, do not give an ED pattern but which do yield an EDXA spectrum corresponding to chrysotile, are categorized in a way which conveys the level of confidence to be placed in the identification. D.2 ED and EDXA techniques D.2.1 General Initially, fibres are classified into two categories on the basis of morphology: those fibres with tubular morphology, and those fibres without tubular morphology. Further analysis of each fibre is con- ducted using ED and EDXA methods. The following procedures should be used when fibres are examined by ED and EDXA. The crystal structures of some mineral fibres, such as chrysotile, are easily damaged by the high current densities required for EDXA examination. Therefore, ISO 10312:1995(E) investigation of these sensitive fibres by ED should be completed before attempts are made to obtain EDXA spectra from the fibres. When more stable fi- bres, such as the amphiboles, are examined, EDXA and ED may be used in either order. D.2.2 ED techniques The ED technique can be either qualitative or quanti- tative. Qualitative ED consists of visual examination, without detailed measurement, of the general char- acteristics of the ED pattern obtained on the TEM viewing screen from a randomly oriented fibre. ED patterns obtained from fibres with cylindrical symme- try, such as chrysotile, do not change when the fibres are tilted about their axes, and patterns from randomly oriented fibres of these minerals can be interpreted quantitatively. For fibres which do not have cylindrical symmetry, oniy those ED patterns obtained when the fibre is oriented with a principal crystallographic axis closely parallel with the incident electron beam direc- tion can be interpreted quantitatively. This type of ED pattern shall be referred to as a"zone-axis ED pattern". In order to interpret a zone-axis ED pattern quantitatively, it shail be recorded photographicaily and its consistency with known mineral structures shall be checked. A computer program may be used to compare measurements of the zone-axis ED pat- tern with corresponding data calculated from known mineral structures. The zone-axis ED pattern obtained by examination of a fibre in a particular orientation can be insufficiently specific to permit unequivocal iden- tification of the mineral fibre, but is is often possibie to tilt the fibre to another angle and to record a dif- ferent ED pattern corresponding to another zone-axis. The angle between the two zone-axes can also be checked for consistency with the structure of a sus- pected mineral. For visual examination of the ED pattern, the camera length of the TEM should be set to a low value of approximately 250 mm and the ED pattern should then be viewed through the binoculars. This proce- dure minimizes the possibie degradation of the fibre by the electron irradiation. However, the pattern is distorted by the tilt angle of the viewing screen. A camera length of at (east 2 m should be used when 33 ISO 10312:1995(E) the ED pattern is recorded, if accurate measurement of the pattern is to be possible. It is necessary that, when obtaining an ED pattern to be evaluated visually or to be recorded, the sample height shall be properly adjusted to the eucentric point and the image shall be focussed in the plane of the selected area aperture. If this is not done, there may be some components of the ED pattern which do not originate from the selected area. In general, it will be necessary to use the smallest available EO aperture. For accurate measurements of the ED pattern, an internal calibration standard shall be used. A thin coating of goid, or another suitable calibration mate- rial, shall be applied to. the underside of the TEM specimen. This coating may be applied either by vac- uum evaporation or, more conveniently, by sputtering. The polycrystalline gold film yields diffraction rings on every ED pattern and these rings provide the required calibration information. To form an ED pattern, move the image of the fibre to the centre of the viewing screen, adjust the height of the specimen to the eucentric position, and insert a suitable selected area aperture into the electron beam so that the fibre, or a portion of it, occupies a large proportion of the illuminated area. The size of the aperture and the portion of the fibre shall be such that particies other than the one to be examined are excluded from the selected area. Observe the ED pattern through the binoculars. During the observa- tion, the objective lens current should be adjusted to the point where the most complete ED pattern is ob- tained. If an incomplete ED pattern is stili obtained, move the particle around within the selected area to attempt to optimize the ED pattern, or to eliminate possible interferences from neighbouring particles. If a zone-axis ED analysis is to be attempted on the fibre, the sample sha�l be mounted in the appropriate holder. The most convenient hoider allows complete rotation of the specimen grid and tilting of the grid about a single axis. Rotate the sample until the fibre image indicates that the fibre is oriented with its length coincident with the tilt axis of the goniometer, and adjust the sample height until the fibre is at the eucentric position. Tilt the fibre until an ED appears which is a symmetrical, two dimensional array of spots. 7he recognition of zone-axis alignment condi- tions requires some experience on the part of the operator. During tilting of the fibre to obtain zone-axis conditions, the manner in which the intensities of the spots vary should be observed. If weak reflections 34 � ISO occur at some points on a matrix of strong reflections, the possibility of twinning or multiple diffraction ex- ists, and some caution should be exercised in the se- lection of diffraction spots for measurement and interpretation. A full discussion of electron diffraction and multiple diffraction can be found in the references by J.A. Gard C>>7 P.6. Hirsch et a1C14] and H.R. Wenck [427 included in annex J. Not all zone-axis patterns which can be obtained are definitive. Only those which have closely spaced reflections corresponding to low indices in at least one direction should be re- corded. Patterns in which all d-spacings are less than about 0,3 nm are not definitive. A useful guideline is that the lowest angle reflections should be within the radius of the first gold diffraction ring f 111), and that patterns with smaller distances between reflections are usually the most definitive. . Five spots, ciosest to the centre spot, along two intersecting lines of the zone-axis pattern shall be se- lected for measurement, as shown in figure D.1. The distances of these spots from the centre spot and the four angles shown provide the required data for anai- ysis. Since the centre spot is usually very overex- posed, it does not provide a well-defined origin for these measurements. The required distances shall therefore be obtained by measuring between pairs of spots symmetrically disposed about the centre spot, preferabiy separated by several repeat distances. The distances shall be measured with a precision of better than 0,3 mm, and the angles to a precision of better than 2,5°. The diameter of the first or second ring of the calibration pattern (111 and 200) shall also be measured with a precision of better than 0,3 mm. Using gold as the calibration materiai, the radius- based camera constant is given by �L = 0,117 74D mm•nm (first ring) �[. = 0,101 97D mm•nm (second ring) D.2.3 EDXA measurements Interpretation of the EDXA spectrum may be either qualitative or quantitative. For qualitative interpretation of a spectrum, the X-ray peaks originating from the elements in the fibre are recorded. For quantitative interpretation, the net peak areas, after background subtraction, are obtained for the X-ray peaks originat- ing from the elements in the fibre. This method pro- vides quantitative interpretation for those minerals which contain silicon. " � . o ISO , ISO 10312:1995(E) � � Spot � � Spo • • Spot 5 � Spot 2 Spot 1 � 1 Figure D.1 — Example of ineasurement of zone-axis SAED patterns To obtain an EDXA spectrum, move the image of the fibre to the centre of the screen and remove the ob- jective aperture. Se�ect an appropriate electron beam diameter and deflect the beam so that it impinges on the fibre. Depending on the instrumentation, it may be necessary to tilt the specimen towards the X-ray detector and, in some instruments, to use the Scan- ning Transmission Electron Microscopy (STEM) mode of operation. The time for acquisition of a suitable spectrum varies with the fibre diameter, and also with instrumental factors. For quantitative interpretation, spectra should have a statisticaily valid number of counts in each peak. Analyses of small diameter fibres which contain sodium are the most critical, since it is in the low en- ergy range that the X-ray detector is least se�sitive. Consequently, it is necessary to acquire a spectrum for a period that is sufficiently long for the sodium to be detected in such fibres. It has been found that satisfactory quantitative an analyses can be obtained if acquisition is continued until the background sub- tracted silicon Ka peak integral exceeds 10 000 counts. The spectrum should then be manipulated to subtract the background and to obtain the net areas of the elemental peaks. After quantitative EDXA classification of some fibres by computer analysis of the net peak areas, it may be possible to classify further fibres in the same sample on the basis of comparison of spectra at the intrument. Frequently, visua� comparisons can be made after somewhat shorter acquisition times. D.3 Interpretation of fibre analysis data D.3.1 Chrysotile The morphological structure of chrysotile is charac- teristic, and with experience, can be recognized read- ily. However, a few holder minerals have a similar appearance, and morphological observation by itself is inadequate for most samples. The ED pattern ob- tained from chrysotile is quite specific for this minerai if the specified characteristics of the pattern corre- spond to those frorn reference chrysotile. However, depending on the past history of the fibre, and on a number of other factors, the crystal structure of a particular fibre may be damaged, and it may not yield and ED pattern. In this case, the EDXA spectrum may be the only data available to supplement the morphological observations. D.3.2 Amphiboles Since the fibre identification procedure for asbestos fibres other than chrysotile can be involved and time- consuming, computer programmes, such as that de- veloped by B.L. Rhoades (see annex J, reference 35 ISO 1 Q312:1995(E) [32]), are recommended for interpretation of zone- axis ED patterns. The published literature contains composition and crystallographic data for all of the fibrous minerals likely to be encountered in TEM analysis of air samples, and the compositional and structural data from the unknown fibre should be compared with the published data. Demonstration that the measurements are consistent with the data for a particular test mineral does not uniquely identify the unknown, since the possibility exists that data from other minerals may aiso be consistent. It is, however, unlikely that a mineral of another structural class could yield data consistent with that from an amphibole fibre identified by quantitative EDXA and two zone-axis ED patterns. Suspected amphibole fibres should be classified ini- tially on the basis of chemical composition. Either qualitative or quantitative EDXA information may be used as the basis for this classification. From the published data on mineral compositions, a list of min- erals which are consistent in composition with that measured for the unknown fibre should be compiled. To proceed further, it is necessary to obtain the first zone-axis ED pattern, according to D.2.2. It is possible to specify a particular zone-axis pattern for identification of amphibole, since a few patterns are often considered to be characteristic. Unfortu- nately, for a fibre with random orientation on a TEM grid, no specimen holder and goniometer currently available will permit convenient and rapid location of two preselected zone-axes. The most practical ap- proach has been adopted, which is to accept those low index patterns which are easily obtained, and then to test their consistency with the structures of the minerals already preselected on the basis of the EDXA data. Even the structures of non-amphibole minerals in this preselected list shall be tested against the zone-axis data obtained for the unknown fibre, since non-amphibole minerals in some orientations may yield similar .patterns consistent with amphibole structures. The zone-axis ED interpretation shall inciude all min- erals previously selected from the mineral data file as being chemically compatible with the EDXA data. This procedure will usually shorten the list of minerals for which solutions have been found. A second set of zone-axis data from another pattern obtained on the 36 � ISO same fibre can then be processed, either as further confirmation of the identification, or to attempt elim- ination of an ambiguity. In addition, the angle meas- ured between the orientations of the two zone-axes can be checked for consistency with the structures of the minerals. Caution should be exercised in ratio- nalizing the inter-zone-axis angle, since if the fibre co�tains c-axis twinning, the two zone-axis ED pat- terns may originate from the separate twin crystals. in practice, the full identification procedure will normally be applied to very few fibres, unless precise identification of all fibres is required for a particular reason. D.4 Fibre classification categories It is not always possible to proceed to a definitive identification of a fibre; this may be due to instru- mental limitations or to the actual nature of the fibre. In many analyses, a definitive identification of each fibre may not actuaily be necessary if there is other knowledge available about the sample, or if the con- centration is below a level of interest. The analytical procedure shall therefore take ir�to account both in- strumentai limitations and varied analytical require- ments. Accordingly, a system for fibre classification is used to permit accurate recording of data. The ciassi- fications are shown in tables D.1 and D.2, and are di- rected towards identification of chrysotile and amphibole respectively. Fibres shali be reported in these categories. The general principle to be followed in this analytical procedure is first to define the most specific fibre classification which is to be attempted, or the "levei" of .analysis to be conducted. Then, for each fibre examined, record the ciassification which is ac- tually achieved. Depending on the intended use of the results, criteria for acceptance of fibres as "identified" can then be estabiished at any time after completion of the analysis. In an unknown sample, chrysotile wiii be regarded as contirmed only if a recorded, calibrated ED pattern from one fibre in the CD categories is obtained, or if measurements of the ED pattern are recorded at the instrument. Amphibole will be regarded as confirmed only by obtaining recorded data which indicates ex- clusively the presence of amphiboles for fibres clas- sified in the AZQ, AZZ or AllQ categories. , � � o ISO � Cetegory TM CM CD CQ CMQ CDQ NAM Category UF AD AX ADX AQ AZ ADQ AZQ AZZ AZZQ NAM ISO 10312:1995(E) Table D.1 — Classification of fibres with tubular morphology Description Tubufar Morphology, not sufficiently characteristic for classification as chrysotile Characteristic Chrysotile Morphology Chrysotile SAED pattern Chrysotile composition by Quantitative EDXA Chrysotile Morphology and composition by Quantitative EDXA Chrysotile SAED pattern and composition by Quantitative EDXA Non-Asbestos Mineral Table D.2 — Classi�cation of fibres without tubular morphology Description Unidentified Fibre Amphibole by random orientation SAED (shows layer pattern of 0,53 nm spacing) Amphibole by qualitative EDXA. Spectrum has elemental components consistent with amphibole Amphibole by random orientation SAED and qualitative EDXA Amphibole by Quantitative EDXA Amphibole by one Zone-axis SAED pattern Amphibole by random orientation SAED and Quantitative EDXA Amphibole by one Zone-axis SAED pattern and Quantitative EDXA Amphibole by two Zone-axis SAED patierns, with consistent interaxial angle Amphibole by two Zone-axis SAED patterns, with consistent interaxial angle, and Quantitative EDXA Non-Asbestos Mineral D.4.1 Procedure for classification of fibres with tubular morphology suspected to be chrysotile Occasionally, fibres are encountered which have tu- bular morphology similar to that of chrysotile, but which cannot be characterized further either by ED or EDXl�. They may be non-crystalline, in which case ED techniques are not useful, or they may be in a position on the grid which does not permit an EDXA spectrum to be obtained. Alternatively, the fibre may be of organic origin, but the morphology and compo- sition may not be sufficiently definitive enough to 6e disregarded. Accordingly, there is a requirement to record each fibre, and to specify how confidently each fibre can be identified. Classification of fibres will meet with various degrees of success. Figure D.2 shows the ciassification procedure to be used for fi- bres which display any tubular morphology. The chart is self explanatory, and every fibre is either rejected as a non-asbestos mineral (NAM), or classified in some way which by some later criterion could still contribute to the chrysotile fibre count. Morphology is the first consideration, and if this is not similar to that usually seen in chrysotile standard samples, designate the initial classification as TM. Regardless of the doubtful morphology, examine the fibre by ED and EDXA methods according to figure D.2. Where the morphology is more definitive, it may be possible to classify the fibre as having chrysotile morphology (CM). 37 ISO 10312:1995�E) FIBRE WITH TUBULAR MORPHOLOGY ( Is fibre morphology characteristic of that displayed by reference chrysotilei NO TM Examine by SAED Pattern not Chrysotile chrysotile pattern Pattern not present or indistinct TM Examine by quantitative EOXA Composition not that Chrysotile of chrysotile composition No spectrum TM YES CM Examine by SAED Chrysotile Pattern not pattern chrysotile Pattern not present or indistinct CM Exami�e by quantitative EOXA � �����N�������� I orcnrysotue No spectrum CM [ Examine by qua�titative EDXA . Composition not that Chrysotile of chrysotite composition No spectrum NAM CD CDQ Figure D.2 — Classification chart for fibre with tubular morphology 38 � � ISO e ISO For classification as CM, the morphological character- istics required are the following: a1 the individuai fibrils should have high aspect ratios exceeding 5/1, and be about 30 nm to 40 nm in diameter; b) the electron scattering power of the fibre at 60 kV to 100 kV accelerating potential should be sufficiently low for the internal structure to be visible; c) there should be some evidence of an internal structure suggesting a tubular appearance similar to that shown by reference UICC chrysotile, which may degrade in the electron beam. Examine every fibre having these morphological char- acteristics by the ED technique, and classify as chrysotile by ED (CD) only those which give diffraction patterns with the precise characteristics shown in figure D.3. The relevant features in this pattern for identification of chrysotile are as follows: a) the (002) refiections should be examined to de- termine that they correspond closely to a spacing of 0,73 nm; b) the layer line repeat distance should correspond to 0,53 nm; c) there shouid be "streaking" of the (110) and (130) reflections. Figure D.3 — Chrysotile SAED pattern ISO 10312:1995(E) Using the millimetre calibrations on the TEM viewing screen, these observations can readily be made at the instrument. If documentary proof of fibre identification is required, record a TEM micrograph of at least one representative fibre, and record its ED pattern on a separate film or plate. This film or piate shall also carry calibration rings from a known polycrystalline sub- stance such as goid. This calibrated pattern is the only documentary proof that the particular fibre is chrysotile, and not some other tubular or scrolled species such as halloysite, palygorskite, talc or vermiculite. The proportion of fibres which can be successfully identified as chrysotile by ED is variable, and to some extent dependent on both the instru- ment and the procedures of the operator. The fibres that fail to yield an identifiable ED pattern will remain in the TM or CM categories unless they are examined by EDXA. In the EDXA analysis of chrysotile there are only two elements which are relevant. For fibre classification, the EDXA analysis shall be quantitative. If the spec- trum displays prominent peaks from magnesium and silicon, with their areas in the appropriate ratio, and with only minor peaks from other elements, classify the fibre as chrysotile by quantitative EDXA, in the categories CQ, CMQ, or CDQ, as appropriate. D.4.2 Procedure for classification of fibres without tubular morphology, suspected to be amphibole Every particle without tubular morphology and which is not obviously of biological origin, with an aspect ratio of 5�1 or greater, and having parallel or stepped sides, shall be considered as a suspected amphibole fibre. Further examination of the fibre by ED and EDXA techniques will meet with a variable degree of success, depending on the nature of the fibre and on a number of instrumental limitations. It wiil not be possible to identify every fibre completely, even if time and cost are of no concern. Moreover, confir- mation of the presence of amphibole can be acnieved only by quantitative interpretation of zone-axis ED patterns, a very time-consuming procedure. Accord- ingiy, for routine samples from unknown sources, this analytical procedure limits the requirement for zone- axis ED work to a minimum of one fibre represen- tative of each compositional class reported. In some samples, it may be necessary to identify more fibres by the zone-axis technique. When analysing samples from well-characterized sources, the cost of identifi- cation by zone-axis methods may not be justified. The 0,53 nm layer spacing of the random orientation ED pattern is not by itself diagnostic for amphibole, However, the presence of c-axis twinning in many fi- 39 ISO 10312:1995(E) bres leads to contributions to the layers in the pat- terns by several individual parallel crystals of different axial orientations. This apparently random positioning of the spots along the layer lines, if also associated with a high fibre aspect ratio, is a characteristic of amphibole asbestos, and thus has some limited diag- nostic value. If a pattern of this type is not obtained, the identity of the fibre is still ambiguous, since the absence of a recognizable pattern may be a conse- quence of an unsuitable orientation relative to the electron beam, or the fibre may be some other min- eral species. Figure D.4 shows the fibre classification chart to be used for suspected amphibole fibres. This chart shows all the classificatibn paths possible in analysis of a suspected amphibole fibre, when examined sys- tematically by ED and EDXA. Two routes are possible, depending on whether an attempt to obtain an EDXA spectrum or a random orientation ED pattern is made first. The normal procedure for analysis of a sample of unknown origin will be to examine the fibre by random orientation ED, qualitative EDXA, quantitative EDXA, and zone-axis ED, in this sequence. The final fibre classification assigned will be defined either by successful analysis at the maximum required level, 40 � ISO `' or by the instrumental limitations. Any instrumental limitations which affect the quality of the results shall be noted. Record the maximum classification achieved for each fibre on the counting sheet in the appropriate column. The various classification catego- ries can then be combined later in any desired way for calculation of the fibre concentration. The complete record of the results obtained when attempting to identify each fibre can also be used to re-assess the data if necessary. In the unknown sample, zone-axis analysis will be re- quired if the presence of amphibole is to be unequivocaliy confirmed. For this level of analysis, at- tempt to raise the classification of every suspected amphibole fibre to the ADQ category by inspection of the random orientation ED pattern and the EDXA spectrum. In addition, examine at least one fibre from each type of suspected amphibole found by zone-axis methods to confirm their identification. In most cases, because information exists about possible sources of asbestos in close proximity to the air sarnpiing lo- cation, some degree of ambiguity of identification can be accepted. Lower levels of analysis can therefore be accepted for these situations. � 0 o ISO ISO 10312:1995(E) FIBRE WITHOUT TUBULAR MORPHOLOGY Ooes fi6re EDXA �peetrum show elemants Exemine by r�ndom wn�istent with amphiholeT orie�t�tion SAED VES NO P�nern not present L.�yar p�ttern whh NAM or indiatind 0,53 nm apxin0 No speclrum Pettem dafinitety � Uf not amphibole rype UF NAM � Doea quenti[ative EDXA give fihre compoaition tontiitent with emphi6oleT Does EDXAapectrum Ooes EUXA spechvm show elements tonaistent show elements cansistent YES NO with emphibolel with emphibole7 NAM NO YES YES NO NAM AX ADx NAM A� No spectrum No spectrum I� Lt zone•exi� SAED pattem con�iatent wi�h emphibole] UF AD YES NO No pattertt An Uniquefy emphibole so�ution Is /st zone•azis SAED �� pattern eon�i�tent with � Does quantitative EOXA Does quentitative EDXA amphibole� Is tst xone-axis SAEO give fibre composilion give fibre composition pettern eoneistent with eonsietent with consi�lent with NO YES amphi6ole) amphibofel amphibo�e7 NAM � YES NO yES NO NO VES No petter� qZ NAM NAM ADn AD No pattern lo tat zone-axis SAED UF Aa N� panern consistent with Are 2nd aone-axis SAED Is tsl tone-axis SAED omphibole7 pettern �nd interexiel atlem consiatent with angle can�ietent with P NO VES amphi6ole7 Are 2nd ione-axia SAED amphibolei pattemandinterexiel NAM YES NO engle conaietent with VES NO amphiba�e) No pettern � •— c Uniquely amphibale �olution No pattern AOn No pattern An Uniquely amphibole solution Are 2nd zona•exi� SAED pettarn end intereziel engle eonai�tenl with emphibolet NO ' YES No pattern �a C Uniquely emphibole solution Azn Uniquely emphibole wlution U�iqualy amphibole w�ution Uniquely emphibole solution Figure D.4 — Classification chart for fibre without tubular morphology 41 ISO 10312:1995(E) Annex E (normative) � � ISO ' Determination of the concentrations of asbestos fibres and bundles longer than 5 µm, and PCM equivalent asbestos fibres In order to provide increased statistical precision and improved analytical sensitivity for those asbestos fi- bres and bundles longer than 5 µm, it may be decided to perform additional fibre counting at a lower magni- fication, taking accouni only into fibtes and bundles within this dimensional range. The result shall be specified as "number of asbestos fibres and bundles longer than 5 µm". For this examination, use a mag- nification of approximately x 10 000, and continue to assign a morphological code to each structure ac- cording to the procedures specified in annex C. Re- cord fibres and bundles only if their lengths exceed 5 µm. Record cluster and matrix components only if their lengths exceed 5 µm. It may also be decided to provide increased statistical precision and improved analytical sensitivity for fibrous structures longer than 5 µm, with diameters between 0,2 µm and 3,0 µm, which have historically been the basis of risk estimation in the occupational environment (PCM equivalent asbestos fibres). Use a magnification of approximately x 5 000 for this ex- tended fibre count. The result shall be specified as "number of PCM equiValent asbestos fibres". Asbestos structures within this dimensional range do not necessarily incorporate asbestos fibres or bundles longer than 5 µm. 42 Continue the extended sample examination until 100 asbestos structures have been counted, or until a sufficient area of the specimen has been examined to achieve the desired analytical sensitivity calculated according to table 1. The grid openings examined shall be divided approximately equally between a minimum of two specimen grids. � NOTES 17 The specimen area corresponding to the area of filter examined in the PCM fibre counting methods is 0,785 mm2, and is equivalent to approximately 100 grid openings of a 200 mesh grid. 18 Some National Standards require that asbestos fibres longer than 2,5 µm, with diameters between 0,2 µm and 3,0 µm be counted. Use a magnification of x 5 000 for counting fibres within these dimensional ranges. 19 The minimum aspect ratio for definition of a fibre in PCM fibre counting methods and in some National Stan- dards is 3/1. Use of a 3�1 aspect ratio is permitted in this International Standard, if this aspect raiio is mentiored in the test report. The test reports shall include all of the items listed in clause 11. � o ISO Annex F tnormative) Calculation of results F.1 General The results should be calculated using the procedures specified below. The results can be conveniently cal- culated using a computer programme. F.2 Test for uniformity of distribution of fibrous structures on TEM grids A chek shall be made using the chi-square test, to determine whether the asbestos structures found on individual grid openings are randomly and uniformly distributed among the grid openings. If the total number found in k grid openings is n, and the areas of the k individual frid openings are designated A� to Ak, then the total area of TEM specimen examined is i=k A=�A; ;_, The fraction of the total area examined which is rep- resented by the individual grid opening area, p;, is given by A;/A. If the structures are randomly and uni- formly dispersed over the k grid openings examined, the expected number of structures falling in one grid opening with area A; is np;. If the observed number of structures found on that grid opening is n;, then x2 _ �` �nt — nP�� 2 L, nPr r=� This value shall be compared with significance points of the chi-square distribution, having (k— 1) degrees of freedom. Significance levels lower than 0,1 % may be cause for the sample analysis to be rejected, since this correspond to a very inhomogeneous deposit. If the structure count fails this test, the precision of the result will be uncertain, and if new air samples cannot be collected, additional grid openings may be exam- ined or the sample may be prepared by an indirect method. ISO 10312:19951E) F.3 Calculation of the analyticat sensitivity Calculate the required analytical sensitivity S, ex- pressed in number of structures per litre, using the following equation: s = 9v where Af is the area, in square millimetres, of sam- ple collection fi�ter; A9 is the area, in square millimetres, of TEM specimen grid opening; k is the number of grid openings examined; V is the volume of air sampled, in litres. F.4 Calculation of the mean and confidence interval of the structure concentration In the structure count made according to this Inter- national Standard, a number of grid openings have been sampled from a population of grid openings, and it is required to determine the mean grid opening structure count for the population on the basis of this small sample. The interval about the sample mean which, with 95 % confidence, contains the population mean, is also required. F.4.1 Calculation of the mean structure concentration Calculate the mean structure concentration C, ex- pressed in number of structures per litre, using the following equation: C=Sn 43 ISO 10312:1995�E) where is the analytical sensitivity, expressed in number of structures per litre; is the total number of structures found on all grid openings examined. F.4.2 Caiculation of confidence intervals The distribution of structures on the grid openings should theoretically approximate to a Poisson distri- bution. Because of fibre aggregation and size- dependent identification effects, the actual structure counting data often does not conform to the Poisson distribution, particularly at high structure counts. An assumption that the structure counting data are dis- tributed according to the Poisson distribution can therefore lead to confidence intervals narrower than are justified by the data. Moreover, if the Poisson distribution is assumed, the variance is related only to the total number of structures counted. Thus, a par- ticular structure count conducted on one grid opening is considered to have the same confidence interval as that for the same number of structures found on many grid openings. However, the area of sample actually counted is very smail in relation to the total area of the filter, and for this reason, structures shall be counted on a minimum of four grid openings taken from different areas of the filter in order to ensure that a representative evaluation of the deposit is made. At high structure counts, where there are adequate numbers of structures per grid opening to allow a sample estimate of the variance to be made, the distribution can be approximated to a Gaussian, with independent values for the mean and variance. Where the sample estimate of variance exceeds that implicit in the Poissonian assumption, use of Gaussian statis- tics with the variance defined by the actual data is the most conservative approach to calculation of confi- dence intervals. At low structure counts, it is not possibie to obtain a reliable sample estimate of the variance, and the distribution also becomes asymmetric but not neces- sarily Poissonian. For 30 structures and below, the distribution becomes asymmetric enough for the fit to a Gaussian to no longer be a reasonable one, and estimates of sample variance are u�reliable. Accord- i�gly, for counts below 31 structures, the assumption of a Poisson distribution shail be made for calculation of the confidence intervals. 44 r� � F.4.3 Example of calculation of Poissonian 95 �'o confidence intervals For total structure counts less than 4, the lower 95 % confidence limit corresponds to less than 1 structure. Therefore, it is not meaningful to quote lower confidence interval points for structure counts of less than 4, and the result shall be recorded as "less than" the corresponding one-sided upper 95 % confidence limit of the Poisson distribution, as fol- lows: 0 structure = 2,99 times the analytical sensitivity 1 structure = 4,74 times the analyticai sensitivity 2 structures = 6,30 times the analytical sensitivity 3 structures = 7,75 times the analytical sensitivity For total counts exceeding 4, the 95 % confidence intervai shall be calculated using the values shown in table F.1. Table F.1 gives the upper and lower limits of the two-sided Poissonian 95 % confidence interval for structure counts up to 470. F.4.4 Example of calculation of Gaussian 95 % confidence intervals Calculate the sampie estimate of variance s2 using the following equation: i=k �(n; — nPr�Z sz = ' _' (k-1) where n; is the number of structures on the ith grid opening; n is the total number of structures found in k grid openings; p; is the fraction of the total area examined represented by the ith grid opening; k is the number of grid openings examined. If the mean value of the structure count is calculated to be n, the upper and lower values of the Gaussian 95 % confidence interval are given respectively by and n ts �=k+� k � o ISO n ts � k V k where �„ 4 n r s k is the upper 95 % confidence limit; is the lower 95 % confidence limit; is the total number of structures in all grid openings examined; is the value of Student's test (probability 0,975i for (k — 1) degrees of freedom; is the standard deviation (square root of sample estimate of variance); is the number of grid openings examined. F.4.5 Summary of procedure for calculation of results In summary, structure counting data shall be calcu- lated as foilows: No structures detected The structure concentration shall be reported as less than the concentration equivalent ot the one- sided upper 95 % confidence limit of the Poisson distribution. This is equal to 2,99 times the analyt- ical sensitivity. From 1 to 3 structures When 1 to 3 structures are counted, the result shall be reported as less than the corresponding one-sided upper 95 % confidence limit for the Poisson distribution. These are 1 structure = 4,74 times the analytical sensi- tivity 2 structures = 6,30 times the analytical sensi- tivity 3 structures = 7,75 times the analytical sensi- tivity From 4 to 30 structures The mean structure concentration and the 95 % confidence intervals shall be reported on the basis of the Poissonian assumption, using the values shown in table F.1. ISO 10312:1995(E) More than 30 structures When more 30 structures are counted, both the Gaussian 95 % confidence interval and the Poissonian 95 % confidence interval shall be cal- culated. The larger of these two intervals shall be used to express the precision of the structure concentration. When the Gaussian 95 % confi- dence interval is selected for data reporting, the Poissonian 95 % confidence interval shall also be mentioned. F.5 Calculation of structure length, width, and aspect ratio distributions The distributions ail approximate to logarithmic- normal, and therefore the size range intervais for cal- culation of the distribution shall be spaced logarithmicaily. The other characteristics required for the choice of size intervals are that they should allow for a sufficient number of size classes, while still re- taining a statistically.valid number of structures in eacti class. Interpretation is also facilitated if each size class repeats at 10 intervals, and if 5 µm is a size ciass boundary. A ratio from one class to the next of 1,468 satisfies all of these requirements and this value shall be used. The distributions, being approximately logarithmic-normal, when presented graphically, shall be plotted using a logarithmic ordinate scale and a Gaussian abscissa. F.5.1 Calculation of structure length cumulative number distribution This distribution allows the fraction of the total num- ber of structures either shorter or longer than a given length to be determined. It is calculated using the following equation: i=k �n' C'�}��k = �_ p x 100 �n; r=i where C(P)k is the cumulative number percentage of structures which have lengths less than the upper bound of the kth class; n; is the number of structures in the rth length class; P is the total number of length classes. 45 ISO 10312:1995(Ej �, � s F.5.2 Calculation of structure width cumulative number distribution This distribution allows the fraction of the total num- ber of structures either narrower or wider than a given width to be determined. It is calculated in a similar way to that used in F.5.1, but using the structure widths. F.5.3 Calculation of structure aspect ratio cumulative number distribution This distribution allows the fraction of the total num- ber of structures which have aspect ratios either smaller or larger than a given aspect ratio to be de- termined. It is calculated in a similar way to that used in F.5.1, but using the structure aspect ratios. Table F.1 - Upper and lower limits of the Poissonian 95 9'o confidence intervai of a count Structure Structure Structure count �ower limit Upper limk Lower limit Upper limit count count �ower limh Upper limit � 0 3,689�� 46 33,678 61,358 92 74,164 112,83 � 0,025 5,572 47 34,534 62,501 93 75,061 113,94 z 0,242 7,225 48 35,392 63,642 94 75,959 115,04 3 0,619 8,767 49 36,251 64,787 95 76.858 116,14 4 7,090 10,242 50 37,112 65,919 96 77,757 117,24 5 1,624 11,669 51 37,973 67,056 97 78,657 118,34 6 2,202 13,060 52 38,837 68,192 98 79,557 119,44 7 2,814 14,423 53 39,701 69,326 99 80,458 120,53 8 3,454 15,764 54 40,567 70,459 100 81,360 121,66 9 4,715 17,085 55 41,433 71,591 110 90,400 132,61 10 4,795 18,391 56 42,301 72,721 120 99,490 143,52 � 1 5,491 19,683 57 43,171 73,851 130 108,61 154,39 12 6,201 20,962 58 44,041 74,979 140 117,77 165,23 13 6,922 22,231 59 44,912 76,106 150 126,96 176,04 14 7,654 23,490 60 45,785 77,232 160 136,17 186,83 15 8,396 24,741 61 46,658 78,357 170 145,41 197,59 16 9,146 25,983 62 47,533 79,482 180 154,66 208,33 17 9,904 27,219 63 48,409 80,605 190 163,94 219,05 18 10,668 28,448 64 49,286 81,727 200 173,24 229,75 19 11,440 29,671 65 50,164 82,848 210 182,56 240,43 2� 12,217 30,889 66 51,042 83,969 220 191,89 251,10 21 13,00 32,101 67 51,922 85,088 230 201,24 261,75 22 13,788 33,309 68 52,803 86,207 240 210,60 272,39 23 14,581 34,512 69 53,685 87,324 250 219,97 283,01 24 15,378 35,711 70 54,567 88,441 260 229,36 293,62 25 16,178 36,905 71 55,451 89,557 270 238,75 304,23 26 16,983 38,097 72 56,335 90,673 280 248,16 314,82 27 17,793 39,284 73 57,220 91,787 290 257,58 325,39 28 18,606 40,468 74 58,106 92,901 300 267,01 335,96 29 19,422 41,649 75 58,993 94,014 310 276,45 346,52 30 20,241 42,827 76 59,880 95,126 320 285,90 357,08 31 21,063 44,002 77 60,768 96,237 330 295,36 367,62 32 21,868 45,175 78 61,657 97,348 340 304,82 378,15 33 22,715 46,345 79 62,547 98,458 350 314,29 388,68 34 23,545 47,512 80 63,437 99,567 360 323,77 399,20 35 24,378 48,677 81 64,328 100,68 370 333,26 409,71 36 25,213 49,840 82 65,219 101,79 380 342,75 420,22 37 26,050 51,000 83 66,111 102,90 390 352,25 430,72 38 26,890 52,158 84 67,003 104,00 400 361,76 441,21 39 27,732 53,315 85 67,897 105,11 410 371,27 451,69 40 28,575 54,469 86 68,790 106,21 420 380,79 462,18 41 29,421 55,622 87 69,684 107,32 430 390,32 472,65 42 30,269 56,772 88 70,579 108,42 440 399,85 483,72 43 31,119 57,921 89 71,474 109,53 450 409,38 493,58 44 31,970 59,068 90 72,370 110,63 460 418,92 504,04 45 32,823 60,214 91 73,267 111,73 470 428,47 514,50 t) The one-sided upper 95 °/a confidence limit for 0 structures is 2,99. 46 n � G o ISO Annex G (informative) Strategies for coliection of air samples G.1 General An important part of the sampling strategy is a state- me�t of the purpose of the sampiing programme. A sufficient number of samples shouid be collected so that the site is well characterized to the precision and accuracy desired, and also ensure that sample filters appropriately loaded for TEM analysis are obtained from all of the sampling locations. G.2 Air sample collection in the outdoors environment Weather conditions restrict the ability to collect satis- factory air samples in the outdoors environment, and whenever possible, sampling should be carried out in low-wind, low-humidity conditions. Detailed records of the weather conditions, windspeed and direction during the sampling period should be made. All avail- able i�formation concerning local topography, and the types and positions of sources should be recorded. Sequential multipoint sampling is necessary to pro- vide adequate characterization of complex sites and sources. It is recommended that multiple samples are taken upwind and downwind of the site, with a mini- ISO 10312:1995(E) mum of two samples in the downwind position ex- pected to experience the maximum airborne concentration. The locations of the samplers shouid be carefully recorded. G.3 Air sample collection inside buildings Air samples are often collected inside buildings in which asbestos-containing construction materials are present, in order to determine whether these materi- als contribute to the asbestos fibre concentration in the building atmosphere. The optimum positions for collection of air samples can only be determined after a complete survey of the building to establish air movement patterns. Multiple samples should be col- lected in the area where asbestos building materials are present, and control samples should be collected in an adjacent area where no airborne asbestos fibres would be expected. The intakes for air conditioning systems are frequently used as the collection lo- cations for control samples. Whenever possible, static samples should be taken over a period exceeding 4 h during normal activity in the building, at face ve- locities of between 4 cm/s and 25 cm/s. 47 ISO 10312:1995(E) Annex H (informative) Methods for removal of gypsum fibres it is common to find fibres of calcium sulfate (gypsum) in airborne particulates collected in buiidings and urban environments, and particularly in samples collected where demolition or construction work is in progress. The fibres are readily released when plas- ters and cement products are disturbed. In some cir- cumstances, particles of calcite or dolomite collected on an air filter can react with atmospheric sulfur diox- ide, to form long fibres of gypsum. Gypsum fibres can give rise to high fibre counts by both opticai and electron microscopy. The gypsum fibres are often 2 µm to 6 µm long, with aspect ratios greater than 10/1. Sometimes, these fibres appear similar to amphibole asbestos fibres, and in some samples they can be morphologically very similar to chrysotile. In the TEM, the larger fibres have high contrast and at high magnification often exhibit a characteristic mottied appearance which changes under electron beam irradiation. Some gypsum fibres, however, are not easily discriminated from asbestos without ex- amination by EDXA. TEM specimens which contain many such gypsum fibres require an extended exam- ination time in the TEM, because it is necessary to W � ISO � examine each of these fibres by EDXA before it can be rejected. It is possibie to remove gypsum fibres selectively by water extraction. A Jaffe washer (7.3.7), or a condensation washer (7.3.8), should be prepared, but using a water (6.1) as the solvent. The TEM speci- mens, which have been previously prepared and ini- tially examined in the TEM, should be placed in the washer to allow dissolution of the fibres. If a Jaffe washer is used, the treatment time can be reduced by heating the washer to 90 °C to 100 °C for a few minutes. If a condensation washer is used, the gypsum fibres wi►I be dissolved by treatment for ap- proximately 10 min. The effect of this treatment is to remove the gypsum fibres, leaving carbon replicas (7.3.11) �vhich are readily distinguished from asbestos fibres. NOTE 20 This procedure should be used only when ex- amination of the untreated TEM specimen grids shows the gypsum fibres to be isolated from any asbestos fibres present. Losses of asbestos fibres may occur if matrices of gypsum and asbestos are exposed to this procedure. �- a ISO ISO 10312:1995(E) � - ; � f a Annex J (informative? 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(19631: Rock-formfig minerals. Longmans, London. [10] Federal Register (1987): Asbestos-containing maierials in schools. U.S. Environmental Pro- tection Agency. Vol. 42, No. 210, October 30, 1987, pp. 41826-41905. [11] GAR�, J. A. (Editor) (1971): The Electron Optical Invesiigation of Clays. Mineralogical Society, 41 Queen's Gate, London S.W. 7. [12] GazE, R. (1965): The physicai and molecular structure of asbestos. Annals of the New York Academy of Science, Vol. 132, pp. 23-30. [13] HAWTHORNE, F.C. (1983): The crystal chemistry of the amphiboles. Canadian Mineralogist, Voi. 21, part 2, pp. 173-480. [14J HiRscH, P.B., HowiE, A., NiCHo�SON, R.B., PASHLEY, D.W. and WHELAN, M.J. (1965): Elec- tron microscopy of thin crystais. Butterworths, London, pp. 18-23. [15] HOLLAHAN, J.R, and BELL, A.T. (Editors) (1974): Techniques and applications of plasma chemis- try. Wiley, New York. [16] International Centre for Diffraction Data (1987): Powder diffraction file. Internationai Centre for Diffraction Data, 1606 Park Lane, Swarthmore, Pennsylvania 19081, USA. [17� International Mineralogical Association (1978): Nomenclature of amphiboles (compiled by B.E. Leake); Canadian Mineralogist Vol. 16, p. 501. [18] international Organization for Standardization (Organisation internationale de normalisation) (1993): ISO 8672:1993, Air quality — Determi- nation of the number concentration of airborne 49 ISO 10312:'9995(Ej � ISO � inorganic fibres by phase contrast optical microscopy — Membrane filter method. [19] JAFFE, M.S. (1948): Handling and washing fragile replicas. J. Applied Physics, 19, p, 1187. [20] JoY, D.C., ROMIG, Jr. and GOLDSTEIN, J.I. (Edi- tors) (1986): Princip/es of analytical elecfron microscopy. Plenum Press, New York and �ondon. [21] LEooux, R.L. (Editor) (1979): Short course in mine�alogical iechniques of asbestos determi- nation. Mineralogical Association of Canada, Department of Mineralogy, Royal Ontario Mu- seum, 100 Queen's Park, Toronto, Ontario Canada M5S 2C6. tional Safety and Health, 4676 Columbia Park- way, Cincinnati, Ohio 45226, USA. [29] NATAEILA, M.G. (1966): Experimenial statistics: National Bureau of Standards Handbook 91. U.S. Government Printing Office, Washington, D.C. 20402. [30] ORTiz, L.W. and IsoM, B.L: (1974): Transfer technique for electron microscopy of inembrane filter samples. American lndusirial Hygiene As- sociacion Journal, 35, 7, pp. 423-425. [31] PEARSON, E.S. and HARTLEY, H.Q. (1958): Biometrica tables for statisticians, Vol. 1, Cambridge University Press, 32 East 57th Street, New York, N.Y. 22, USA. [22) LEVADIE, B. (Editor) (1984): Definitions for [32) RHOADES, B.L. (1976): XJDENT-A computer asbestos and oiher health-related silicates. technique for the direct indexing of electron dif- ASTM Special Technical Publication 834. Ameri- fraciion spot pafterns. Research Report 70/76. can Society for Testing and Materials, 1916 Dept. of Mechanical Engineering, Univ. of Race Street, Philadelphia, Pennsylvania 19103, Canterbury, Christchurch, New Zealand. USA. [23] MICHAEL, J.R. and WILLIAMS, D.B. (1987): A consistent definition of probe size and spatial resolution in the analytical electron microscope. J. Mic., 147, pp. 289-303. [24] MICHAELS, �. and CHISSICK, S.S. (Editors) (1979): Asbesios: Properties, Applications and Hazards, Vol, 1, Wiley, New York. [25] National Bureau of Standards Special Publication 506 (1978): Workshop on asbesios: definitions and measurement methods. U.S. Government Printing Office, Washington, D.C. 20402. [26] National Bureau of Standards Special Publication 619 {1982): Asbestos siandards: material and analytical methods. U.S. Government Printing Office, Washington, D.C. 20402. [27) National Institute for Occupational Safety and Health (1989): N/OSH Method 7400, Revision #3, 5(15/89. U.S. Department of Health and Hu- man Services, Public Health Service, Centers for Disease Control, National Institute for Occupa- tional Safety and Health, 4676 Columbia Park- way, Cincinnati, Ohio 45226, USA. [28] National Institute for Occupational Safety and Health (1989�: N/OSH Method 7402, Revision #1, 5/15/89. U.S. Department of Health and Hu- man Services, Public Health Service, Centers for Disease Control, Nationai Institute for Occupa- 50' [33] R�tvG, S.J. (1980): Identification of amphibole fi- bers, including asbestos, using common elec- tron diffraction patterns. In: Electron Microscopy and X-ray Applications to Environmental and Occupational Health Analysis, (Ed. P.A. Russeil), Vol. II, Ann Arbor Press, Ann Arbor, Michigan 48106, USA. [34] RuSSE��, P.A. and HUTCHINGS, A.E. (1978): Electron Microscopy and X-ray Applications to Environmental and Occupational Health Analy- sis. Ann Arbor Science Pubiishers Inc., P.O. Box 1425, Ann Arbor, Michigan 48106, USA. [35] SMALL, J.A., HEINRICH, K.F.J., NEWBURY, D.E. and MYKLEBUST, R.L. (1979): Progress in the devel- opment of the peak-to-background method for the quantitative analysis of single particlas with the electron probe. Scanning Efeciron Microscopy/1979�11, (O. Johari, Ed.). SEM Inc., AMF O'Hare, Chicago, Iliinois 60666, USA. [36] SMALL, J.A., STEEL, E.6. and SHERIDAN, P.J. (1985): Analytical standards for the analysis of chrysotile asbestos in ambient environments. Analytical Chemistry, 57, pp. 204-208. [37] SMITH, J.E. and JORDAN, M.L. (1964): Math- ematical and graphical interpretation of the log- normal law for particle size distribution analysis. J. Colloid Science, 19, pp. 549-559. [38] SPURNY, K.R., ST08ER, H„ OPELIA, H. and WE�SS, G. (1979): On the evaluation of fibrous .�• o ISO particles in remote ambient air. Science of ihe Total Environment/1979/II, pp. 1-40. [39] SPURNY, K.R. (Editor) (1986): Physical and chemica! characterization of individual airborne particles. Wiley, New York. [40] STEEL, E.B. and SMALI, J.A. (1985): Accuracy of transmission electron microscopy for the analysis of asbestos in ambient environments. Analytical Chemistry, 57, pp. 209-213. [41] STEEI, E.B. and WYLIE, A. (1981): Mineralogical characteristics of asbestos. In: Geology of ISO 10312:1995(Ej Asbestos Deposiis, (P.H. Riorden, Ed.), SME-AIME, pp. 93-101. [42] WENK, H.R. (Editor) (1976): Eleciron microscopy in mineralogy. Springer-Verlag, New York. [43] YAOA, K. (1967): Study of chrysotile asbestos by a high resolution electron microscope. Acta Crystallographica, 23, pp. 704-707. [44] ZussnnaN, J. (1979): The mineralogy of asbestos. In: Asbestos: Properties, Applications and Haz- ards, John Wiley and Sons, pp. 45-67. 51 ISO 10312:19951E�� � ISO � .t � i i ?. ICS 13.040.20 Descriptors: air, quality, air pollution, tests, determination, particle density (concentratioN, asbestos, microscopic analysis. Price based on 51 pages ' QAPP Appendix C June 2, 2000 Revision 0 Appendix C _ Standard Operating Procedure for the Screening Analysis of Soil and 5ediment Samples for Asbestos Content SOP:EIA-INGASED2.�OP Asbestoe in Sedimejnts/Soils 1/11/99 � Page 1 oP 7 EPA, xeqion I Standard operating Proa�dura for the sornening Analyeia o! Boil and &�dimant Samples tor Asbestos Cahta�t Pr�pared for: Offia• o� EAvironm�nt�l Measuremant Aad Evaluntion �.8. EPA, &�qiott I R�visea by: L�'vl 8aott CliiterC, at, Invsstigation� Ax►d Analyeie Ui� t, IIdE � , �.___,--�_ � � , f -i Y Agprov�d by: Ag�ea Yn n ave, Ph.D., {ZA pfficer,j ti nd Aaalysia Uuit, Q�i$; Approv�d by : ! a 9 /3 ( . abert . Maxtfaid, Man�ger, =nve�tiqa�ians Aad Aanlyeis Dnit, OF.2�E SOP:EIA-INGASED2.Spp Asbestos in Sedime�ts/sails 1/11/99 Page 2 of 7 St ►_ This SOP details �he sampla analysis protocol for detertnining the ashestos cont�nt of soi2 and sediment samples. Sample clean up with a sieve washing is followed by stereo microscope and polarized light microscope examittation. This protocol is a semi-quantitative methed, used only far visually estimating percentage levels of asbestos in a soil or sedimerst sample. 2 . O Pur�►88Q r To ensure that the protocole for analysis of aebestoe in sedime�tfsoil samples are consietently applied by all analysts. 3 o S�agR an4 Aptlication• This protocol is not a�'reference" method. It was de�eloped ou� oi neceaeity to facilitate finding asbestos fibars in a soil �r muc9 (sediment) sample that does not cantain any obvious asbestos filbers or asbestos-containing building or product materials when examined�dry (or wet) using a et�reo microscope at 10?C or 2oX magnificatian. It;has been used for asbestos content in order to help delineate contaminated areas. It has proven to be an extremely sensitive method capable of f ir�ding very small amounts of asbestos fibere in a soil or sediment matrix. Glasaware ar ather materials, supplies, etc., mentioned below in the pracedures are those being used in this laboratory. Other mate�ia2s may be substituted as long as the primary purpose of the protocol is followed, namely: to find asbestos fibers in the sample. Identification of fibrous components is accomplished by the routina Polari$ad Liqht Micro3aogy (PLidj (with dispersion staining) method. (See EPA approved method references on page S,) �.o De�initians: PLM - Polarized Light Microacopy 5.o Ssait� aaQ safstv Warainqs• Asbestos fibers ca� have serious etfects on your health if irihaled. Sample contai.ners should be initially opened in the HEPA fil'kered haod. Care must be taken when handling any unknown samples to prevent airborne a6bestos. PLEA8E RECYCL� THI6 PApER SOP:EIA-ZNGASED2.5flP Asbestos in SedimentsJSoils 1/I1/99 Page 3 of � YTI PRQC E8 1. A representative portiort of the sample is removed from the eample container after thoraughly mixing for homogeneity� Because asbestos fibers us�ally cannot be seen because oi the compQsition of the sample matrix such as the dirt, sand, mud, vegetation, water, etc., steps must be taken to cle�n up �he sample ta the point where the asbestos fibers, if any, may be seen using the stereomicrascope at lOX to 20 X magnification. A stereomiaresoope ie maadatorp �or this protaool. ' 2. To eliminate interfering particles, a 16mm ID by 15amm long, goo� quality PYREX or KIMAX test tube (not a fraqi2e disposable tube) is used to gemove portiane of the well-mixed soil/sediment sample from several places in the sample cantainer by pushing it into the sample to accumulate a sample depth of about 2.5 inches (65mm) in the test tube. A glase or plastic stirring roc2 is usad to push the sample down into the tube and fibez-free (tap) wate� is added for shaking purpases. The soil and water mixture is shaken vigorously to loosen and separate the fines and other components of tha sample and:the cant$nts of the test tube are then poured into a 3 inch ID, 60 mesh Q250 micrometers) sieve, This serv�s to eliminate, ox greatly reducer collloidal material, ffne sand, silt and other nan-fibrous particulates from the samp].e. More water is added to the tube, shaken and dumped into the sieve. i�epeat this step until the tube is clean. The sample in the sieve is then rinsed untiil clean (clear water running through the sieve} with a fairly fine, �r�ssuri2ed stream af water from a plastic wash bottle. All of the material remaining in the sieve is then washed from the si,eve screen using a stream af water from the rinse battle into a square plastic caeighing dish of abaut looml liquid capacity. Use just enough water to compl�tely cover the sample in the dish about 1/8th inch or so for examina�ion with tt�e stereo microscope. � After the cleaned sample is transferred to the weighing dieh for exa�ination, thoroughly rinse the sieve and test tube under running tap water (pre�ferably aerated to minfmize splashing) and carryover wilZ not be a problem from eample to sample. It is a good idea to carry out all washirig af the sample fines over a plastic dishpan or other container set into th� sink basin in orderito capture the fines and keep them from clogging the eink drain trap. A,;fter a settling period, the overlying water may be poured off and the fines%�nud dispoaed of separately. • PLEASE &�CYCLE T$I$ PAPER SOP:EIA-INGA5ED2.S p AebestQs ih sedime�ts/sails 1/12/99 Page 4 of 7 NOTE: 5ince the purpose af the tesG is to find out if the eoil or mud samg a significant amount of asbestos (>1�) that can be identified using technique, ��1 porticns ot tha sampl� are to be eRa.2ain�d excet�t thos ��,i.ah umas ihrQuah th� dlove contains PLM 3. After examining them for asbestos fibers, floating pieces of a�ganic material such as roots, sticke, leaves, etc., may be remaved to get`a better view af the rest of the sample in the dish. Frequently, raot struct�res iound in surface soils will trap asbestos fibers durinq the shaking procesis and are a good place to look for the fibers. The sample is then caraf��lY and systematically examined under the stereo microscope at lOX-20X magnification for visible asbestos f ibers and fiber bundles. A good, bright, fo�used light gource such as a Nicholas transformer-base external illuminator is v�ry helpful here. The f ibers tend to stand out, shine, flash, etc., in the clean water matrix. Poking and stirring the �ample �uith forcepe and/or dissectiMg needles will help to Zocate the fibers. IP no fibera are seen, gantly shaking the weighing dish to redistribute particles will sometimes turn ug previQusly hidden fibers when scanning the sample a secand time. Suspect fibers are removed with sharp forceps and placed upon a c2ean microscape slide, � 4. After picking as many suspect fibers ar other material from the�sample as necessary to determine its content, the slide preparation is allowed ta dry and prepared for PLM analysis using an appropriate high-dispersion refractive index liquid and coverslip. 5. xext, the slide preparation is examined with a polarized liqht microscope (PLM) with dispersion staining to fdentify any fibers found. Standa�d, EPA approved PLM procedures axe used to identify any asbestos fibers fourid as to specific type and form. The identification of asbestos using PLM is rapid and unequivocal due to the unique optical crystallographic praperties of � morpholagy, refractive indices, elongation, angle of extinction, dispersion and hirefringence. S1ide preps are examined for each sample with suspect fibers to confirm the presence of asbestas. s. If asbestos fibers are identified, return to the sieved sample u,hcler the stereo microscope, observe the remain3ng asbestos fibers and bundles af fibers, and make a visual estimate of the percentage asbestos content in the �ho1a sampl• including tne materfal prevfously wash�d tbrouqh the aiave. (This is aIl based on asbestos fibers seen using lOX to 20X magnification undes� the stereomicroscape.) Obviously, many of the finest fibers pass through�th2 sieve and the finest ones remaining can't be seen at 20x magnification, but., this protocol is not me�nt to be used as a auantitative method It is useful, hawever, ta determine whether or not the soil or aediment is contaminated with siqnificant amounts of asbestos. (> than 1� by volume). PL�148E RECYCLE T8I8 PAPER SOP;EIA-IN�ASED2.SbF Asbestos in 5edime�tsJScils 1/11/99 Page 5 of � 7. As a rule, if asbestos fibera and%or fiber bundles can't be fouD�d relatively quickly and eaei].y (one to two minutes) in tha cleaned up�sample under the stereo microscope, the percent ashestos contant is most likely less than Q.1$ and certainly less than 1.0� : Ona shauld be able to find;asbestos fibers in a salnple containing more than 1.0� in a few seconds up to a one miriute examination under the stereo microscope. 8. Usually, as much of the original sample as possible is returned'to the ariginal sample container. If saving the fines is required for further examination by other methods, use individual heakers to catch the sieve washings containing the sand and silt componants. 9. The sample containers are then resealad before storage, disposal or return to the organization that requested the analyses. 10. If further information is required on this protoco� or if anyone has found a better way ta find and estimate asbestos fibers in muds or soils, please contact: Scott Cl�.fford or Dan Boudreau USEPA, REGION 1 6� Westview St. Lexington, MA 02421 Telephone; (781) 860-9340 APPRQVED EPA Bi1LIt AlQALX�IB PROTaCOL; 40 CFR FART 763, SUBPART F, APPENDIX A � or, "ASBESTOS IDENTIFICATION'�- Waiter C. McCrone, 1987, McCrone Rasearch Institut�� Chicago, Ill. See alsa, ",�,sbestos content In Bul.k Insulation Samples• Visual Estimat�s and Weight ComDosS.t�on"- US EPA, EPA-560/5-88-Q11, September, 1988. PLEABE RECYCLE TIiIB FAPE& SQP:EIA-ZNGASED2.SIOP Asbestos in Sedim�nts/Soils lJll/99 Page 6 vf 7 .�� 2��lvtical procequra Adde�dum for �ora Aocur��� Ouantitatioa• . ADDENDIIli TO "PROTOCOL SOR BCxEENI�d B�IL AND SED2M�NT SA?iPLEB FOR�ASSHBT08 CONTEI�tT DBED 8Y TH� O.B. ENFZROAII�lENTAL PAOTBCTION At�ENCY� REOZON I LABdR.AT4RY" A+idaadum dntad: Auguat 19sT This acidendum can be used to more accurately quantitatQ the volume o� ashestos in soil and sediment samples. It ie meant to give the analyst a good vieual estimate af the fine materials volume which pass through the mesh sieve relative tg the origina2 sample volume analyzed. It must be used in canjunction with the above mentioned protocol. $�mple Pr�paratian Anni�tioa�. Praaedure• 1. Transfer a well mixed gortion of homogenized soil into the�plastic weigh dish. Cover the bottom of the dish with a thin {lcmp layer. �uantitatively transfer the soil/sediment inta the test tuba using a wide mouth funnel. Fiber-free (tap) water can be used to �elp wash f ines into the test tube. A qlass or plastic stirring rod�is used ta push tha sample down into the test tube end artd to break-u$'� atly soil clumps. Wash tha test tube sidea down with a stream of water. Let the soilJwater mix settle such that the valume of material'in the test tube can be measured. Measure from the bottom of the�test tube to the top of the settled soil with a ruler and record the value (i. e. , 4.5c1n) . After the soil volume measurement, continue the analytical'procedure (i.e., shake vigorously to looaen and separate the fines, �pour contents into sieve for clean-up, transfer sample companen� left in sieve to weigh dish for examination, etc.) After complete examination and determination af asbestas ccpntent of the eample portion in the weigh aish which did not pass throttgh the � sieve (using stereo microscope and PLMj,� the sample in the wei.gh dish is quantitatively transferred back into the tast tube and allowed to settle. After settling, the vvlume af material in the tes�. tube is again measured and reoorded (i.e., 2.Ocm). . PLEASE RECYCL$ THIS PAPE& SOP:EIA-INGASED2.SQP Asbestos in Sedime�ts/Soils ljll/99 Page 7 of 7 � Determine the asbestos contant of the sample as follows: $ asbestos in samp2e Volume of eample which portion which did not X did not pass throuqh pasB through the sieve �iev� Initial sample volume PLEABE &ECYCL� THIB P�PER QAPP Appendix D June 2, 2000 Revision 0 Appendix D ASTM Standard Test Method D 4959-00 Determination of Water (Moisture) Content of Soil by Direct Heating ���� Designation: D 4959 — 00 Standard Test Method for Determination of Water (Moisture) Content of Soil By Direct Heating' This standard is issued under the fixed designation D 4959; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses iodicates the year of last reapproval. A superscript epsilon (e) indicates an editorial change since the last revision or reapproval. i. Scope 1.1 This test method covers procedures for determining the water (moisture) content of soils by drying with direct heat, such as using a hotplate, stove, blowtorch, etc. 1.2 This test method can be used as a substitute for Test Method D 2216 when more rapid results are desired to expe- dite other phases of testing and slightly less accurate results are acceptabie. 13 When questions of accuracy between this test method and Method D 2216 arise, Method D 2216 shall be the referee method. 1.4 This test method is applicable for most soil types. For some soils, sueh as those containing significant amounts of halloysite, mica, montmorillonite, gypsum, or other hydrated materials, highly organic soils or soils that contain dissolved solids, (such as salt in the case of marine deposits), this test method may not yield reliable water content values. 1.5 The values stated in SI units are to be regarded as standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro- priate safety and health practices and determine the applica- bility of regulatory limitations prior to use. 2. Referenced Documents 2.1 ASTM Standards: D 653 Terminology Relating to Soil, Rock, and Contained Fluids2 D 2216 Test Method for Laboratory Determination of Water (Moisture) Content of Soil and Rock2 D 3740 Pracrice for Minimum Requirements for Agencies Engaged in the Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction2 D 4753 Specification for Evaluating, Selecting, and Speci- fying Balances and Scales for Use in Testing Soil, Rock, and Related Construcrion Materials2 � This test method is under the jurisdiction of ASTM Committee D-18 on Soil and Rock and is the d'uect responsibility o£ Subcommittee D18.08 on Special and Construction Control Tests. Current edition appcnved Mazch t0, 2000. Published Aprit 2000. Originally published as D 4959 — 89. Last previous edition D 4959 — 89 (1994). Z Annual Book ojASTM Standards, Vol 04.08. Copyright O ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States. 3. Terminology 3.1 Definitions All definirions are in accordance with Terms and Symbols D 653. 3.2 Definitions of Terms Specific to This Standard: 3.2.1 direct heating—a process by which the soil is dried by conductive heating from the direct application of heat in excess of 110�C to the specimen container, such as provided by a hot piate, gas stove or burner, heatlamps, or other heat sources. Direct application of heat by flame to the specimen is not appropriate. 3.2.2 water (moistur•e) content—the ratio, expressed as a percentage, of the mass of water in a given mass of soil to the mass of the solid particles. 4. Summary of Test Method 4.1 A moist soil specimen is placed in a suitabie container and its mass is determined. It is then subjected to drying by the application of direct heat untii dry by appearance, removed from the heat source, and its new mass is deternuned. This procedure is repeated until the mass becomes constant within specified limits. 4.2 The di$'erence between the masses of the moist speci- men and the dried specimen is used as the mass of water contained in the specimen. The water content (expressed as a percentage) is determined by dividing the mass of water by the dry mass of soil, mulriplied by 100. For a given soil type and speeimen size, the time to achieve a constant dry mass can be noted and used to estimate drying time for subsequent tests of the same soil type using the same size specimen and drying apparatus. 5. Significance and Use 5.1 The water content of a soil is used throughout geotech- nicai engineering practice both in the laboratory and in the field. The use of Test Method D 2216 for water content determination can be time consuming and there are occasions when a more expedient method is desirable. Drying by direct heating is one such method. Results of this test method have been demonstrated to be of satisfactory accuracy for use in field control work, such as in the deternunation of water content, and in the determination of in-place dry unit weight of SOIIS. 5.2 The principal objection to the use of the direct heating q� D 4959 for water content detetmination is the possibility of overheat- ing the soil, thereby yieiding a water content higher than would be deternuned by Test Method D 2216. While not eliminating this possibility, the incremental drying procedure in this test method wil( minimize its effects. Some heat sources have settings or controls that can also be used to reduce overheating. Loose fitting covers or enclosures can also be used to reduce overheating while assisting in uniform heat distribution. 53 The behavior of a soil when subjected to direct heating is dependent on its mineralogical composition, and as a result, no one procedure is applicable for all types of soils or heat sources. The general procedure of this test method applies to all soils, but test details may need to be tailored to the soil being tested. 5.4 When this test method is to be used repeatedly on the same or similar soil from a given site, a correction factor can usually be deternvned by making several comparisons between the results of this test method and Test Method D 2216. A conection factor is valid when the difference is consistent for several comparisons, and is reconfirmed on a regular specified basis. 5.5 This test method may not be appropriate when precise results are required, or when minor variarions in water content will affect the results of other test methods, such as borderline situations where small variations in the measured water content could affect acceptance or rejection. 5.6 This test method is not appropriate for specimens known to contain flammable organics or contaminants, and other test methods should be utilized in these situations. Nore 1—The quality of the results produced by this test method is dependent on the competence of the personnei performing it and the suitability of the equipment and faciliries used. Agencies that meet the criteria of Practice D 3740 are generally considered capable of competent and objective testing/sampling/inspec6on. Users of this test method are cautioned that compliance with Practice D 3740 dces not in itself ensure reliable results . Reliable results depend on many factors; Practice D 3740 provides a means of evaluating some of those factors. 6. Interferences 6.1 When tesring sand and gravel size particles, addirional care must be taken to avoid the possibility of particle shatter- ing. 6.2 Due to the localized high temperatures in the soil during testing, the physical characteristics of the soil may be altered. Degradation of individual particles may occur, along with vaporizarion, chemical transition, or loss of organics. There- fore, specimens used in this test method should not be used for other tests subsequent to drying (see Note 2). Nore,2—The subsequent use of specimens dried by direct heating in other test methods is discouraged. 7. Apparatus 7.1 Direct Heat Source Any source or heat that can be d'uected to the soil specimen to raise the specimen temperature to or above 110�C. Commonly used sources include electric, gas, butane or oil-fired stoves, and hotplates, blowtorches, heat lamps, hair driers, space heaters, etc. Heat sources that directly apply open flame to the specimen may cause extreme degra- darion of the specimen along with oxidarion of and depositing of soot in the specimen and should not be used. 7.2 Balances A balance having a minimum capacity of 2 Kg, and meeting the requirements of Specification D 4753 for a batance of 0.1-g readability. 7.3 Specimen Containers�uitable containers made of ma- terial resistant to corrosion and a change in mass upon repeated hearing, cooling, and cleaning. One container is needed for each water content determination. �.4 Container Handling Apparatus—Gloves or suitable holder for moving hot containers after drying. 7.5 Miscellaneous (as needed}—Mi}cing tools such as spatu- las, spoons, etc.; eye protection, such as safety glasses or goggles; cigarette papers, and lrnives. 8. Hazards 8.1 Container holders or gloves are recommended for han- dling hot containers. Some soil types can retain considerable heat, and serious bums could result from improper handling. 8.2 Suitable eye protection such as safety glasses or goggles is recommended due to the possibiliry of particle shattering during heating, mi�cing, or mass detemvnarions. 83 Highly organic soils, and soils containing oil or other contaminants may ignite during drying with direct heat sources. Means for smothering $ames to prevent operator injury or equipment damage should be available during testing. Fumes given off from contaminated soils or wastes may be toxic, and should be vented accordingly. 8.4 Due to the possibility of steam e�cplosions, or thermal stress shattering of porous or brittle aggregates, a vented covering over the sample container may be appropriate to prevent operator injury or equipment damage. This also pre- vents scattering of the test specimen during the drying cycle while aiding in uniform heating of the specimen. 9. Samples 9.1 Perform the water content determination as soon as pracrical after sampling to prevent water loss and damage to potentially corrodible containers. 9.2 Prior to testing, store samples in non-corrodible airtight containers at a temperature between approximately 3 and 30°C and in an azea that prevents direct exposure to sunlight. 10. Test Specimens 10.1 Select a representative portion of the total sample. If a layered soil or more than one soil type is encountered, select an average portion or individual portions of each, and note which portion(s) were tested in the report of the results. 10.1.1 For bulk samples, select the test specimen from the material after it has been thoroughly mixed. The mass of moist material selected shall be in accordance with Table l. TABLE 1 Test Specimen Masses Sieve Size Retaining More Than Minimum Mass of 10 % of Sample, mm Moist Specimen, g^ 2.0 (No. 10) 200 to 300 4.75 (No. 4) 300 to 500 19.0 (No. �/s) 500 to 1000 "l.arger specimens may be used and are encouraged. Generaliy, inherent test inaccuracies are minimized by using specimens with as large a mass as practicai. q� D 4959 10.1.2 For smali samples, select a representative portion in accordance with the following procedure: 10.1.2.1 For cohesionless soils, mix the material thoroughly, then select a test specimen having a mass of moist material in accordance with Table 1. 10.1.2.2 For cohesive soils, remove about 3 mm of material from the exposed periphery of the sample and slice the remaining specunen in half (to check if the material is layered), prior to selecting the test specimen. If the soil is layered, see 10.1. Breaking or cutting of cohesive sampies to approximately 6 mm particles speeds drying and prevents crusring or over- heating the surface while drying the interior. 10.2 Using a test specimen smaller than the minimum mass indicated in Table 1 requires discretion, though it may be adequate for the purpose of the test. Note a specimen having a mass less than the previously indicated value in the report of results. Nore 3—When working with a small sample containing a relatively large couse-grained particle, it may be appropriate not to include this particle in the test specimen, depending on the use of test resu(ts. If this is done, such exclusion should be noted in the report of the results. 10.3 When the result of a water content determinarion by the use of this test method is to be compared to the results of another method, such as Test Method D 2216, obtain a second specimen during selection of the specimen for this comparison. Take precaurions to obtain a specimen that represents the same water content as closely as possible. Protect the comparison specimens from water loss by transporting and storing the specimens in sealed containers. A correetion factor can be determined for use on subsequent water content deternvnations on the same soil types from the same site when the difference is relatively constant using several comparisons. Check the conection factor on a regulaz, specified basis. Recognize that different technicians, heat sources, and such may result in different correcrion factors. 11. Conditioning 11.1 Prepare, process, and test all specimens as quickly as possible to minimize unrecorded moisture loss. 11.2 Cut or break up the soil into small size aggregations to aid in obtaining more uniform drying of the specimen, taking care to avoid any loss of soil. 11.3 If the specimens are not being tested immediately, place the specimens in containers that can be closed and stored in an area not exposed to direct sunlight, to prevent loss of moisture prior to initial mass determinations. 12. Procedure 12.1 Deternvne the mass of a clean, dry container, and record. 12.2 Place the soil specimen in the container, and immedi- ately deternune and record the mass of the soii and container. 12.3 Apply heat to the soil specimen and container, taking care to avoid localized overheating. Continue hearing while stirring the specimen to obtain even heat distriburion. Continue applicarion of heat unrii the specimen first appears dry. A comparatively uniform color should result. Avoid localized bumt or darkened appearance of any part of the soil by intemuttent mixing and stirring. 12.3.1 Experience with a particular soil type indicates when shorter or longer initial drying periods can be used without overheating. Nore 4—A piece of dry, light-weight paper or tissue, such as cigarette paper, placed on the surface of the appazently dry soil will curl or ripple if the soil still contains significant water. 12.4 After an initial hearing period has been completed (soil appears dry), remove the container and soil from the heat source and cool to allow handling and prevent damage to the balance. Determine and record the mass of the soil and container. 12.5 Retum the container and soil to the heat source for an additional application of heat. 12.6 V�th a small spatula or lmife, carefully stir and mix the soil, taking care not to lose any soii. 12.7 Repeat 12.3 through 12.5 unfii the change between two consecutive mass detemunations would have an insignificant effect on the calculated water content. A change of 0.1 % or less of the dry mass of the soii for the last two detemunations should be acceptable for most specimens. 12.8 Use the final dry mass determination in calcularing the water content. 12.9 When rourine testing of similar soils is contemplated, the drying times and number of cycles may be established and correlated for each heat source and used for subsequent determinations. When pre-deternvned drying times and cycles are utilized, periodic verification in accordance with the procedure in 12.7 should be performed to assure that the results of the final dry mass detemunation are equivalent. 13. Calculation 13.1 Calculate the water content of the soil as follows: w=[(M� — MZ)/(Mz — M�)] X 100 = M,fM X 1Q0 (1) where: w = water content, %, M� = mass of container and moist specimen, g, M2 = mass of container and dried specimen; g, M� = mass of container, g, Mw = mass of water, g, and MS = mass of solid particles, g. 14. Report 14.1 Report the foilowing informarion: 14.1.1 Identification of the sample (material) being tested, by locarion (boring number, sample number, test number, etc.), 14.1.2 Water content of the specimen to the nearest 1%, 14,13 Indication of the test speciinen mass, including a note if less than the minimum indicated in Table 1, 14.1.4 Indicarion of test specimens containing more than one soil type (layered, and the like), 14.1.5 Indicarion of any material (size and amount) ex- cluded from the test specimen, 14.1.6 Initial mass of test specimen prior to drying, and the mass after the incremental drying periods, 14.1.7 Identificarion of the type of direct heat source, drying settings, drying times, and number of cycles used, when standardizecl drying is utilized, and 14.1.8 Identification of comparison test(s) if performed, the q� D 4959 method of test utilized and any correcrion factors applied (see Note 5). NorE 5—Water content determinations conducted in accordance with Test Method D 2216 or other methods may be rewrded on the same report. This is not a mandatory requirement, but may be convenient when the results of the two methods are to be compared. 15. Precision and Bias 15.1 Precision Test data on precision is not presented due to the nature of the soil materials being tested by this test method. It is not feasible and too costly at this time to have ten or more agencies participate in a round-robin testing program. Also, it is not feasible or too costly to produce mulriple specimens that have uniform physical properties. Any variation observed in the data is just as likely to be due to specimen variation as operator or laboratory tesring variation. 15.2 The precision of this test method is operator- dependent, and is a function of the care exercised in perform- ing the steps of the procedure, giving particular attention to careful controi and systematic reperirion of the procedures used. 15.2.1 Subcommittee D18.08 is seeldng any data from users of this test method that might be used to make a limited statement on precision. 153 Bias There is no accepted reference value for this test method, therefore, bias cannot be determined. 16. Keywords 16.1 acceptance tests; compaction control; density; direct heating; laboratory moisture tests; moisture content; moisture control; quality control; rapid method; soil moisture; test procedure SUIVIMARY OF CAANGES In accordance with Committee D-18 policy, this section identifies the location of changes to this standard since the last edition (1994) that may impact the use of this standard. (1) Editorially revised the title. (2) Editorially revised 1.2. (3) Revised Secrion 2 to include Practice D 3740. (� Revised Section 5 to include Note 1 referencing Practice D 3740. (5) Revised the numbering of exisring notes. (� Revised precision and bias statement to conform to D-18 policy. (� Added Summary of Changes. The American Society fo� Testing and Materials takes no position respectlng the validity of any patent rights asserted in connection with any ilem mentioned in this standard. Use�s of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibiliry. This standa�d is sub%ect to revislon at any time by the responsible technical committee and must be �eviewed every five years and if not revised, eithe� �eapproved or withdrawn. Yourcomments are invited eithe� forrevision of this slandard orfor additional slandards and should be addressed to ASTM Headquarters. Your comments will receive careful consideration at a meeting of the responsible technical committee, whicb you may aKend. !f you feel that your comments have not received a fair hearing you should make your views known to fhe ASTM Commlttee on Sfandards, at the address shown trelow. This standard is copyrighted byASTM, 100 BarrHarborDrive, PO Box C700, West Conshohocken, PA 19428-2959, United States. lndividual reprints (single oi multiple copies) of this standard may be obtained by contacting ASTM at the above address or af 610-832-9585 (phone), 6f0-832-9555 (fax), o� service@astm.org (�mail); ar through the ASTM website (www.aslm.org). QAPP Appendix E August 17, 2000 Revision 1 Appendix E EPA Method 100.1 Analytical Method for the Determination of Asbestos Fibers in Water PB83-260471 III lIII II II I I►1!Iliiil IIII IIII IIII III ANA�YTICAL METh'00 FCR �ET�R"1�?!M'� ?G� OF ASBESTOS FIBERS IN ��IA��� �y Eric J. Chatfield and �?. Jane �illon Flectron Optical Laboratory Department of Apptied Physics Ontario Research Foundation Sheridan Park 2esearch Corranunity Mississauga, Ontario, Canada LSK 133 Contract 68-03-2717 Project Officer J. �1acArthur I.ong Analytical Chemistry 3ranch Environmental Research Laboratory Athens, Georgia 30613 0 ENVtRONMENTAL RESEFRCH l�1BORATORY OF�ICE OF REScARCH AND DE1E�OpMEuT U.S. E�vIROr.m�ENTa� PROTECTi��v aGE"�CY ATHEVS, GEORGIA 30613 r�raoouctc e. NATIONAt TECHNICAL INFORMATION SERVICE uS :EP�p�yE�r p� ;C�r[AtE coo�.•a,r.. ..� ..... � TECHNICA� REPORT DATA ;!'�� ,,ar ,roJ lxun,� nr,��s nn rhr r� �:•rcr !�c ;"rr r�,m�..'r��nj�) 1 uC'Cat �v0 1. ]. HEGPIENT'S �CCES51f)MNC EPA=600L4=84-04�..-- ---�--�..------------------ -- P�3H 3 ?60 4% J. a��� �E a�u 5u8T�t�E ` 5 REPOA7 O47E � Analytical Method f�r Determin��tion of Asbestos Fibers in Water . .�VTHJR�SI � Eric J. Chatfield and P•1. Jane Dillon ) �ERFORh1�NG Or1G4N124TION NAME ANO AODRESS Department of Applied Physics Ontaric Research Foundation Sheridan Park Research Corrmunity Mississauga, Jntario, Canada L5K 1B3 12. yPQN50R�NG AGENC�' VAV1E AND 4DORE55 Environmental Research Laboratory--Athens GA Office of Research and Development U.S. Environme►ital Protecti�n A9ency Athens, Georgia 30613 15. SUPF�EMENT.>RY NC�TEs Pi RFORMING OA��nN124TiON C��DE PERFORMING OR�iAN12ATION REPORT h0. 10. PROGRA�t EIEh CBNCIA ,11. CONTRACT'Gaa 168-03-2717 1�, TYPE OF REPORT AND PER100 COVERED Final, 10/78-9/31 14. SPONSORInIG AGENCV CODE EPa!000�oi An analytical method for measurement of asbestos fiber concentration in water samples is described. Initially, the water sample is treated with ozone gas and ultraviolet light to oxidize suspended organic materials. The water sample is then filtered through, a 0.1, r�icrometer pore siz� capillary-pore polycarbonate filter, after which the filt�r i� prepared by carbon extraction replication for examination in a transmis�ion electron microscope (TEM}, Fibers ar� classified using selected area electron diffraction and energy dispersive X-ray analysis. Measurement of characteristic features on a recorded and calibrated selected area electron diffrac- tion pattern is specified for precise ic+entification of chrysotile. Quantitative determination of the chemical composition, and quantitative interpretation of at leas one calibrated zone azis selected area diffraction pattern are specified for precise identification of amphibole. Amphibole identif�catien procedures and generation of the standard reporting format specified for the fiber count resii'ts are achieved using two computer programs �that are integral to the analytical method. �, KEV WORDS ANO DOCUMENT ANAIYSi$ _ �_ __ . -~_ _ DESCRIPTOpS _ _, _ b.IOENTIfiERS/OPEN ENOEO TEFMS �. COSATI I�li•1�1;(�rt�up IYq, U�:,TRIBUT�ON STA?EMENT RELEASE TO PUBLIC �` EPA Form 2220•1 (9•7�� i i�p.riU � 21 UNC�.ASSIFIED 20. SECURiTY CLASS /Thit paRt1 UNCIASSIFIED 1 OF PA 277 ICE �„ . . - -- - -- -- �- - -. .�. � .. . . e��c. ��> ,, : - . ..� �:� i �,y dl - COr�ikul r�uMr�tk: U2 u�bu \� � ) a�l - ACCt55I��� ��U�ahEFt; ..... l ...................P8b3-2bUv7l d3 - COLLECiiO�v CUUE: 5 do - r�dr�aGt.'�tE.+T CuVE: WG . f17 • F��(JI.tSS a�T �t; CU: UU ti1A•KEGISiHAT1uP� FEE: OOuOu de - �K��ouC r t•,ar�a�t�r; H 69 • kECE1Nr irrE: i d9a-�ua�•� UuE Uu�: t�l�- I�tA�vS��l'fIU��: tiv 81�A-JUNE/Pk1uR/SUF�EFt: ktll- RETUrtN$; U BI2d-RE,TUF�i� UAIE: ci13- F'KuCE55I���; � hiu• Pai. P�1E��ila�: u ' d17- FJ�2.'•�/PrtICE: 12111 r 81 Ei- Ar,�v�U��CE : I 1 � 1 biy- pud�icn�tu��-1: u�s�b �2u- PUIiLICA1IUrv-�: b21• �I�•�ITaTIu�:: U 823- PC dI�v: OOU B2u� Sf�Ch; OODU Ii2�Q-STuCK TYf't CODES: t� 625- PaGtS/SMtEtS; UU'l76 li2o- f'C F'K 1 Ct CUJt : A 1 S — ti27- uU''ESTIC PHt�E; UuuU�Ou b28- FOREIG�� PRICE: OOODU00 ti24- AC1IJ�� CUUES: bp d33- �a�� Pk10E CU�t: AU1 t�3a- �u;��t�TIG r'K1GE: OOOuODU d35• FUREIG�� PitlCE: OOOU000 b3b- aCTi��� (:O�ES: MA it37• rcEL�ASaHiI,! f i GU: C • d33- h:F �r�I:�i; q tssy- AuUI f i�",a� 1�vFu: n • nU�• PHI��1 NC: n d4 � - f�C DUF-s �.. . •±- �_.�� 64�• SuuKGt. UkUtFt; n By2A-GE���EnaTt RU�: � c42ci-SuNNi.lErt sHC CD: � DISCLAIMER , The ififormation in this document ha5 been funded wholly or in part by the United States Environmental Protection Agency under Contract No. 68-03-2117 to Ontario Research Foundation. It has been subject to the Agency's peer and administrative review, and it has been approved for publication as an EPA document. Mention ol trade names or conunercial products does not constitute endorsement or recommen- dation for us�. ii ..�►---- — _ .. _ . � FOREWORD Nearly every phase of environmental protection depends on a capability to identify and measure specific pollutants in the environment. �s part of this Laboratory's research on the occurrence, movement, transformation, impact, and control of environmental contaminants, the ,analytical Chemistry Branch develops and assesses new techniques for identifying and measuring chemical constituents of water and soil. A 3-year study was conducted to develop improvements in the analytical method for determination of asbestos fiber concent.rations in water samples. The research produced an improved sample preparation and analysis method- ology, a rapid screen�ng technique to reduce analysis cost, and a new rererence analytical method for asbestos in water. The analytical method for de�ermining asbestos fibers in water is perceived as representing the curre,it state-of-the-art. William T. Donaldson Acting Director Environmental Research Laboratory Athens, Georgia iii � PREFACE � The Preliminary interim Method for Determining Asbestos in Water was issued by the U.S. Environmental Protection Aqency's Environmental Research Laboratory in Athens, Georgia. 7h2 method was based on filtration of the water sample through a sub-micrometer pore size membrane filter, followed by preparation of the filter for direct examination and counting of the fibers in a transmission electron microscope. Two alternative techniques were specified: one in which a cellulose ester filter was prepared by dissolution in a condensation washer; and another known as the carbon-coated NucleporeR techn�que which used a polycarbonate fil�er. In January 1980 th� method was revised (EPA-b00/4-80-005) to eliminate the condensation washer ��+?roach, and d suggested statistical treatment of the fiber count data was incorporated. The analytical me�hod published here is a furiher refinement oT tha_ revised interim method. Major additions include the introduction of ozone-ultraviolet light oxidation prior to filtration, complete specification of techniques to be used for fiber identification and fiber counting rules, and incorporation of reference standard dispersions. A standardized reporting format has also been introduced. The major deletion is �he low temperature ashing technique for samples high in organic material content; ashing is not required for the analysis of drinking water and drinking water supplies when samples are treated using thf ozone-ultraviolet oxidation techniGue. The "field-of-view" approach for examination also has been deleted from the method. If a sampte is too heavily loaded for examination of entire grid openings� d more reliable result is obtained by preparation of a new fi?ter using a smaller volume of water. iv aBSTRACT .an analytical nethod for measurement of asbestos fiber concentration in water samples is described. Initially, the water sample is treated witn ozone gas and �ltraviolet light to oxidize suspended organic materiais. The water sample is then filtered through a 0.1 �m porP size capillary-pore polycarbonate filter, after which the filter is prepared by carbon extraction replication for examination in a transmission electron microscope ;TEM). Fibers are classified using selected area electron diffraction (SAE01 anJ energy dispersive X-ray anal�sis {EOXA). ��easurement of characteristic features• on a recorded and calibrated SAED pattern is specified for precise identification of chrysotile. Quantitative determinatiun of the chemicat composition, and quantitative interpretation of at least one cal;brated zone axis SAED pattern are specified for precise identification of ampnibole. Amphibole identification procedures and generation of the standard reporting format specified for th� fiber count results are achieved using two cem�uter programs which are integral to the analytical method, This analytical method is a further developmQnt of �he interim nethod issued in 198C, and incorporates results of research performed under Contract 68-03-2717 under sponsorship of the U.S. Environmental Protection AQency. This report covers a period from October 1978 to September 19�1 and the work was cc�plzted as of September 1981. � � CONTENiS FOREWORD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i i i PREFACE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i v A@STRACT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v FIGURES ................................ x TABLES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi 1. Z. 3. 4. 5. 6. SCOPE AND APPLICATION . . . . . . . . . . . . . . . . . . . . SUMMARY OF METHOD . . . . . . . . . . . . . . oEFtNtTIONS, UNITS ANO A66REVIATIONS� . . . . . . : . . . . . . 3.1 Definitions . . . . . . . . . . . . . . . . . . . . 3.2 Units . . . . . . . . . . . . . . . . . . . . . 3.3 Abbreviations . . . . . . . . . . . . . . . . . . . EQUIPMEN7 AND APPARATUS . . . . . . . . . . . . . . . . 4.I Specimen Preparation�Laboratory . . . . . . . . . . 4.2 Instrumentation Requirements . . . . . . . . . . 4,2.1 Transmission Electron�Microscope . . . . . 4.2.2 Energy �ispersive X-ray Analyzer ..... 4,2.3 Computer . . . . . . . . . . . . . . . . 4.2.4 Vacuum Evaporator . . . . . . . . . . . . . 4.2.5 Ozone Generator . . . . . . . . . . . . . 4.3 Apparatus, Supplies and Reagents . . . . . . . . . . SAMPI.E COILECTION AND PRESERVATION . . . . . . . . . . . . . . 5.1 Sampie Container . . . . . . . . . . . . . . . . . . 5.2 Sample Collection . . . . . . . . . . . . . . . . . 5.3 Quantity of Sample . . . . . . . . . . . . . . . 5.4 Sample Preservation and Storage . . . . . . . . . . PROCEDURE . . . . . . . . . . . . . . . � 6.1 Cleantiness and Contamination Control . . . . . . . 6.2 Oxidatfon af Organics . . . . . . . . . . . . . . . 6.3 Filtration . . . . . . . . . . . . . . . . . . . . 6.3.1 General � . . . . . . . . . . . . . . . . 6.3.2 Filtration Procedure . . . . . . . . . . 6.4 Preparation af Electron Microscope�Grids ...... 6.4.1 Preparation of Jaffe Washer .. ... 6.4.2 Selec�ion of FiitPr area for Carbon�Coating. 6.4,3 Carbon Coatinq of the Nucleoore Filter ... 6.4.4 Tran;fer of the Filter to Electron Microscope Grids . . . . . . . . . . . . 6.5 Examination by Electron Microscop�/ . . . . . . . 6.5.1 Microscope Aiignment and Magnification Calibration . . . . . . . . . . . . . . vii �� 1 1 2 a 5 5 6 6 8 8 9 9 15 15 16 16 16 17 11 17 20 20 22 23 24 24 26 27 28 28 7. 10. 6.5.2 Calibration of EDXA System 6.5.3 Grid Preparation Acceptability � � � � 6.5.4 ?rocedure for fiber CounYinq � � � � � 6.5.5 Estimation of Mass Concentration � fi.6 Fiber Counting Criteria . . . . . � � � b.6.1 Fiber Counting Method . , � � � � � � 6.6.2 Fibers �hich Tour.h Grid Bars � . � � � � � � 6.6,3 Fibers Which Extend Outs�de the Field�of � `Jiew . . . . . 6.6.4 Fibers with Stepoed Sides . . � � � � � 6.6.5 Fiber Bundles . � � � � � � 6.6.6 Aggreqates of Randomly Oriented�Fihers .�� 6.6.7 Fibers Attached to Non-Fibrous Debris �� 6.7 Fiber ldentification Pr�cedures . � � 6.7.1 General , , , � � � � � � � � � 6.7.2 SAED and ��XA�Techniques . . . � � � � � 6.7.3 Analysis of Fiber :dentification Data. •�� 6.7.4 Fiber Classification Categories � � � 6.7.5 ='rocedure for Classification of Fibers '�lith� Tubular Morphology, Suspected to he Chrysotile . . . . . . 6.7,6 Procedure for Classification of Fibers . � Without Tubular MorDhology, Suspected to be Amphihole . , , , 6.8 Blank and Control Oeterminations . � � � � � � � 6.8.1 Blank Determinations . . � � � � � � � � � 6.8.2 Control Samples . . . � � � � � � � � � CALCULP.TION OF RESULTS . . . . � � � � � � � � � � � 7.� Test for Unifor�nity of Fiber.0eposit•on Electron. � Microscope Grids . . . . i.2 Calculation of the Hean and Confidence.:nterval of� � the Fiber Concentration 7.3 Estimated Mass Concentration� . � � � � � � � � � � � 7.4 Fiber length, '�lidth, �tass and Aspect�Ratio � � � � � Distributions . . . 7.4.1 Fiber Length Cumulative.,vumber Oistribution. 7.4.2 Fiber Width Cumulative Number Distribution . 7.4.3 Fiber Length Cumulative Mass Distr9bution 7.4.4 Fiber Asaect Ratio Cumulative Number � Distribution . . 7.4.5 Fiber �1ass Cumulative P�umber Distribution � 7.5 ;ndex of Fibrosity ' REPORTING � � � � � � � ' ' ' ' ' ' ' ' ' ' IIMITATIONS OF�ACCURACY � � � , � � � � � � � � � � � � � ' ' ' 9.1 Errors and Limitations.of Identification� ������ 9.2 Obscuration . . . � � � ' � ' 9.3 Inadequate Dispersion � . . . . � � � � � � � � � � 9.4 Contamination , . � ' � � � � � ' � ' ' 9. 5 Freez i ng . . . . . . . . . . . . . . . . . . . . PRECISION AND ACCURACY� . . . � � � � � � � ' ' ' ' ' ' 10.2 Genrral . . . . . . . . . . . . . . . . . . . . . . 10.2 Precisi,r� . . . . . . . . . . . . . . . . . . . . . 0 viii 29 ?0 "sl 34 35 35 35 36 36 37 37 33 ?a 38 39 43 45 4S 50 54 54 54 55 55 56 59 61 61 62 62 62 53 63 E3 65 55 66 66 66 66 67 67 67 � 10.2.1 Intra-Laboratory Comparison Using Environmental Water Sources . . • • 67 10.2.2 Inter-Laboratory Comparison of Filters Prepared Using Standard Dispersions and Environmental '�ater Sources . . . . 67 10.3 Accuracy . . . . . . . . . . . . . . . . . . . 11 1C.3.1 Intra- and Inter-Laboratory Comparison of Standard Oispersions of Asbestos F i bers . . . . . . . . . . . . . . . . . 71 SELECTEO BI6l.I0GRAPHY . . . . . . . . . . . . . . . . . . . . . . . 74 APPENDIX A- TEST OATA ANO COMPUTER LISTtNGS - FOR FIBER IDENTIFICATION , . . , . . . . . • • • • • » APPENOtX 8- TEST DATA ANO COMPUTER LISTINGS FOR OATA PROCESSIPJG ANO REP4RTING. . . . . . . . . . 176 ix Nurrber 1. 2. 4, SA. 56. 6. 7. 8. 9. 10. 11. 12. 13. 14, 15. 16A. 168, 17. I8. s FIGURES ?aqe Calibration �tarkinqs on TcM Viewing Screen . . . . . . . . . . . 7 Diagram of Ozone—UV Equipment . . 18 Ozone—U'J Oxidation of Water Samples �n Glass Bottles• � �� 19 'uclepore Oissolution Technique . . . . . . . . . . . . . � � � �� Jaffe '�Jasher Oesign . . . . . . . . . � � � �5 Jaffe �iasher i n Use . . . . . . . . . . . � � � � � � � 25 Condensation '�Jasher . , , , , , , , , � � � � � ' ' ' ' �3 Sheet For Recording Water Samole•Data . . . . � � � � � 32 Sheet For Recording Fiber Classificatio�i and MeaS��rement�Data .� 33 Counting of Fibers Which Overlap Grid Bars .... � 35 Counting of Fibers Which Ext2nd Outside the Field o"�View . �� 36 Counting and Measurement of Fiber Bundles ... 37 Counting of Fiber Agqregates � � � � � . � � � �� Counting and Measurement of Fibers�Attached to•Von—Fibrous ��� Oebris . . , 38 ��leasurement of•Zone Axis�SAED Patterns. . . . . . � � � � • 41 Classificat?on Chart for Fiher '�lith Tubular '�orphology ,,,,, 47 TEM Microqraph of Chrysotile Fibril, showing Morphology ...,. 49 TEM Mi crogra�h of U ICC Canad i an Chr•ysot i 1 e F i her af ter ther;na t Deqradation by Electron Seam Irradiation ..., a9 SAEO Pattern of Chrysotile Fiber �Nith Oi3gnostic Features l.abelled.50 Ciassification Chart for Fiber '�1ith�ut Tubular ��lorphology .... S? x � � ye Number 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. TABLES Paoe Limitation of Analyticai Sensitivity by Volume of"Water Sample Filtered . . . . . . . . . . . . . . . . . . . . . . . . 21 Siiicate Mineral�Standards . . . . . • • • • • • • 29 Classification of Fibers With iubular '�orphology . . . . . . . . 46 Classification of Fibers Without 7ubular ��orphology ....•. 46 Levels of Analysis for Amphibole . . . . . . . . 53 Intra-Laboratory Comparison of Environmental�Water�Samples ... 68 Inter-laboratory Comparison: Standard Dispersions . . . . . . . 69 Inter-laboratory Comparison: EnvironmentaT Water Samples ... 7� Inter- ar.d Intra-Laboratory Comparison: Chrysotile ...... 72 Inter- and Intra-Laboratory Comparison: CroCidolite ...... 73 xi ANaLYTICAL METN00 FOR OETERMINAtION OF ASBESTOS FIBERS IN '�►ATER l. SCOPE AND APPLICATION �� 1.1 This method is applicable to drinking water and drinking water suoplies, and should he used when the bes? available analytical procedure is required. 1.2 The method determines the numerical concentration of asbestos fibers, Lhe length and width of each fiber, and the estimated mass Concentration of asbestos in the water. Fiber size and aspect ratio distributions are also determined. • 1.3 The method permits, if required, identification of all mineral fibers found in water. In particular, chrysotile can be distinguished from the amphiboles, and fibers of specific amphiboles can be identified. 1.4 The analyti.:al sensitivity which can be achieved depends primarily on the amount of other particulate matter which is present in the sample. This limits the proportion of the sample which can be mounted for examination in the electron microscope. In drinkina water which meets the �'�1`,JA turhidity criterion of 0.1 �VTJ, an � asbestos concentration of 0.01 miilion fibers per liter (�1F�) can be detected. The contamination level in ti�e laboratory environment may degrade the sensitivity. 7he analytical sensitivity for the determination of mass concentration is a`unction of the preceding parameters and also depends on the si=e distribution of the fibers. In Tow turbidity drinking �Hater the analytical sensitivity is usualTy of the order of 0.1 nanogram per liter (ng/L). 1.5 It is beyond the scope of this document to provide detailed instruction in electron microscopy, electron diffraction, crystaTlogranhy or X—ray fluorescence techniques. It is assumed. that those performing this analysis will be sufficiently knoNiedgeable in these fields to understand the soecialized techniques involved. 2. SUMMARY OF METH00 Water collected in a polyethyl�ne or glass container is treated with ozone and ultraviolet light to oxi�ize organic matter. After mild ultrasound treatment to dis�erse the `ibers uniformly, a�ncwn volume of the water is filtered through a 0.1 micMometer (��n �' ) pore size `IucleporeR polycarbonate filter. a carbon coati�g is then apniied in vacuum to the active surf ace of the filter. The carbon layer coats and retains in position the material which has been cotlected on the filter �: surface. A small portion of the carbon—coated filter is placed on an etectron microscope grid and the polycarbonate filter matP�ial is removed by dissolution in an organic soivent. The carbon film co.�tatning the original particulate, supported on the electron microscope grid, is then � � examined in a transmission electron microscope (TEM) at a magnification of about 20,000. In the TEM� selected area electron diffraction (SAE�) is used to examine the crystal structure of a fiber, and its elemental canposition is determined by energy dispersive X—ray analysis (EDXA). Fibers are classified accordi�g to the techniques which have been used to identify them. A simple �ode is used to record for each fiber the degree to which the identification attempt was successful. The fiber classification procedure �is based on successive inspection of the morphology, the selected area electron diffraction pattern, and the qualitative and quantitative energy dispersive X—ray analyses. Confirmation of the iderttification of chrysotile is only by quantitative SAED. anC confirmation of amphibole is only by quantitative EDXA and quantitative zone axis SAED. Several Tevels of analysis are specified, three for chrysotile and four for amphibole� defined by the most specific fiber classification to be attempted for all fibers. The procedure permits this target classificatian to be defined on the basis of previous kno�xledge, or lack of it, about the particular sample. Attempts are then made to raise the classification of all fibers to this target classification, and to record the degree of success in each case. rhe lengths and widths of all identified fibers are recorded. The number of fibers found on a known area of the microscooe sample, together with the equivalent volume of water `ilte►� d chrough this area, are used to calculate the fiber concentration in MFL. The mass concentration is �alculated in a similar manner by surtmation of the volume of the identified fibers, assuming their density to be that of the bulk material. �. OEFINITIONS, UNITS AND ABBREVIATIONS 3.1 Definitions Acicular — 7he shape shown by an extremely slender crystal with smali cross—sectional dimensions. Amphibole — A group of rock—forming ferromagnesian silicate minerals, closely related in crystal form and composition and having the general formula: A2_365{Si,AI}8Q2z(OH)2, - where A• Mq, Fe+2� Ca, Na or K, and B� Mg� Fe+z,Fe+3 � or A1. Some of these elements may also be substituted by Mn, Cr, Li, Pb, Ti or Zn. It is characterized by a cross—linked dovble chain of Si-0 tetrahedra with a silicon:oxygen ratio of 4:11, by columnar or fibrous prismatic crysta�s and by good prismatic cleavage in �, __ . ._. two directions parailel to the crystal faces and intersecting at angles of about 56° and 124°. Amphibole Asbestos - Amphibote in an asbestiform habit. �f� Analytical Sensitivity - The calculated concentration in �'� L equivalent to countinq of one fiber. � Asbestos - A commercial term applied to a group of silicate minerals that readily separate into thin, strong fibers that are flexible, heat resistant and chemically inert. Aspect Ratio - The ratio of length to w�dth in a particle. Camera length - The equivalent projection length betNeen the sample and its electron diffraction pattern, in the absence of lens action. Chrysotile - A minera] of the serpentine group: Mg3Si�05(OH)q, It is a highly fibrous, silky var�ety of serpent��e, and constitutps the most important type of asbestos. Cleavage - The breaking of a mineral along its crystallographic planes, thus reflecting crystal structure. Cleavage rragment - A fraqment of a crystal that is bounded by � cleavage faces. d-Spacing - The separation between identical adjacent and parallel planes of atoms in a crystal. Diatom - A microscopic, sinqle-celled ptant of the class Bacillariophyceae, which grows in both marine and fresh water. Diatoms secrete walls of silica, called frustules, in a great variety of forms. Electron Scattering Power - The extent to which a thin layer of a substance scatters electrons from their original path directions. Energy Oispersive X-ray Analysis - Measuremen*, of the energies and intensities of X-rays by use of a solid state detector and multichannel analyzer system. Eucentric - The condition when an object is placed Nith its center on a rotation ur tilting axis. Fibril - A single fiber, which cannot be separated into smaller v components without losing its fibro��s properties or appearances. � 3 xy £ � 0 Fiber - A particle which has parall?1 or stepped sides, �n aspect ratio equal to or yreater than 3:i, and is greater than 0.5 um in length. Fiber Aggregate - An assembly of randomly oriented fibers. Fiber Bundle - A fiber composed of parallel, smaller diameter fibers attached along their lengths. Habit - The characteristic crystal form or combination of forms of a mineral, including characteristic irregularities. Miller Index - A set of three or faur integer numbers �sed to specify the orientation of a crystallographic plane in relation to the crystal axes. Replication - A procedure in electron microscopy specimen preparation in which a thin copy� or replica, of a surface is made. Selected Area Electron Diffraction - A technique in electron microscopy in which the crystal structure of a sma]1 area of a sample may be examined. Serpentine - A roup of common rock-fo rtning minerats having the . formuia: �Mg,Fe)3 Si205(OH)4. Unopened Fiber - Large diameter asbestos fiber which has not been separated into its constituent fibrils. Zone Axis - That line or crystallographic direction through the center of a crystal which is parallel to the intersection edges of t�e r.rystal faces defining the crystal zone. 3.2 Units eV g/cm3 - eTectron volt - grams per cubic centimeter kV - kilavott ug/L - mic�ograms per liter (10-6 grams per liter} um - micrometer (1�r6 meter) MFL - Million Fibers per Liter ng/L - nanograms per liter (10-9 grams per liter} nm - nanometer (10-9 meter) f� 4 • ..._ . . . . . , .. . . ..- . .,. .. _ __.- _ . . � . ._ NTU — Yephelometric Turbi�iity Unit PPm — parts per million 3.3 Abbreviations `� ,. AWWA — American Water Works Association EDXA — Energy Oispersive X—ray Analysis '� HEPA — High Efficiency Particle Absolute SAEO — Selected Area Electron Oiffraction SEM � — Scanning Flectron Microscope STEM — Scanning Transmission Electron �HicroScepe TEM — Transmission Electron Microscope UICC — Union Internationale Contre le Cancer (Tnternatio�al Union Aqainst Cancer) JV — Ultraviolet 4. EQUIPMENT AND APPARA?US 4.1 Specimen Preparation laboratory Asbestos, oarticularly chrysotile� �s present in small quantities in practically all laboratory reagents. Many buildinq materials also contain significant amounts of asDestos or other mineral fibers which may interfere with analysis. It is therefore essential that all specimen preparation steps be performed in an environment where contamination of the sample is minimized. The primary requirement of the sample preparation laboratory is that a blank determination using known fiber—free water must yield a result which will meet the requirements specified in Section 6.8.1. Preparation of samples should be carried out only af ter acceptable blank values have been demonstrated. The sample preparation areas should be a separate clean room with no asbestos—containing materials such as flooring, ceilinq tiles, insulation and heat—resistant products. The work surfaces should be stainless steel or plastic—laminate. The room should be operated under oositive pressure and have absolute (HEP.4) filters� . electrostatic precipitation, o►� eauivalent, in the air supply, A laminar flow hood is recommended for sample manipulation. It is recommended that a supply of disposable labor�tory coats and � disposable overshoes be obtained to be worn in th�� ctean room. This will reduce the levels of�dust� and particularly asbestos, which might be transferred inadvertently by the operator into the � • m� � d � clean area. Normal electrical and water services are required. An �. air extract (fume hood) is required to remove surplus ozone from the area near the ozone 9enerator. 4.2 Instrumentation Requirements � 4.2.1 Transmission Ele� cron Microscope A transmission electron microscope having�an accelerat:ng potential of a minimum of 80 kV, a resolution better than 1.0 nm, and a magnification range of 300 to 100,000 is required. The ability to obtain a direct screen magnifi— cation of at lcast 20,000 is necessary. An overall magnification of about 100,000 is necessary for inspection of fiber morphology; this magnification may be obtained by supplementary optical enlargement of the screen image by usa of a binocular if it cannot be obtained directly. It is also required that the viewing screen be calibrated.(as _ shown in figure 1) w9th concentric circles and a mitlimeter scale such that the lengths and widths of fiber images down to 1 mn width can be measured in increments of 1 mm. ...� For Bragg anqles less than 0.01 radians the instrument must ' be capable of perfarmi�g selected area electron diffraction from an area of 0.6 um or �ess, selected from an in—focus image at a screen ma�nification of 20,000. This perform— ance requirement defines the minimum separation between particles at which independent diffraction patterns can be � obtained from each. The capability of a particular instrument may nor�nally be calculated using the following relationship: A = � (M + 2000 CS93)2 . where: A � Effective SAED area in �m2 D � Diameter of SAED aperture in um M � Magnification of objective lens �S • Objective lens spherical aberration coefficient im m� ' s • Maximum Bragg angle in radians Aithough almost all instruments of current manufacture �neet these requireme�ts, many otder instruments which are still in service do not. It is obviously not possibte to reduce the area of analysis indefinitely by use of apertures � , � 1 e � e � s I � � �`� � � , � '�� ����� �� �'� '�� \�\�'� `�� � � . \� `, \, \�\ �`, �'', '',, �, `�� �� � � ` \ � � ., `,, ; ', '� , �'� . `�� 1 �1 \ `\ \ l, ` � �, .+ , ` ` • �� , • i ! � �i I i �'I ' 1� i ; i i i i i z I �' i, i., a� � � � � ' ' 1 � ' , � ; , �` �% ; � �� � : � j' .� f . . � ; /� % �,' �/ j I '� % %, /t �, / / / �� % I � � �/ / �� .� l �� � Figure 1. Calibration Markings on TEM �liewing Screen. 7 � v 4 ... . . . . . � - � � .. . ._ .. - � smaller in diameter than manufacturer, since there � imposed by the spherical. �, objective lens. those sAecified by Che is a fundamentai limitation aberration coefficient af the If zone axis SAED analyses are to be performed, it is required that the electron microscope be fitted with a goniameter stage which permits either a 360° rotation combined with tilting thro�gF� at lea�t +30° to -30�, or tilting throuqh at least +30 to -30 around two perpendicular axes in the plane of the sample. The work is greatty facilttated if the goniometer permits eucentric tilting. It is also essentiai that the electron microscope have an illumination and condenser lens system capable cf for�ninq an electron probe smaller than 100 nm in diameter. Use of an anti-contamination trap around the specimen is recommended if the required instrumental performance i5 to be obtained. 4.2.2 Energy Dispersive X-ray 'Analyzer An energy dispersive X-ray analyzer is required. Since the performance of individual combinations of equipment is critically dependent on a number of geometrical factors, the req��ired performance of the combination of electron microscope and X-ray analyzer is specified in terms of the measured X-ray intensity f�om a small diameter fiber, using a known electron beam diameter. X-ray detectors are generally ieast sensitive in the low energy region, and so measurement of sodium in crocidoli�e is selected as the performance criterion. The combination of electron microscope and X-ray analyzer must yield a background- subtracted NaKa peak integral count rate of more than 1 count per seconG (cps) from a 50 nm diameter fiber of UICC crocidolite irradiated by a lu0 ^m diameter electron probe at an accelerating potential of 80 kY. The eq��ivalent peaklbackground ratio should exceed 1.0. The EOXA equipment must provide the means for sub�raction of the background, identification of elemental oeaks, and calculation of net Peak areas. 4.2.3 Computer Many repetitive n��merical calculations are necassary, and these can be perfarmed conveniently by relatively simple cemputer Nrograms. For analyscs of zone axis diffraction pattern measurements, a computer facility with minimum available memory of 64K words is reauired to accommodate 0 -- � - � � ... � , . _ . ..--_-.-.�...,_._,. ._..._.�,.,--�.-_.,, the more complex programs involved. Suggested orcgram listings for standardized daLa reporting and fiber identification routines are inclu�2d as part of this analytic.31 procedure. (Appendices A and 6). 4.2:4 Vacuum Evaporator �� A vacuum4evaporator capable of producing a vacuum better than 10— Torr (0.013 Pa) is required for vacuum deposition of carbon on to the potycarbonate filters. A sample holder is desirable which allows a 51 x 75 mm glass microscope slide to be tilted and ro�ated during the coating procedure. Use of a?iquid nitrogen cold trap abovA the diffusion pur�p will minimize the possibility �f contam�nation of the filter surfaces by oil from the pumping syst�m. The vacuum evapo�ator may also be used for deposition of the thin film of aold� or other reference material, required on e?ectron microscope samples for calibration of electron diffraction patterns. For gold deposition, a sputter coater may allow better control of the process, and is therefore recommended. 4.2.5 Ozor,e Generator An�ozone generator, in combination w�th ultraviolet light irradiation, is used for the oxidation of organic material in water samples. This procedure �s necessary on a11 water samples. The generator should be capable of oenerating at least 400 g of ozone p��r day at a concentration of at least 1� by weight when sup•�lied wi�h dry oxygen, ihe ozone generator Model 6L-1 (PCI Ozone Corporation, 1 Fairfietd Crescent, West Ca;dwe'1, New Jersey 07006) or equivalent has been found to meet the requirements of this analytical technique. . 4.3 Apparatus, Supplies and Reagents 4.3.1 Gas Supply to Ozone Generator The ozone generator ca� be supolied by either compressed air or oxygen. The input gas must be regulated to the pressure specified by the generator manufacturer. It is recommended that �xygen be provided in order to reduce the possibility of acid formation in the sample. 4.3.2 Gas—Line Orying Tube The ozone generator operates more efficiently when supplied with dry axygen. An in—tine drying tube. filled with a desiccant, followed by a 0.2 ��m pore size polytetra— f)uoroethylene filter to prevent particulate from the desiccant entering the ozone generator is recorr,mended. w , . . . - ---�-....�,_.,_ � A Stainlzss st?el pressure filtration assembly (�1illipore Corpor�tion, Bedford MA 01730, Cat. No. XX40 047 00) with a 0.2 �:m pore size FluoroporeR filter (Hillipore Corporation, "� Cat. No. FGIP 041 00) in the normal filter posit�on and silica gel in the reservoir have been found to be _ . satisfactory for this purpose. ;� 4.3.3 In-Line Gas Fittration Assembly _ A filter is placed in the ozone line immediately before the qas enters the sam�le. A 25 mm stainl�ss steel gas line filter holder (Millipore Corporation, Cat. No. XX40 025 00) or equivalent with a 0.2 um pore size Fluoropore filter (Millipore Carporation, Cat. No. FGLP 025 00) or equivalent is used in each ozone supply line to ensurP that the ozone entering the sample is particle-free. 4.3.4 Ultraviolet lamp A submersible short wavelenqth (254 nm) ultraviolet lamp is required for the ozone-UV oxid�tiun treatment of water samples. A 6 inch Pen-RayR ultraviolet lamp (Part No. 90-0004-I1) and power supply model SCT-4 (Ultra-Violet Products Inc., 5100 '+�alnut Grove Avenue, San Gabriel, California 91778) or equivalent have been found to meet the requirements of this analytical technique, 4.3.5 Source of Known Fiber-�ree Water For blank determinations, final v+ashing of analytical equipment, and dilution of some samples, a source of water which is free of both particles and fibers is required. Fresh double-distflled water from a glass distillation apparatus (ME6A-PURET''� manufactured by Corning and available from all authorized Corning Laboratory Supply Dealers) or equivalent is preferable, and has been found to meet thiS requirement. De-ionized water, filtered through a 0.1 um pore size yuclepore polycarbonate filter�has also been found to be satisfactory, but the filtration 3ssembly itself tends to contribute some oarticles to �he filtrate. 4.3.6 Filtration Apparatus The water sample is filtered through a membrane filter of either 41 mm diameter or 25 �Txn diameter. The filtration assembly should be chosen to suit the size of filter in r_ use. A glass frit support is required in order to obtain a uniform deposit on the filter. The reservoir must be easily cleaned in order to prevent sample cross- - contamination. A 47 rrm analytical filter holder (Millipore Corporation, Cat. ��o. XX10 047 00) or a 25 mm analytical filter holder (Millipore Corporation, Cat. No; XX10 025 00) 10 ..�.r �. .� .. or equivalent has been found to be suitable. `�hen us�ng the larger diameter equipment it is necessary to filter proportionately larger volumes of water. 4,3.7 Filtration Manifold 4.3.8 When a number of samples are to fi7tration units can be operated singie vac�um source by using a manifold (Miltipo�e Corporation, equivaleni. The manifold should each port to be opened or closed Vacuum Pump be filtered, several simultaneously from a mul�iple port filtration Cat. No. XX26 047 35) or include valves to permit independently. A pump is required to provide a vacuum of 20 kPa for the filtration of water samples. A water jet pump (Edwards Nigh Vacuum Inc., Grand Island, NY 14072, Cat. No, C1-0046-01-000-female connection or O1-0039-01-000-male connection) or equivalent has been found to provide sufficient vacuum for a 3-port filtration manifold and also incorporates a non-return valve to prevent back-streaming. 4.3.9 Membrane Fiiters The diameters of the membrane filters should be matched to the diameters of the filtration apoaratus in use. For filtration of water sarrples, two types of filters are required: - polycarbonate �apillary-pore membrane filters� 0.1 �m pore size (NuclFpore Corooration, 7035 Commerce Circle, Pleasanton, California 94566) or equivalent, are used to collect the suspended material•from a water sample. mixed esters of cellulose mem.brane filters, 0.45 um pore size 7ype HA (Millipore Corporation� Bedford, A1A OI730) or epuivalent, are used as a support filter placed between the glass frit of the filtration apparatus and the polycarbonate filter. 4.3.10 Jaffe '�lasher A Jaffe Washer is used for dissolution of �Vuciepore fiiters. Several designs of JaFfe �ashE;� have been used which are modifications of the original design. Provided that the polycarbonate filter can be completely dissolved, and that the materials used.in the different designs of washer are demonstrably free of mineral fiber contamination, the precise design is not considered 11 H . _ .�.._._...�_ __. ._. _ . ._r____�__— --------- •- -��--- - - - - � ;-+�^� important. Because of recent changes in the formulation of Nuclepore polycarbonate filters which have degraded their � solubility in chloroform, a more complex dissolution '�j procedure may be required. The additional steps in the preparation are more easily completed if Lhe original _ washer design is followed. This original design is iilustrated �n Figure SA. Figure SB shows samples being placed on a Jaffe 5lasher oP this design. Alternatively, ` methylene chloride may be substituted for chloroform, but because this has a higher vapor pressure it is then necessary to ensure that the Jaffe Washer is tightly sealed to avoid exc2ssive evaporation. 4.3.11 Condensation Washer A condensation wash�r may be useful if TEM specimens are required more quickly than is possible if the Jaffe Washer is used alone to dissoive some oatches of Nuclepore polycarbonate filters. A condensation washer consists of a system Hith controlled heating, controlled refluxing� and a coid finger for holding the electron microscope sample �rids. Fiqure 6 shows one model of the condensation washer Cat. No. 16950, Ladd Research Industries, Inc,, P.O. Cox 901, Burlington, Vermont 05401} which has been found sat i sf actory. 4.3.12 Electron Microscope Grids Specimen grids of 200 mesh and 3 mn diameter are required in both copRer and goTd. The grid o�eninQs should be approximately 80 um square. The fiber count result obtained is pr000rtional to the �nean area of the openings examined. Therefore, it is important that an accurate measurement of the dimensions of each grid openir,g can be obtained. Since there is a wide range of quality in the avaitable copper specimen grids, these should be examined carefuily to establlsh the degree of uniformity of beth the grid openings and the grid bars. Copper speci�nen grids Cat. No. SPi �302CC and 3020T, SPI Supplies Oivi�ion of Structure Probe, Inc., P.O. Box 342, West Chester, PA 19380, or equivalent, have been feund to meet the requiremenLs. In addition, these grids have a mark at the center openin�. ihis reference can be used to indicate the location of openings which have been examined. Alternatively, finder grids may be substituted if re-examination of specific grid openings is to be required. Gold specimen grid� Cat. No: 21b12, Ernest F. FutTam, Inc., P.O. 8ox 444, Schenectady, N.Y. 12301, or equivalent�, have been found t� meet the requirements for gold grids. 12 4.3.13 Ultrasonic Bath An ultrasonic bath is requ�red `or disAersinq particu�a�e in sample containers and for general cleaning of equipment. The size of unit se�ected is unimportant, and should be related to the volume of work in proaress. Bransonic �4ode1 8-52 (Branson Cieaning Fquipment Company, Parrott Drive, Shelton Connecticut 06a84) has a pc�yer of 200 watts at a frequency of 5Q kHz and has been found to meet the requirements. 4.3.14 Carbon Rod Electrodes 4.3.15 4.3.16 Spectrochemically pure carbon rods are required for use in the vacuum evaporator during carbon coating of filters. Type aGKSP, National Spectroscopic Electrodes, manufactured by Union Carbide, or equivalent, have beer found to �eet the requirements. Carbon Rod Sharpener This device is used to sharpen the carbon rods to a neck of 3.6 mm long ar,d 1.0 mm diameter. The use of necked rods, or equivalent, allows the carbon layer to be apptied with � minimum of h�eating of the oolycarbonate membrane. The ;harpener, Cat. No. 1204, Ernest F, Fuilam, Inc., Schenectady, N.Y. 12301, or equivalent, mePts the requirements. Standards a) Reference Standard Fiber Suspensions. Glass amooules of stable concentrated chrysotile or a�ahibole fiber dispersions, {Electron Optical Laboratory, Ontario Research �ound�tion, Sheridan Park, �1�ssissauga, Ontario, Canada LSK 183) can be used to establish quality assurance in analyticai programs. The refarence suspensi�ns of known mass and numerical fiber concentretions are used to generate control samples for inclusion in anatytical programs. b) �eference Silicate Mineral Standards on TE��1 Grids. For calibration of the EDXA system, reference silicate mineral standards are reouired (Electron Optical Laboratory, Ontari� Research �ounda:ion, Sheridan Park, Mississauga, Ontario, Canada LS!C 183). c) Asbestos Butk Material. Chrysotile (Canadian!, Chrysotile (Rhodesian), Crocidolite, Amosite. UICC (Union Internationale Contre le Cancer) Standards. Available from �uke Standards Ccm�any, 445 Sherman Avenue� Palo Alto, CA 9a306. 13 4.3.17 Carbon Grating Replica A carbon grating replica with about 2000 parallel lines ��' oer rtm (Cat. No. 10020, Ernest F. �ul�am, Inc., Schenectady, N.Y. 12301) or equivalent is required for calibration of the maqnification of the TEM. �- 4.3.18 Chloroform Spectro rade chtorofo�-m, distilled in glass {vreserved Nith lA (v/v� ethanol, Burdick 3 Jackson Laboratories Inc., Muskegon, Michiqan 49442) or equivalent, is required for the dissolution of the polycarbonate filters. 4.3.19 Petri Dishes Oisoosable plastic oetri dishes (Millipore Corp. Cat. No. PO 10 047 00) or eq�iv3lent, are useful for storage of Sample filters and �Ge�imen qrids. If charge build—up on these dishes is experienced, it has been found that rinsing them with a weak deterqent solution Nill reduce the problem. 4.3.20 Quartz PiPets Quartz pipets are used to bubble ozone through the liquid sample. These pipets are formed by heating quartz tubing and drav+ing it to a tip of approxima�ely 0.35 mn inside diameter. The pipet sh�uid be sufficientiy tong to reach within 1 inch of the bottom of the sample bottle, to create good mixing of the liquid during oxidation. 4.3.21 Mercuric Chloride Solution A 0.01 molar solution of inercuric chloride may be required for preservation of vrater samples. This is orepared by dissolving 2.71 g of reagent grade mercuric chloride in 100 ml of fiber-free water. 7he solution is then filtered tv+ice through the same 0.1 um pore size Nuclepore filter, using the filtratio� apparatus �escribed in Section 4.3.6 and a conventional filtration flask. 4.3.22 Routine Electron Microscopy Preparation Supplies Electron microscooy preparation supplies such as scalpets, disposable scaloel blades (curved cutting edge)� � douDle-sided adhesive tape, sharp point tweezers and soecimen scissors are required. These items are available from most EM supply houses. � 14 �_,�� _..__ _ . .. _ . _ . ...- .�.�. ._i1'oT.'j•� � ' _' ' ' ' '. . . _ _ ._ . .�+. . . .. .�,. -c.. � v-0 - .-.-., ._.....su Figure 3. Gzone-UV Oxidation of Water Samples in G9ass Bottles. The ozone supply line has been split into two lines to permit simultaneous oxidation of two samples. A valve and a filter holder are incorporated in each of the supply lines to the samples. An 1ir extract to r?move surplus ozone is required. If it is necessary to check that the ozene generator is functioning within the specffications, the output can be verified by normal chemical methods. A suitable technique is to bubble the ozone through a solution of potassium iodide and to titrate the displaced iodine with sodium thiosulfate solution, usinq starch as an indicator. 8efore the ozone-UV treatment, place each polyethylene or gtass bottle containing the water sample in the ultrasonic bath for a period of 15 minutes. Mark the level of the liquid in the sample bottle using a waterproof felt marlcer. The quartz pipets should be thoroughly washed before each use, and �nstalled on the ozone supply as indicated so that the tip is close to the bottem of the sample bottle. The UV lama is also thoroughly washed and then imnersed in the sample and switched on. At an ozone concentrativn of 4; in oxygen, treat each sample with about 1 liter/minute of gas for approximately 3 hours. At other ozone concentrations, adjust the oxidation time so that each sample receives about 10 grams of ozone. The qas flow rate should be 19 � M sufficient to produce a mixing action in the liquid but should not splash sampie out of the container. It is not easy to indicate when oxidation is complete, but this treatment as described has " been found to be adequate for all water samples so far handled. When oxidation is complete, remove the UV lamp and quartz pipet, re—cap the bottle and place it in the ultrasonic bath for a period of 15 minutes. This allows particulate released from the oxidized � organic materials and the container surfaces to be unifornly dispersed throughout the sample. The water level in the bottle may have fallen, duP to evaporation during the oxidation procedure. The toss of volume should be noted and can be accounted for if it is significant. The sample should be filtered irrmediately after it is removed from the ultrasonic bath. 6.3 Filtration 6.3.1 Generat The separation of suspended particulate by filtration of the sample through a membrane filter is a critical step in the analytical procedure. The objective is to produce a Nuclepore filter on which the suspe�ded solids from the sample are distributed uniformly, with a ninimum of overlappinq of particles. The volume to be filtered depends on the diameter of the filtration equipment in use, the total suspended solids content of the sample, and in some samples the volume depends on the fiber concentration present. Table 1 show5 the limitation of the analytical sen5itivity as a*unction of the volume of water filtered. In practice� it is usually found that the concentration of suspende� solids limits the filtration volume. The maximum particulate io�ding on the filter which can be tolerated is about 2� ug/cm , with an oqtimum value of about S uq/cm . Where the concentration of suspended solids is known, the maximum vo�����e which can be used may be estimated. Usually, however, nothing is known about the sample and the best procedure is to prepa�-e several filters using different volumes of the sample. It has been found that suitable filter samples display a faint celoration �f the surface, and with exper�ence over—loaded filters usually can be recognized. ihe determination of a suitabie volume to fitter is usually a matter of trial and error in the analysis of samptes of relatively low total suspended solids but high asbestos concentration. No attempt should be made to filter sam�le volumes ]ess than 10 mL for 25 rmn diameter equipment, and 50 mL for 47 mm diameter equipment. If smaller volumes are filtered 20 TABIE 1. LIMITaTION OF ANALYTICAI SENSITIVITY BY VOLUME OF WATFR SAh1PLE FILTERED " Volume Filtered (mL) � Analytical Sensitivityl UsingF2jtmm Diameter Using 47 mm3Diameter (Fibers�Liter) � 2 Filter 0. 1 0.6 1.5 x 10� � I 0.5 2.8 3.0 x 106 1.0 5.7 1.5 x 106 2.0 11 0.8 x 106 � 5.0 28 3.0 x 105 10 57 1.5 x 105 I ZS 1a2 6.0 x 104 50 Z85 3.0 x 104 100 570 1.5 x 104 1Concentration corresponding to 1 fiber detected in 20 grid openings of nominal 200 mesh grid (approximately $0 ;.m square grid ooenings) 2Assuming Active Filter Area of 1.99 cm2 � 3AsSuming Active Filter Area of 11.34 cm2 21 � �. it is difficult to ensure that a uniform deoosit of particulate wiil be obtained on the filter. Sampies of high solids content, or of high fiber• content, may require F" filtration of volumes less than these. Such samples should � be diluted with fiber-free •Mater so that the volumes _ filtered exceed the minima specified. Oilutions should be made by transferring a known volume of the sampte to a disposable plastic bea�cer and making up to a known volume `� with fiber-free water. The mixture should be stirred vigorously before sub-sampling takes place. 6.3.2 Filtration Procedure a) The sample must be filtered irrsmediately after the ozone-UV and ultrasonic bath treatment. tf for any reason the sample has been stored for �nore than a few hours after these treatments, it is recommended that ozone-UV oxidation be repeated for a short period of about 15 minutes, followed by an additior�al 15 minutes in the ultrasonic bath. • b) Assemble the filtration base and turn on the vacuum. The upper surface of the filtration base (both the glass frit and the ground mating surface) must be dry before the membrane filters are installed. Place a 0.45 �,�m pore size type HA Miliipore filter on the glass frit. If the filter appears to become wet by capillary ac`.ion on residual water in the glass frit it must be discarded and replaced by another filter. Place a 0.1 um pore size Nuclepore filter, shiny side up, on top af the Millipore filter. If the � Nuclepore filter becomes folded it must be ' discarded and replaced. The mating surface of the reservoir component of the filtration apparatus (the funnel) should be dried by shaking off any surplus water and draining on paper tov,•el or tissue. The funnel should be positianed on the filters and firmly clamoed, taking care not to disturb the filters. The vacuum should not be released until the filtration has 5een completed. It is necessary to comnent on the use of filtration equipment which is still wet after washing, Since improper �rocedures at this point can very 5eriously compromise the results. If the qlass frit is wet when the Millipore filter is applied to it, capillary action will result in some areas of the Millipore filter structure being filled by water. When the Nuclepore filter is applied to the surface of the Millipore filter 22 and the vacuum is appiied, the differential pressure across the Mil)jpore filt?r will be insufficient to overcome the surface tension of the water in the filled areas. Thus no fittration wili take place through the correspondina areas of the PJucla�ore filter, and a gros5ly non-uniform deposit of particulate �ill be obtained. c) Add the required volume of sample water to the filtration funnel. Disposable plastic beakers and pipets provide a�eans of ineasurinq the required samp?? volume �Nithout introducing problems of sample cross-contamination. The reservoir may not be sufficiently large to accorr�nodate the total volume to be filtered. In this case more of the sample may be added d�ring the.filtration, but this should be done carefully and only when the rese�voir is more than half full. In this way the addition will not disturb or affect the uniformity of particulate already deposited on the Nuclepore filter. Do not rinse the sides of the funnel, and avoid other manipulations which may disturb the particulate deposit on the filter. d) �isa55emble the filtration unit, and transfer the �Vuclepore filter to a la�elled, clean petri dish. Since the i��uclepore filters are mora easily handled Nhile they are still wet, it is recommended that the strip of filter to be �sed for TE� samole preparation should be cut as described in Section 6.4.2 before the filter is dried. Place th� cover loose�y over the dish to limit any dep�sition of dust onto the filter. Dry the F'ilter under an infra-red heat lamp for a short time before closing the pe�ri dish completely. Discard the ��illipore filter. 6.4 Preparation of Electron ��icroscope Grids Preparation of the grid for examination in the electron n��croscope reQuires a high degree of man�,al dexterit� and is a critical step in the procedure. The ohjer.tive is to replicate the filter suriace by deposition of a carbon film and then to dissolve away the filter i*self with a minimum of particle move�ent and breakage of the carbon film. The filter dissolution procedure is iilus*.rated in Figure 4. 23 vpRti��ES —C,R80N � _ �� ' =poT NG ; �` � � °0�7Csa8GN:TE — ����R i Q . o 0 �IECTRQN �—' M�CAQSCOPE , :,Q�O 6.4.I � CHLOROFORM r— C4a80N � � �— �oi� Figure 4. Nuclepore OissoTution Technique Preparation of Jaffe '�lasher Prepare th� Jaffe 'rlasher as illustrated in Fiaure 5A. The stainless steel mesh is formed into a bridae slightly less than 1 cm high, and placed in a 10 cm diameter glass oetri dish with a tight fitting lid. A narrow strip of lens cleaning tissue is placed over the bridqe with each end of the tissue extending beyond the bridae to the base of the petri dish. The other dimensions of the stainless steel bridqe and the lenqth of the lens tissue are not cri*.ica1, but those specified in Figure 5A have been found to be satisfactory. After the assembly is complete, fill the petri dish with ch;loroform to a level just below that of the horizontal surfac? of the stainless steel bridqe. It may be found that the Chloroform contacts the underside surface of the stainless steel mesh; this is not critical. Cover the petri dish with the tid and the Jaffe �asher is ready for use. Each time the Jaffe '�►asher is used, the lens tissue and solvent should be discarded artd replaced with new lens tissue and fresh solvent. Appropriate precautions should be taken �Nhen handlinq c�.loroform. b.4.2 Selection of Filter Area for Carbon Coafing - Poiycarbonat•e filters are easily stretched c'urinq handlina, and cuttinq of areas fpr further preparation must be performed with vreat care. The hest method is to use a curved edqe scalpel blade to cut Che filter while it is in 24 Gl.AS$ PE'Ri DISH —, E�ECTRON MICROSCOPE 1 IOOmm • 15mm ) SPEC�MENS � 5T STEEL MESr+ • BR�O �E ! 50 mesn 1 �E TI � 1 � J � 1 : l ��w • .i���,ty� �c� 25 the plastic petri dish. Press the scalpei point on the filter at the beginning of the desired cut, and rock the blade downwards while maintaining pres5ure. It Nill be found that a clean cut is obtained without stressing of the p filter. The process should be repeated alonv ali four directions to remove 3 rectangular portion from the active filtration area of the filter. This filter portion should ;`- be seiected from along a diameter of the filter, and should be about 3 rtvn wide by� a minimum of 15 mm lonq. Areas close to the perimeter of the active filtration area should be . avoided. 6.4.3 Carbon Coating of the yuclepore Fi)t�r The ends of the selec*.ed filter strips should be attacha� to a glass microscope slide using double-sided adhes�ve tape. This must be performed carefully to ensure that the filter strips lie flat on the slide and are not stretched. The filter strips can be ide�tified by using a wax pencil on the glass slide. Af*.er inserting the necked carbon rods into the vacuum evapor�:or, place the glass slide on the sample rotation and tilCing device. The separation between the sampTe and the tips of the carbon rods should be about ` 7.5 Cm to 10 cm. If desired, the am�unt of carbon to be evaporated can be monitored instrumentaily so that a thickness of about 30 nm to 50 nm is deposited on the fitter strips. Alternatively, a porcelain fragment wilt serve as a simple carbon deposition monitor. Place a small drop of silicone diff usion.pump oil on the surface of a clean fragment of white glazed porcelain. Locate the porcelain in the evaporation chamber with the oil droplet towards the carbon rods and at a distance from the carbon rods eaual to that separating the rods from the filter strips. Carbon will not deposit on the oil drop whereas it does on the other areas of the porcelain. With experience, the correct thickness can be monitored visually by observation of the contrast between the darkened areas of the porcelain and the unc�ated areas under the oil drop. Pum$ down the evaporation chamber to a vacuum better than 1�- Torr (0.013 Pa). Use of a liquid nitrogen coid trap above the diffusion pump wi�l minimize the possibility of contamination of the filter surfaces by oil from the pumping system. Continuously rotate a�d tilt the olass siide holding the filter strips, whi�e the carbon is evaporated in intermittent bursts, aliowing the rods to cool between each evaporation. This proc�dure is necessary to avoid overheatina of the filter strips. Overheating tends to cross-link�the polycarbonate which then bzcomes difficult to dissolve in chloroform. 26 6.4.4 �ransfer of the Filter to E'ectron '�icrosccoe Gri�s Remove the glass slide c3rryinq the filrer strios f,�o� ttie evaporator, and using the tecr.nique des�ribed in 5.a.2 cu� four oieces slightly less th�n about 3.�m x 3 mn^ in siz� from each filter strip. The souare of filter should 'it within the circumferen�e of an electr�n micrr,scooe grid. Three cf the filter pieces are to be �rA�,;r�d on 200 mesh copper grids, and un'ess the anslysis is to be for chrysotile only, a fcurth piece shr,uld be �repared on a 2pn mesh gold grid. Tne specimens prepared on coo�er grids are used f�r fiber counting and �ost EDxA er.amir.ations. The preparation on the gold arid �s intended `or EOXA ;�ork on ribers containing sodium. Place a piece ��f t�e carbon-coated fi�ter, carbon s�de �:o, on to the shiny side of an e'ectron .^ir_roscope gri���ng fine tweezers, �.'ck up the orid and �ilter toqether ard place quick:y on to the �hloroform-saturated ;ens tissue in the Jaffe '�lasher, 35 shown in Fiqure 58. It is �mportant that the sampl� be placed on the lens tissue quickly, since hesitatio� whil� the sample is exposed to chloro`orm vapor will cause it to curt. This is a simplified technioue which does not involve drop�inq of chl�roform on to the samples. Some components of the oolycarbon�:te fil;.ers now available dissplve in chloro`orm cnly very slowly. Conseauently, tne grids rr.��ct Se left in the Jaffe '.Jasher for lonoer than 4 days, and the solvent r�ust he revlaced every day. Oepend;ng �n the particular 'ot number of tnE filtzrs, even =his period may be insuff,cient to y»ld sat'sfactor� qrids clear of undissolved �lastic. In this event, or if a more rapid samp'e preoaration is desired, after a ninimum period of 3G minutes in the laffe Washer the lens oaper supporting the grids may be transferred to the condensation washer as illustrated in Figure 5. The condensation washer should ther. be op�rated for ;, period of bet�Neen 30 and 60.minutes, after tivhich the ;rids will have been clearPd of residual pTastic. The rate of condensation in the washer is not critical, �rovided that chlorofi'orm drias rapidly from the cold finger for the �Nhole of the washing period and the condensation level is above the samples. �urinq the d?ssolut�o�, it is recommend?d that tne orids not be al�owed to dry since this has been found to oreativ increase the time re�iuired for compiete dissolution of the polycarbonat2. 27 ,,..._�► —_ _ _.__ _ . _ .- �- - - -- . _ _ . . . �.�...__�__. _ _ . - . . e � CONOENSER SPECIMEN � COl�O wATER SOURCE ADAPTER �COLD FINGER _ , WATER DRAIN FL�:SK r;J SOLVENT t ij � THERMOSTATICAI.�Y CONTRO�LED � . H£ATING MANTLE Figure 6. Condensation Washer. 0 6.5 Examination by Electron Microscopy 6.5.1 Microscope alignment and Magnification Calibration • Atign the electron microsc�pe accordinc to the specifications of the manufacturer. Initially, and at regular intervals, carry out a catib�ation of the two magnifications used for the analysis (aooroximately 20,OG0 and 2,000) u5ing a diffraction gratino replica. The calibration should always be reoeated after any instrume�tal maintenance or change of operating conditions. The maqnification of the screen image is not the same as that obtained on photographit plates or film. T�e ratio between these is usually a constant value for the instrument. It is most important that hefore thP maanification Caiibra!ion is carried out the sa�ole he�aht is adjusted so that the sample is in the eucentric position. �•28 ,^.. _,..w � ----- -�_�.. _ _ . . u.5.2 Calibration of EDX,� System The purpose of the calibration is to enable quantitat:ve composition data, at an accuracy of about 10`= of the elemental Concentration, to be obtained from EOxA spe�tra of silicate minerals involving the elements sodium, _ mdgnesium, aluminum, silicon, potassium, calcium, mancar.ese � and iron. If quar�citative det�rminations ar� reGuired �or minerals containing other elements, suitable caliCration information may be incorporated in the computer analysis. The well-characterized standarc�s recommended �ermit calibration of any TEM-EOXA combination which meets the J instrumental svecifications of Sectian 4.2, so that data f rom different instruments can be compared. The standar��s used for calibration, and tne elements which thpy represent, are shown in Table 2. TABLE 2. SILICATE �'1INERAL STANOARDS Elements Mineral Standard Na, Fe, Si Riebeckite Mg, Si Chrysotile Al, Si 4a�loysite K, Si Phlogo�ite Ca, Si '�1o11astonite M�, Si Bustamite The compositions of these standards have been determ�ned by microprobe analysis, and the TE��t grids were prepar?d from fragments ef the same selected mineral specim�ns. They permit the corrputer �roqram of Appendix A to 5e used with any TEM-EDXA system. Place the first grid into the microscope, forn an imaoe at the calibrated hiqher magnification of ahout 20,000, ard adjust the specimen height to the eucentric poir.t. Tilt the specimen towards the X-ray detector as reouired by �he instrument geometry. Select an isolated fiber or particl� les5 than 0.5 u m in width, and dccumulate an E�XA soectrum using an electron orobe of suitable diameter. �hen a wel? defined spectr�;m hac been obtained� oerfor�n an aoprooria:e background subtraction and obtain the net oeak araas for each element listed. using ener�y windows centered on the 29 - -- -.. 4 r peaks and about 130 eV wide. Compute th? ra�io of the p?ak area for each specified element relative to the peak area for silicon. Repeat the procedure for about 20 particles of each mineral standard. Analyses of any obvious foreign particles should be rejected, and the data from any one stardard should be reasonably s21f-consistent. Calculate thp arithmetic mean peak area ratios for �ach specified element of each mineral standard. fhese values are rsquired initially as input for the fiber identification program, and apart from occasional routine checks to ensure that there has been no degradation of the detector resolution, the calibration need not be repeated ��nless there has been a change of instrumental operating conditions. 6.5.3 �rid Preparation Acceptability Inse►t the specimen qrid into the electron microscope and adjust the magnification to a value sufficiently low (300 - 1000) so �tiat complete qrid openings can be inspected. Examine at ieast 10 grid openings to evaluate the fiber and total particula*e loadings, the uniformity of the particulate depos�t, and the extent to which the carbon film is unbroken. The grid must be rejected from further analysis if: a) the grid is too heavily loaded with fibers to perf orm an accurate count. Accura�e counts cannot be performed if the grid has mo^e than about 50 fibers per grid opening. A new grid pr�paration must be made using either a smaller volume of w�ter or a suitable volume of the water diluted with fiber-free water; b) the overall distribution o noticeably non-uniform. A be made, paying particular particulate dispersal and f tFe deaosited d�bris is new qrid preparation mu5t attention to proper filtration procedures; c) the arid is too heavily loaded with debris to allow examination of individual particles by SAED and EDXA. A new grid preparation must be made using either a smaller volume af water or a dilution of the original water sample; d) a larqe proportion of the grid ope�ings have br�ken carbon film. Since the breakaqe is usualiy more frequent in areas of heavy deposit, counting of Lhe intact openings could lead to biased results. Therefore, a new grid preparation must be made from a more cor;,pletely dispersed sample, a reduced volume of sample, or alternativety, a thicker carbon film �ay be necessary to support the larger particles. 30 6.5.4 Procedure for Fiber Countinq The number of fibers to be counted depends on the statistical precision de5ired. In the absence of fibers, ^ the area of the electron microscooe qrids which must be examined depends on the analyticai sensitivity required. For statisticat reasons, d;scussed in Section 7.2, the fibers on a minimum of 4 grid openings must be counted. The precision of the fiber ccunt depends no� oniy on the � total mimber of fibers counted, but al:� nn their uniformit.y from one grid ope�ing to 'the next. In practice, it has been found that terminat°on of the fi5er count at a minimum of 100 fibers or 20 grid openings, ��hichever occurs first, yields results �Nhich usually require no further refinement. Additional fiber countiny will be necessary if greater G�ecision is required. At least three grids prepared from the filter must be used in the fiber count. �everal grid ooenings are to be selected from each grid, and the data are a11 incorporated in the catculation of the results. This permits the measurements to be spread across a diameter of �he oriqinal filter, so that any qross deviations from a uniform deposi�ion of fibers should be detected. Figures 7 and 8 show specimen fiber counting raw data sheets which represent the minimum standard of data reportinq for this analytical procedure. Figure 7 shews page 1 of the raw da�a t�bulation, ��hich contains all specimen preoaration details. Figure 8 is a continuation sheet for the fiber classification ar,d �easurement data; several of these sheets may be required for ana�ysis of a sample. Select a typical grid opening from one of the grids. Set the magnification to the calibrated higher value (about 20,000). Adjust the sample height until the featur�s in the center of the screen are at the eucentric point. Check that the goniometer tilt is set at zero. Reduce the maanification to the lower calibrated value of about 2,000. heasure both dimensions of the grid opening imag� in millimeters, u5ing the markings on the fluorescent screen. In columns l and 2 specify the sequential number of the grid opening, and its dimensions. These t�No coTumns are not used again unt��l fiber counting is co�rtnenced in the next grid opening to be examinea. Adjust the magnificati�n to the upper calibrated �iatue, close to 20,000, �nd position the grid ooening so that one corner is visib�e on the screen. Move the imaqe by adjustment of only �ne translation control, careful'�• oxamining 'he sample for fibers, ��ntil the opposite side of the opening is encountered. Move the image by one screen ��idth �sing the 31 � �, ASBE570S ANA�YSIS - aATER SAMPLE DATA 'cu' --{ SAMPLE: J08: I ', PREP: By _ Oate - - �OUNT: By Oate - - P40CESS: By [NSTRUMEYT: MAGtvIFICATI0N5: Grid Count OIL'JTIONS: 0 ' I 1 Volume Taken (ml) Final Volume ;ml; _ 2 Volume 7aken (mL) �inal Volume (mL) fINAI PREPARATtON FIL'RATiON: Vol. Piltered (mL) • COCE ' 1 i � � Date - - I Ac:ive Area {cm�) � i „— -- � COMMENTS: (for inClusion in computer print-out; Tormat in 5 lines of 50 characters) � I � ; FIBER CLASSIFICATIQNS: ! COIiNT. NAM �M CM C� CQ C�!Q CC�O Jf AD �X �DX AQ A00 �ZO a.Z? i PROCESS• ' � fI6ER TYPE � CLASS;FI�.1'ION ; Ft?Et2 'yP` � CLMS�:=tCr�iGr� � NOTES: Pr�paration: � Examination: i I I Figure 7. Sheet for R�cording Water Sample Oata. �? a ..-_ _:r: :_ �:. ' -`I N I i ' � ' � i � ' � . . y . ;` � i ( � ; � I � I I I 1 � � I I ' I ' ' � ( i i I f � � � � I 1 . 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' � N ` I I � �� 25 1 ' 1 ! i � , ' — ' '_� c� i `� � ; ; � � � i ( I � I � � : �� � o �� � i i � � � I � i ' L I . • t �� � ; I � � o ! �� � � � i � r � � � � � i —_J cl '' � �� i E � � � � ' I I ' i� ' ' a i ' � � � . i � v ; . � . � i � � � ' j � � � � i � a.� � � � � i , i ' I y { �� � � ��, � I � � � i(;� , i i y , � �� ���� � I' i � �� i I � i �� i N � i i I ! " � c � � I � ; ''� I � I � � ( � � � � ; � �� � { I • � • X 7{ , I :.i y � �j r,� x� R x X X X x f � d� o i]t =1 I � i i i I xi '��'� XI x� X xI xl xl XI Y� x.c� x' x� p� : d� :� ovi � I I � i I ( I I � � � � ' , ' w . s , i � • �� = i �'' � � 1' � I I 1��( I I I i . 33 -----'-r'" -�.._ __ . y. other translation control, and then scan the ir.,aqe in the reverse direction. Continue in fihis manner until the entire grid opening has been inspected. �lhen a fiber is <> detected, classify i� according to the procedures descrihed in Section 6.7, and then insert the approoriaLe classification on the data sheet. "�easure the lenath and width of the fiber imaqe in millimeters and record th?se i�. � the appropriate columns of the data sheet. Do not record fibers of obvious biological origin or diatom fragments. Continue the examination until I00 fibers have been recorded in all classification categories of interest, or until 20 grid openinos have been inspected. The data should be drawn approximately equally from the three grids. In all samples, fibers on a�ninimum of 4 grid openings must be counted. Fibers less than 0.5 um in . length will not be incorporated in the fiber concentration calculation. 6.5.5 Estimation of Mass Concentration If the primary objective of the analysis is to determine the mass concentration, the fiber countinq should be approached in a different manner. The number of fibers which must be counted in order to achieve a reliable estimate of the mass concen}ration depends primarily upon the range of the fiber diametzr distribution. The mass concentration measurement is most sensitive to fibers of " � iarge diameter, which unfortunately are among those which occur infrequently. When [he diameter distribution is narrow, such as that found in the tase of chrysotile fibrils, then the mass concentration has ap�roximately the same precision as that of the number concentration. , However, the mass concentration may be actually meaningless when calculated from a low number of fibers observed during a routine fiber count, if these fibers have a broad . distribution of widths. If the mass concentration is the pri,nary interest, and the precision required is greater than is possib'e from the normal fiber count, a dif`erent approach to the fiber coun� must be used. Initially, establish the larvest �idth of fiber which can be detected on the grid by a cursory survey, at a reduced magnif�cation, of a laroe number of grid openings (about 50). Calculate the volume of this fiber. Adjust the magnification to a value such that a width of 1 mm on the screen corresponds to 10� of the width of the previously selected larqe fiber. Carry out � routine fiber Count for a minimum of 100�fibers, recordina onty fiber images greater than 1 mm in width. Continue Countinq until the total volume of fibers is at least 10 times the volume of the originally selected large `iber. The precision and accuracy of this technique has not been 34 M investiqated fully, but for samples �Nith broad width distributions it is capable of yieldino ;ignificantly more precise mass determinations than are obtainab)e by the conventional fiber count. 7he remaining problem concerns the assumption that the � widths also represent the thicknesses cf the fihers. Heasurements of particle thicknesses can be made separately, using the shadow castina technivue. Before the filter is carbon coated, apply a vacuum coating of platinum-carbon or gold to the active surface of the ~ Nuclepore filter at an anqle of 45°, In the TEM, the fibers will then display shadows on the carbon film which approximate to their thicknesses. Suitable techniques for shadowing are described in the o��er by D.E. Bradley inctuded ,n the Selected Bibliogr,:phy. 6.6 Fiber Counting Criteria 6.6.1 Fiber Counting Method Fiber counting with this analytical �nethod will be performed only by the qrid openinq technique. If a specimen grid is too heavily loaded for examination of entire grid openings, a more reliable result is obtained hy preparation of a new filter, usinq a smaller volume of sample. 6.6.2 Fibers blhich Touch Grid Bars A fiber which intersects a grid bar will be counted only for two sides of the grid openinq, as illustrated in Figure 9. The length of the fiber will be rec�rded as twice the visible lenqth. Fibers in�ersecting either of the other two sides wilt not be included in the count. � 00 NOT COUNf r� � � � � ' � CouNr as � i .... . � I � �:,, . �. , �1:..!� ; .� ti , JO NOT b,•;.,.�..,. / 1:` CCUNt COUHi 4S/ �� � / —: `w--� _: � Figure 9. Count1ng of Fibers Which Overlap Grid 3ars. 35 w This procedure ens��res that the numerical count will be accurate, and that the best average estimate of length has � been made. 6.6.3 Fibers Which Extend Outside the field of View Ouring scanning of a grid openinq, fibers which extend � outside of the field of view must be counted systematically to avoid double—countinq. In qeneral, a rule must be established so that fibers extending outsi�e the field of view in onTy two quadrants are counted. Fibers without terminations in the field of view must not be counted. The procedure is illustrated by fiqure 10. The lenqth of each fiber counted is established by moving thP sample, and then returnirtg to the original field of view before scanning is continued. � Figure 14. Counting of �ibers Which Extend Outside the Fi•eld of View. , 6.6.4 Fibers with Stepped Sides " A fiber with stepped sides will he assianed a�Nidth mid-way betr�een the minimum and maximum widths. 36 eucentric oosirion. Tift the fiber until a pattern apoears which is a symmetrical, two dimensional array of soots. The recognition of zor,e axis alignment c�nditions reGuires some experience on the part of the overator. During tiltir.g of the fiber to obtain Zone axis conditions, the m�nner �n which the intensities of the spots vary sheuld be observed. If �Nea� reflections occur at so�e points on a matrix of strong reflections, t_he Dossibility of multiple diffraction exists, ar,d some caution should be exercised in selection of diffraction spots for r��easurement. A full discussion �f electron diffraction and multipie diffraction can be found in the references by J.A. Gard, P.�. Hirsch et al, and H.R. Wenk, included in the Selected Bibliography. Not all zone axis patterns which can be obtained ar� useful or definitive. Only those which have �losely—spaced reflactions correspondino to low indices in at least one direction should be recorded. Patterns in Nhich all d—spacings are less than about 0.3 nm �re not useful and are usually very wasteful in computer time. A useful guideline is that the lowest angle reflections should be ��ithin the radius of the first gold diffraction ring (111), and that patterns with smalier distances between reflections are usually the most definitive. Five sp�ts, closest to the center spot, along two intersecting lines of the zone axis pattern must be SeleCted for measurement, as �llustrated in Fig�re 14. • SPOTI SPOT 3 �POT 2 • e2 e� � SPOT 4 e3 • � ea • � SPOT 5 • Figure I4, Measurement of Zone Axis SAED Patterns. - 41 � � � The distances of these spots from the center s�ot and �hP tour angles shor+n are the input for the comvuter proqram. Since the center spot is usually vzry over-exposed, it dees not form a suitable or;gin fcr measurerrent. The reauired distances must therefore be obtained by measuring between pairs of spots symmetrically disposed about the center spot, preferably separated by several repeat distances. The distances must be measured with a precision of better tt,an 0.3 mm� and the angles be'ter than 2.5°. The diameter of the first or Second ring of the calibration pattern (111 and 200j must also be measured with the 5ame precision. _ The camera Constant (aL) required for the computer program is 7iven by: where: al = aD h2+ k2 + }2 a� Wavelength of �;�e inci�ent electrons L= Effective camera lengtn in rtm 0 a= Unit cell dimension in Hrgstroms 0� Diameter of the (h, k, 1) diffraction ring5 in millimeters h, k, 1= Miller indices of tne sca:terina olane of the crystal. Using gold, the camera constant is qiven by: �� � 2.3548 D (`irst rinq) aL � 2.0393 D (second ring) Analysis of a fiber by EOXA is required in this analytical procedure. Interpretation of the EDX� spectrum may be eithPr qualitative or quantitative. For qualitative interpretation of a spectrum, the elements oriqinatinu from the fiber are recorded. For quantitative interpretation, the net peak areas, after backqround subtraction, are obtained f�r the elements originatino frcm the fiber, As discussed in Section 6.5.2, this method provides f�r quantitative interpretation for tt;ose minerals which contain silicon. , 42 To obtain an E�XA sp?ctrum move the imaqe uf thA Fiber to the center of the screen and remove the objective aoer�ur•�. Select an appropriate electron beam dia�eter and defler_t the spot to impin9e on the fiber. DeoPnding on the instrumentation, it may be necessary to tilt the samole arc in some instruments to use Scanning Transmisci�n _l�c�ron Microscopy (STEM) moda of operation, The ti�e for acouisition of a suikabte spectrum varies ��ith the fiber diamet��, and a15o with instr��mental factors, For quantitative interpretation, spectra should have a statistically valid number of counts in each peak. A.nalyses of small diameter fibers which contain sodium ar? the most criticai, sinc�� it is in the lew eneroy range that the X—ray detector is �east sensitive. �ctor�ingly, it is necessary to acquire a spectrum for a sufficiently long period that the presence of sodium can be detected in such fibers. It has been found that satisfactory quantitative analyses ca� be obtained if acquisition is ��nti�ued until the background-subtracted silicon K� peak integral exceeds 10000 counts. The spectrum should then be manipulat2d to subtract the background and t� obtain the net areas of the elemental peaks. After quantitative EOXA classification of some fi5ers by computer analysis of the net oeak areas, it�may be possible to classify further fibers in the same sample on the basis of compar�son of spectra at the instrument. Freouently, visual com�arisons can be made after so�e�hat shorter aCquisition times. 6.7.3 Anal�sis of r"iber ldentification Cata Since the fiber identification procedure can 5e involved and time—consuming, a Fortren computer program has been provided, the listing of which is given in Appendix A. This program permits the EDXA and zone axis SAE� measurements to be �ampared avainst a library of compositional and structural data for 226 minerals. The mineral library includes fibrous species which have been listed by several authors, toaether with other �inerals which are known to be similar to amphibole in either their compositions or somE aspects of their crystalloqrapny, AddiLional minerals may be added to the library if the� ar� thouqht to be of concern in particular s�tuations. Rejection of a mineral by the program indicates thaL ei�her the compositional or crystallo�raphic data for the �ineral in the library are inconsistent with the mP_a5urem�r,�5 Tade on the unknown fiber. Oemonstration that the �easureTer�s are consistent with the data for a particular test �irera' daes not uniauely identify the unknown, since thP possibility exists that data from oth?r minerals �ay �lso 43 � be consistent. It is, however, very unlikely that a mineral vf another structural class could yield.data consistent with that from an amphibole fiber identified uniquely by quanti- tative EDXA and two zone axis SAED patterns. :°'. The computer program classifie5 fibers initially on the � basis of chemical composition. Either Qualitative or auantitative EOXA information may be entered. The ` procedure using qualitative EDXA consists of entering the � list of elements which originate from the particle. F�r quantitative EGXA (silicon-containing minerals only), the list of elements and the areas under the corresponding X-ray emission peaks, after hackground correction, form the inpu+ data for the computer program. The width of the fiber is also required as input into the proqram. The program will select from the file a list of minerals which are consistent in composition with that measured for t'�e < unknown fiber. To proceed further, it is necessary to -'obtain the first zone axis SAED pattern, according to the `instructions in Section 6.7.2. It would be attractive to specify a partic�lar zo:ie axis pattern to be obtained for confirmation of amphibole, particularly if such a pattern could be considered characteristic. Unfortunstely, for a fiber with random orientation on the qrid, no specimen holder and aoniometer currently available �ill permit convenient and rapid location of two pre-selected zone axes. �The most practic3l approach has been adopted, which is to accept those low � index patterns whiCh are easily obtained, and then to test their consistency with the structures of the minerals already pre-selected on the basis of the EDXA data. Even the structures of non-amphihale minerals in this pre- selected list must be tested against the zone axis data obtained for the unknown fiber, since non-amphibole minerals may yield similar patterns consistent with amphibole structures in some orientations. The zone dxis SAEO inter�retation part of the proqram wili cons'de►' all mine�als previously selected from the file as being chemically compatible witi� the EDXA data. It will then return a second and usually reduced �ist of minerals for which solutions have been found. A second set of zone axis data from another pattern obtained on the s�me fiber can then be processed either as further confirmation or ;,o attempt elimination of an ar^biguity. In�.addition, the anqle measured between the orientations of the two Zone axes car be entered into the corrputer to be checked for consistency with the structures of minera;s. Caution should be exercise� in rationalizing the inter-zone axis anqle, since if the fiber Contains c-axis twinnin the two zone axis SAED patterns may originate from theyseparate twin crystals. 44 In pr�ctice, thp full proqram will normall�� 5e aoplio� �� very few fibers, unless precise identification of �11 fibers is reouired. 6.7.4 Fiber Classification Categories It is not always possibl2 to proceed to a definitive identification of a fiber; this may be due to instrumental limitations or to the actual nacure of the fiber. In many analyses a definitive identification of each fiber may not actually be necessary if there is other knowledqe available about the sample, or if the concentration is belo�x a level of interest. The analytical procedure must ther?fore take account of both instrumental limitations and varied analytical require�ents. Accordinqly, a system of fiber classification has been devised to �ermit accurate recording of data. The classifications are shown in Tahles 3 and 4, and are dir�cted tewards identification of chrysotile and amphibole respectively. Fiber; wiil be reported in these categories. 7he general principle to be followed in this analytical procedure is first to define the most soecific fiber classification (target classification) which is to he attempted. Then, for each fiber examined, the classifica- tion �Nhich is actuatl� achi2ved is recorded. �epending on the intended use of the results, criteria for acce�tance of fi�bers as "identiried" can then be established at any time after completion o` the anaiysis. In an unknown sample, chrysotile will be reQarded as confirmed only if a recorde�, calibrated SAEO pattern from one fiber in the CD category is ohtained. Amphibole .rill be regarded as confirrred only by obtaining recoroed data which yields exclusively amphibole solutions for fibers classified in the AZQ, aZZ or AllQ categeries, 6.7.5 Procedure for Classification of Fibers �ith Tuhular Morphology, Suspected to be Chrysotile hlany fi5ers are encountered which have tubular morpholoa�� similar to that of chrysotile, but which de�y further attempts at cha�acterization by either SAEO or EGX;�. They may be nor�-crystallire, in which case :i�ED techniaues ar� not usefui, or the� may be in a position on the ari�' ;�h��h does not permit an EDXA soectrum t� be obtained. Alternatively, the fiber may be of organic oriQin, but not sufficiently definitive that it can be disre�arded. Classification attempts will meet with varicus degrees c� sucCess. Figure 15 shows the C13s5ifica�ion nroced�,re to be used for fibers which display any tUbular ,�crpnoloa�i. 45 TM CM CD CQ CMQ COQ NAM TABLE 3. CLASSIFICATION OF FIBcRS '�ITH TUBUTAR MORPHOLOGY - Tubular Morphology not sufficiently characteristic •for classification as chrysotile - Characteristic Chrysotile Morphology - Chrysotile SAED pcttern - Chrysotile composition by Quantitative EDXA - Chrysotile Morphology and composition by Quantitative EDXA - Chrysotile SAED pattern and composition by Quantitative E�XA - Non-Asbestos Mineral TABLE 4. CLASSIFICATION OF FISERS WITHOUT TUBULAR �iORPHOLOGY UF - Unidentified Fiber AD - Amphibole by random orientation S�ED (shows layer pattern of 0.53 nn spacing} � AX - Amphibole by q�alitative ED��1. Spectrum �as ele�ental - components consistent with amphibole ADX - Amph:bole by random orientation SAcD and Qualitative EDX� AQ - Pmphibole by Qvantitatire E�XA A2 - Amphibole by one Zone Axis SAED AOQ - Amphibole by random orientation SAEO and Quantitative EDXA AZQ - Amphibole by one Zone Axis SAED pattern and Quantitative EDXA All - �Amphibole by two Zone �xis SAED patterns with consistent inter-axial angle AllQ - Pmphibole by two Zone Axis SAED patterns, consistent inter-axial anqle and Quantitative EDYA VAM - Non-Asbestos Mineral 46 FIBEFi WITH TUBULAR MORPHO�OGY IS tiber morphology :naraCtzrtstic of [hat displjyed b•� r=rere�ce C��/SOL�12? �xaMine by SAEO Fat:ern nut I Ch r+sotile :��ySOtile Dattern �at:ern nu: 7r?Sen! or ind:Stir.CC TM � Examine Dy audntitattv2 :�X:. �Om00'lt'Gn n0[ i,hr�50Li12 Chdt o` Chrysotile CCmDO51C1C� t�a Scec�rum NCM TM CO � � i �,camine �v SAED �hrySOC'�^ �3C�@�'1 ^OC �at_ern c�rysct�te °�CCe�n noc :r=sent or indi5t�nc� CM �,cam+ne �Y quanti:a�i•�e ;�fA ���j�50t1i2 :OR�DOS1!'011 f10: coTposit�on � Chat �f Cnriso;ile VO $DeC_r;�m ] cM � E,camine oy quantira;i•�e E�xA ::omoos�:•cn �ot C��at of �hrysot�le 'lo Soec:rum ' CD :��ySOCt'.B �:m0051:'�n Figure 15. Classification Chart for Fiber '�lith Tubular l�lorphology. � � 0 47 � The chart is selr explanatory, an� essentially every fiCer is either rejected as a non-asbestos mineral (PaA.M), or classified in some way which could still contribute to the chrysotile fiber count. Morphology is the first consideration, and if this is not similar to that usually seen in chrysotile standard samples, the initial classification is TM. Regardless of the doubtf��l morphology, the fiber ��ill still be examined by SAED and EDXA methods according to Figure 15. Where the morphotogy is m�re def�;�itive, it may be possible to classify the fiber as having chrysotile morphology (CM;. The morpho��gical characteristics required will be: a) the individual fibri:s shoul� have high aspect ratios exceeding 10:1 and be about 40 nm in diameter; b) the electron scattering power of the fiber at 60 to 100 kV acceleratinq potential should be sufficiently low for internal structure to be visible; and ' c) there should be some evidence of internal structure sugqesting a tubular appearance similar to that shown in Figure 16A, which may degrade in the electron beam to the appearance shown in Figure 166. Every fiber having these morphological characteristics will be exa�ined by the SAED technique, and only those which give diffraCtion patterns with the precise characteristics of Figure 17 wiil be classified as chrysotile by SAED (C�}, The relevant features in this pattern for identificati�n of chrysotile are indicated. The (002) reflections should be �examined to determine that they correspond approximately to a spacing of 0.73 nm, and the layer line repeat distance should correspond to 0.53 nm. There should also be "streaking" of the (110} and (I30) reflections. Using the millimeter calibrations on the microscope viewing screen,. these observations can readily be Tade at the instrument. A TEM micrograph of at least one representative fiber will be recorded, and its SAED pattern wi11 also be recorded on a separate film or plate. This ptate xill also carry cali- bration rings from a knowrl polvcrystalline substance such as gold. This calibrated oattern i� the _o�nl� documentary proof that the particular fiber is chrysotiTe- and not some other tubular or scrolled saecies such as ha�loysite, paly- gorskite, talc or vermiculite. The proportion of fibers which can be success`ully identified as chrySotiTe by SAED is variable, and to sone extent depend2nc on both the instru�ent and the precedures of �he operator. The fiber� that fail tr, yield an ider.tifiable SAE� pattern .will remain in the TM or Gh categories unless they are examined by cDXH. 48 ,,._,.:__. Figure 16A. TEM Micrograph of Chrysotile Fib�il, showing htorphology. .� ; • . ;. ' . , ,, Figure 166. TEM t-�icrograph of UICC Canadian Chrysotile Fiber after Thermal Degradation by Electron Beam Irradiation. 49 � � r � __ � � , .DS7nm / - � tiQ, � t30 � i Figure 17. SAED Pattern of Chrysotile Fiber with Diagnoscic Features Labelled. Necessary criteria are the presence of 0.73 nm spacing fpr the 002 reflections, 0.53 nm spacing for the laver line repeat and characteristic streaking of the 110 and 130 reflections. 6.7.6 In the �oza anaiysis of cnrysotii� there are only two elements which are relevant. For fiber classification, the EDXA analysis must be auantitative. If the soectrum displays prominent peaks from magnesium and silicon, with their arpas in the ap�ropriate rdtio, and with only minor peaks from other elements, the fiber wiTl be classified as chrysotite by ouantitative EDXA, in the cateqories CQ, CMQ or COQ, as appropriate. For chrysotile analyses there are essentially three possible levels of analysis: 1. morphoioqical and SAEO discrimination only (Tarqet classification CD); 2. in addition, EDXA of only those fibers unclassified by SAEO (Tarqet classification CO); 3. EOXA in addition to SAED on all fibers (Target classification COQ). Procedure for Classifitation of Fibers Without Tubular horphology, Suspected to be A.mphibole Every particle without tubular morphology and which is not obviously of biological origin, with an asoect ratio c� 3 to 1 or greater and having parallel or stepped sides, wi11 be considered as a suspected amph��bole f;ber. Furthzr examination of the fiber by SAE� and E�XA techniaues wil� 50 meet with a variable daqree of success, de�endinq on th� nature of the fiber and on a number of instrument�l limitations. It wi11 not be posSitilQ to identify every fiber completely, even if time and cost were of no concern. t4oreover, confirmation of the presence of amphibole can he achieved only by quantitative interpretation of zene axis SAEO pattern5, a very time-consuming procedure, Accordingly, for routine samples fron unknown sources, this analytical procedure limits the reeuirement for zone axis SAED work to a minimu� of one fiber represent�tive of each compoSitional cldss reported. in some samptes, it may be necessary to identify more fibers by the zone axis technique. When analy2ing samoles from ��ell-character�zed sources, the cost of identification by zone axis mP*nods may not be justified, The 0.53 nm layer spacinq of the ran�om orientation SAc"D pattern is not by itself diagnostic for amphibo�e. However, the presenCe of c-axis twinning in many fibers leads to contributions to the tayers in the patterns by several individual parallel crystals of different axial orientations. This apoarently random positioning of the spots along the layer tines, if also associated �ith a high fiber aspect ratio, is a characteristic of amphibole asbestos, and thus has some limited diaanostic value. If a pattern of this type is not obtained, the identity of the fiber is stili amb�4uous, since the absence of a recognizable pattern may be a consequence of an unsuitabl? �rientation relative to the electron bea�, or the fiber may be some other mineral species. Figure 18 shows the fiber ciassification chart for suspected amphibole fibers. This Chart ShOwS all the classification paths possible in analysis of a suspected amphibole fiber, when examined systematicaliy by SAED and EOXA. Initially two routes are oossible, deoending on whether an attempt to obtain an EDXA soectrum or a rardom orientation SAED pattern is made first. The normal procedure for analysis of a sample of ur,known oriqin will be to exam;ne the fiber by random orientation SaED� qualitative EDXR, quant;�ative cCXA, and zone dxis =.=.`0, in this sequence. The final fiber classification assiQnea wi;l be defined either by successful analysis a� the target level er by the instrumenta' limi���ionS, Th� maximum classif;cat�on achieved for each fiber will be recorded en tne �ounting sheet in the approoriate Column. T;e var�o�s ciassification cateqories can then he comhin�d �n any desired k�ay for calculation of the f?5er cencentration, and a complete record or" the results frcm each fiber is msintained for r��ssessment of the data if necessary. clJ f � /i7CP wITHOUT "UBVI�� yC9ov7���Y z..... . p�. '�e�. ::�i x.;... :��•'•r -. ..rnu� ' ...H, .1.'en<i � �.• , . . ;�[; - . . ��0'.KI� an I .. �y . � � .�.. ..�. . . . .iC..�. l,il ^' ..�t�. I�Y�V ' • � 'b :>e!:rv� a�':<.. .r• . .! . � � ��. �_�...<'• '.Y. ...... I�Y 1 . � l�� _�_., � . � ��f. YJYI 3� .. Jql Jw1+I�t�.� :)�1 I . � �Hr }ppf. an � �'l` � ' ��on�xl�' I . Jp.� :•� :�;:•u t .�e� :)�: . . •'r�e+: ,� � ����t .�. i .. .� � . �S � i ✓o••eo i�e _e 1 I Ndu ! • �� .. ( .i . .i .. � � r� ' 'aii :G�� �_�M: _ r0Q ` � ; � y - C :•I � '�(:' f . . ,::� . �l :,,:•_ V . . - �-,l ;_� , . w , , ..: , . , ..:. .. .. ..... ...,. :�.:... :., .. .: = :.. , ,.� � .� ... �____ � �p :.�:..� � � � � � _, ^ ' 'e^.'E: �v . � . , �". . . .. ' � i -- .�. aoi:� ;—`_' . a2 i � � IR1` .. ' `1GN1 ' � � i i l. V�ry' .. ..a . .. � ,�. .�.. i ' � ..�a I (y�y� �v�� :G] ' �. T i i ,�. '' i ,a � _c �,,,, , :Z� � �` � T :�, � - � �: . :. -:� . � ,:�:::,.�- .. .. . �, .Q .� _� ; ;�= '`� .. .. .� -�,�`_ . r-.---�--� `=� 1. j ,... ., : m -�^ i .��� ' �Z. , �o s�.n � �� _ '� �� ,b :... . ��. . : ,� -,�1,- °Cp' � ,•z; : �:.... �z� �:� _ . . +�c+ x'< *c �'>° .i•d .t r• . . ?[: �0' �` :•a : � t:;: � -:e.:,..;� �. . . , � . ~_L � .:� V�YI JZ� �i. � .t' 1+ . . 4� � Figure 18. Classification Cnart for F�ber 'rlithout Tubular ��tor�holooy. Bold Lines indicate the Preferred Paths. 52 Dependinq on the particular situat�on, rour leve?5 n� analysis can be defined in r_his analyticat �rocedure, and these are shown in Table 5. In the routine unknown sam�le, a levet 3 analysis �ill be required if the presence of amphibo'e is to be confir�ed. For this level of analysis, attemGts �il? be made to raise the classification of ev�ry fiber to the PGq category. tn addition, at least one fiber from each type of suspectpd amphibole found will be examined by zone axis S�ED �ethods to confirm the identification, TABLE 5. LEVELS OF ANA�YSIS FOR AMPHi30LE Level of �pp�ication Target Required Classification Analysis Classification for Confirm�tion of for all Fibers Amphibole in e Proportion of th2 �ibers 1 2 3 4 Routine monitoring of known and well-charact- erized sources for one mineral fiber type. Routine monitoring of known and well-charact- erized sources where discrimination Letween two or more amphiboie fiber types is required. Routine samples from uncharacterized sources in which pr.esence or absence of amphibole is to be confirmed. Samples where precise identification of all amphibole fibers i; an impor*.ant issue. ADx ADQ aoQ azQ 53 Not Applicable P�ot Appl'cable All, AZQ or AllQ - Sol�!tions must inc;ude only amphiboles. AZLQ - Solutions must incluc� on�y am�hibol?5. w � � . 6.6 Blank and Control Determinations To ensure that contamination by ex�raneous fibers durinq sa�o'e preparat�on is insignificant �ompared with the results reported on � Samples, it is necessary t� establish a continuous proGram of blank measurPments. Initially, and at intervals durinq an analytica' program, it is also necessary to ensure that samples of known fiber concentrations ca� be ar��lyzed satisfactorily. 6.8.1 Blank Determinations At least one blank determination will be made along wi�h every group of samples prepared at any one time. For the blank determination, a 0.1 �m �uclepore filter will 5e prepared by filtration of 100 mL of oze�e-UV tr�ated fiber-free water if using ZS rrm diameter equipment, and 500 mL treated water if using 47 mm diameter equipment. If the samples have been preserved with mercuric chloride, an equivalent amount of the solution should be added to the water used for the preparation of the blank. This blank filter will be carbon coated at the same time as the group of samples, and solvent extracted in the same Jaffe '�asher. All aspects of the samqle preparation will then be i,aentir.al to those for the actual samples. Ail fibers on 20 grid openings of the b�ank sample ��ill be recorded. Yhe mean fiber concentration for the blank must te less than 0.05 MFL or less than lo of the loweSt individual value reported in the sampies concerned, whichever is the arPater value. If a value higher than these criteria is encountered, satisfar_tory blank values must be denonstra=ed before further analyses are carried out. If it is susoectec �:�at ssmp'es could have been contaminated during the original preparation, the duplicate bottles should be used for the repreparation of the samples concerned. 6.8.2 Control Samples Control samples must be incorporated into sample anaiysis ` programs in order to demonstrate that the expected results can be produced from sampies of known fiber concentration. ; Such reference suspensions can be prepared using a�poules ; of stable fiber dispersions listed in Section 4.3.10. It is recommended that the range of fiber concentrations found in the real samples should be simulated using the rAference suspensions. The sealed am�oules of fiber dispersions become unstable when they ar? opened, and the fiber concentration value should not be rel'ed upon for more than 8 hours after opening. Accordingly, it is recommended that, upon opening a dispersion concentrate ampo�le, severat reference susoensions of �ifferent fiber ` concentrations be prepared in sample bottles. These 54 botties can tf�en be stored for �reoar,jtior. and anal�.sis along with water sampies of urknown fiber Conrontrations. 7. C�LCUI:aTION OF RESULTS The result� are conveniently calculated usino � �qmDu�er �ragram, the � listin� of which is provided in Appendix B. �The r�e:hods by wh;ch the calculations are made are described below. 7.1 Test for Uniformity of Fiber Deposit on Elect�on Hicroscooe Urids � A check must be made using the chi-square test, to determine whether the fibers found on individual grid ooenings are randomly and uniformly distributed among the qrid openings. If the tota' number or fibers fcund in k grid openinas is n, and the 3r2�S or the k individual grid openinqs are designated A1 to AK, ttien the total area examined is i = k A = � Qi i = 1 The fraction of the total area exar�ined which is re�:-esented by the individual grid opening area, ��� is qiJen by A�/F, If the fibers are randomly dnd uniformly diseersed over the k qr�d openings counted, the expected number of fibers fal�inq in one ar�d opening with area AT is rN�. If the observed n;,mb��r fcund on � that grid opening �s n�, then: i = k 2 _ � (�i - np��2 '� n p i=1 � This value is comp�red with significance p01r,tS of the ;t2 distribution, having (k - 1} deqrees or freedom. Sianificance levelc lower than O.lo are cause for tne sampt� analysi�s to be rejected, since this corresoonds to a very tnhOm002n?Ou5 de�os�t. If this occurs, a new filter should �e preparQd, oaving r*ore attention to both uniform dispersal of the sus�ension ard the ry fittration procedure �s descri�ed in Secti�n 6.3.2. 55 � 1.2 Calculation of the �ean and ConfiCence Int�rval of the Fiber Concentration In the fiber count, a maximum of 20 grid openings have b��n �.9�Gi?C from a population of grid openinqs, and it is r?Qu�red to Cei? ^"�^� [he mean grid ooenin5 fiber count for the pcpula*.ion on t��e bd5�5 of thi5 Samplinc. The interval about the samole Tean,'which, ��'.:r 95o confidence, :ontai�s the population mean, is a;so recuired. The distribution of fibers on the qrid open�n�s should theoreti- Cally approximate d Poisson distribution. 6eca��se o` fi�er aggregation and s�ize-dependent Tdent�r'icatior, ef�ects, the fi�er count �ata often do �ot conform to the Poisson distribution, particularly at high fiber co�nts. Sim�;e assumotion of a P�issnn distribution �ay therefer� lead to confidence inte��vais narr�wer than are justified by the data. �oreover, if a Poisson distribution is assumed, the variance is fixed in r�lation to �re total number cf fibers counted. Thus a particular f�ber c^unt conducted on one grid opening is considered to hava the sam� confidence intzrval as that �or the sar.,e number of fibers f�urd cn many qrid openings. Nowever, the area of sample actualiy c•.ur.:eC is very smali in relation to the total area of the filt�r, and f�r this reason fibers must be counted on a mininum of a orid coenino5 taken from different areas of the filter in order to ?ns�re representative evaluation of the deposit. At high fiber counts, where there are adeQuate numbers of fibers per grid opening �o ailoW a saRpla 2stimate of the vari�nce to Ce made, the distributio�� can be apRrax��ated to Gaussian, �Xi�h independent values for the Tean and variarce. ��here the �a�ole estimate of variance exceeds that implicit in the Poisscrian as3umption, use of Gaussian stati5tics with the variance Cefine� b� the actual data is the mo�t conservative approach to calc�lation �f con.`idence in[ervals. �t low fiber counts, it is not possible :o obtain a r�liable saTcie estimate of the variance, and the di5tribution olso becoR�s asyr,�metrfc, but not necessarity �oissonian. For 3C fibers and below, the distribution becomes sufficiently rs��rrnaetric that the G�3ussian fit is no lon�er a reasonable one� an0 sar.ple variar.ce estimates are unreliable, accordingly, for fiber counrs be'ow ?: fibers, the assumption of a QoisSon �is�ri5ution �us: Ce �a�� .`�r ca:culation of the confiden^e intervals. For total fiber counts less than 5, the lower 95: c�nfi�e�ce va�,� �orresponds to one fiber or less, and in addi*ion� tne uo�eY ?��: Confidence value corresaondino to a fi5er count of Zero is ?.�� fibers. Therefore, it is not me�ningful to auote lower C�nf:�cr�� intervat points for fiber ccunts of less than 5, an� the �esu�: should be spetified as "less than" the CorroSoo�dtnq �o�sscn �ce�r 95'; confidence value. � 56 For fiber counts highe� than 30, the sample estimate of variarce is a'so calculatee, and the lar�er of the two corfida_nce in�ervals is seiected. for calculation �f N��sson 95'; conr"idence ;ntervals, , Tabte 40 cr the reference by E.S. rE��rson and H,G. �artley should be used, with an extension to an a.xpectation of 100. Fcr ^ore :han 100 fibers� the Poisson distrib�tion can be accurately approxi:�ate� , by a GausSian distribution, still using the F�isson varianc� esL�mate. For counts of more than 30 fibers, the 95'� cenridence interval based on a sanple estimate of variance is calculated usinc the Student'S "t" distribution. For the two—sided Student's "t" calculation, k values of grid opening fiber count are compared w�t:� - the expected values for the areas of the grid openinos concerned. In summary, fiber counting data �ill te reported as follows; yo fibers detected The value will be reported a� i�_s than 369�= of the concentration eouivalent t� one fiber. 1 to 4 fibers When 1 to 4 fibers are counted, the resulG will be re�erted as less than the corresponding upper 95`� confidence limit (P0155on). 5 to 30 fibers ,Nean and �So confidence intervals �ill be reported on the ba5i5 of the Poisson assu�Gtion. �ore than 30 fibers when more than 30 fibers are count2�, both :he Gaussian 95`� confidence interval �nd the Poisson 95�= co-fi�ence interva� will be calculated. The larger of these 2 intervals :v;ll be se)ected for data reporting, �hen tne Gaussian 95': ConfidenCe interval is SeleCted fpr dat3 reporting� the Poisson interval will also be noted. Fiber counts performed on less than a or;o openin�s yielc very �;;e 95� confiaence intervais when �sino Gaussian s�aristics. This �s be�ause �he value of Student's "t" is very large for 1 and : degrees of freedcm, accordingly, fiber counts Tust not b� �ace rn 1e55 than 4 grid openings. 57 r The samole estimate of variance S2 is first calculated: i = k � (n� - np�)� SZ _ i = I (k - 1) where: n� � N��mber of fibers on the i'th grid ooening n = Total number of Fibers found in k grid oper,ings p� = Fraction of the total area eza�ninec� re�resented by the i'th grid opening k � Number of grid openings for the 95� confidence interval, the valuo of t0.975 is obtained from tables for (k - 1) degrees of freedom. If the :nean value of fiber count is calculated to he n, the uo�er and lower valu�s �f the 95o confidence interval are given by: where: n � n+ts � y � n� = n '�k n� . Upper 95': confidence limit n� � lower 95; Confi�ence limit n �'+1ean number of fiber, Ger grid ooening s � S[andard deviation (square root of Sampl� esti�na:e of varianCe) k � Number e' grid ooeninqs 58 The fiber Concentration in MFL which corresponds to counting of one fiber is giver� Dy: where: AfxRp � �1 x V x 1000 Af = Ef�Qctive fittration dr�a of filter �nembr�ne in mm used for filtration of livuid samole A = Total �rea ex3mined in rrm2 v = Oriqinat volurre of sample filtered (mL1 Rp � Ditution ratio of oriqinat sample The mean concentration i� MFL is obtained by multiolyino the mean number of fibers �er orid ooenirg by kC, To ob�ain the upper and lower 95.'.' confidence l�mits for the concentration �in .�IF�) mul�i�1� the values n� and n� hy kC. 7.3 Estimated Mass Concentration The mass ef each amphibole fiber in r�icrograms is ca�cutaied ��sina the relationship; - whe�e: M- L x'v12 x 0 x 10�6 �� = Mass in microqrams � � Length i n ::m '� = W1dth in :m � � Density of fiber in q/c�r3 59 0 For chrysotile, the mass may be calc:�lated us�r.g the relat�ensni� for a cylinder: M = 4xLxW2xDx 10"° The estimated mass conc�ntration is then giver. b�: where: i = n M� = C x� Mi x 106 i=1 M,. � Mass concentration in ;.g/L C = fiber concentration in MFL, �.rhich corresponrs to counting of one fiber Mq = Mass of the i'th fiber, in micrograms n = 7otal number of fibers found in k orid openings The densities to be assumed are as follows: Chrysotile 2.55 g/cm3 Crocida)ite 3.37 g/cm3 Cummingtonite 3.28 a/c�n3 Grunerite 3.52 g/cm3 Amosite 3,43 g/cm3 Anthoohyllite 3.00 g/cm3 Tremolite 3.00 g/c�n3 Attinolite 3.10 g/cm3 Unknown Amohibole 3.20 g/c�n3 1.4 Fiber �ength, Width, MaSs and Aspect Ratio Distributicns The ��istributions all approximate to logar�thmic-normal, and so the siz� range interva�s for calculation of the distribution must be spaced logarithmicdlly. The other characteri:tics reauired for the choice of size intervals are that they should al'ow `or a sufficient number of size classes, while stili retaining a statistically-valid number of fibers in each class. Interpre�atien is also facititated if each size class repeats at decade intervals. A ratio from one class to the next of 1.468 sztisfies all �f these requirements. The other constraints are that the length distribution should include 0.5 um as one intervat point� since this is the minimum length to be cou�ted in the method, and the rninimum aspect ratio is by definition ?.0, The resulting size classes for the various distributions can be seen in the exam�le shown in Appendix 6. The distributions, being approximately logarithmic-normal, must be plotted using a logarithmic �r�ina�e scale and a Gaussian abscissa. 7.4.1 Fiber Length Cumulative Number �istribution This distrih!►tion allows the fraction of the total number of fibers either ;horter or longer than a qiven lenvth to be determined. It is calculated using the�relationship: where: i=k � n� �(N)k � = N X 100 � �i i=1 �(Nj� = CuR�lat;ve nu�ber percentage of fibers which have lengths less ttian the upper bound of the k'th class � � ni = PJumber of fibers in the i'th tength class' . y N = Total number of lPngth classes bl M 7.4.2 Fiber '�idth Cumulative Number Oistribution This distri5ution allows the fracti�n of the tot�l number of fibers either narrower or wider thdn a given width �o be � determined. It is calculated in a;imilar way to `hat used in 7.4.1 for the len5th di5tribution. 7.4.3 Fiber Lenath C��mulative ��ass Distribution " This distribution allows the fraction of the total mass incorporated in fibers either shorter or longer than a give� length to be determine�. Tt is computed using the relationship: i =k j =n� � � l�w� ` i = 1 .7 = 1 �(M�k i= N j=;�i x 100 � � l���z i = 1 j = i where: C�M�k = Cumulative mass percentage of fib�rs which have lengths less than the upper bound of the k'th class n� = Number of fibers in the i'th length class 1� = Length of the j'th fiber in the i'th length clas� w� _':Jidth of the j'th fiber in the i'th length class N = Total r�umber of length classes 7.4.4 Fiber Aspect Ratio Cumulative '�umber Distribution This distribution aliows the fraction of the total nurber of - fibers which have aspect ratio� either smaller or larger than a given aspect ratio to be determined. lt is 62 � • calculated in a similar way t� that used in 7,4.1 fcr �ha tength distributian. 7.4.5 Fiber Mass Cumul�tive Number Dis�ribution This distribution allo��s the fraction of the total number ' of fibers which have masses either smaller or laroer than a given mass to be determined. 1t is calculated by placing the f�bers into loqarithmically-spaced mass cateqories, after which the cumulative frequency �istribution is obta�ned in a similar way to that used in 7.4.1 for the " length distribution. 7.5 Index of Fibrosity It is possibte to discriminate between anphibole asbestos fiters and amphibole cleavage fragments on the basis of the distribu�ion of their aspect ratios. The concept of fibrosity in a miner�l embodies a high median aspect ratio, together with a large �predd of aspect ratios above the median value. A single number can be used to describe the fibrosity of a mineral fiber dispersion, and in many cases the value can be used to state if the mate,�ial i; or is not asbestos. The fibrosity index can be defined thus: F�R9 wher� R is the median ot the asoect ratio distribution and q is `he geome�r�c standard d2viation of thz aspect rat�o distribution above the median. The value of g is obtained from th�t portion of the distribution lying between one and two georretric standard deviations above the median. Meaninqful values of the index of fibrosity can be obtained for most waterborne fi�er �isoersions if jmore than 50 fibers h;ve.been measured. The fibrosity index as def;ned above has values exceedina 100 for waterbcrne dispersions of asbestos. Values below SC indicate a distribution characteristiC of cleavage fragm�nts, or o�e from which the hiqh aspect ratio fibers have been ;electively removed. 8. REPORTING The computer progrjm provided in .appendix B satis`ies all of �he reporting requirements for this anatytical metnod, �nd it is reccmrrended that this format be used. The size classifications used must be the sar�e as those in Appendix B. 63 . V 8.1 Before tre fiber count data can be processed i� qive conCentr3ti0n values, a d�cision must be �ade as to which fiber classifications ar� to be considered adequate as identification of the fiber species in question. This decis�on �ill de�end on how much is known about the particular Source from �Nhich the sam�le was collected. For a sample from a completely uncharacterized soures, tne fol�owing procedure will be used to accumulate the classified fibers: a} Confinned Amph�bole: AllQ t AZQ * All (solutions must incl�de onl� amphiboles) b) Amphibole Sest Estimate*: AllQ + AZQ + All + aZ + AoQ + aQ c) Suspected Amphibole: ADX + AX + AO d) Confirmed Chrysotile: coq * Cd e) ChryscLile 3est �stimate*: CDQ + CO + C�tQ + CC f) Suspected Chrysatile: CM *NOTE: Best estimate can be reported only if some fibers are also reported in the confirmed cateqory, oth?rwise all fiber classifications must be reoorted as suspected amnhibole or chr�sotile. 8.? The concentration in i�iFl, together with 95� confidence intervals, wili be reported for the groupings in Section 8.1 (a) to (f). 8.3 Two significant fig�res �vill normally be used for cencentrations greater than 1 MFL, and one significant figure for concentrations less than 1 MFL. 8.4 For confirmation of chrysoti�e, a micrograph and a calibrated diffraction pattern will be provided from a typical fiber. The identification features in Figure l� must be visible on the diffraction pattern. For confirmation of amphibole, either (1) or (2) or (3) below �ust _ be provided for a typical fiber of each amphibole variety = reported. The data provided must yield solutions which irc,ude only amphibole. . r 1) A micrograph, a calibrated zone axis SaEO pattern, and an EDXA spectrum toge�her with po_ak area �neasurements and EDXA calibration data; 64 2) a microqraph, and two calibrated zone axis Sa�C patterns with a�easurement of the anQular r�ta'�on between the two o�:[terns; � 3) A micronraph, twn ca ibra�e� zo�� axis S�c� Ddtt?rn5 with a �:easurement ot t��e anq��iar ro'���ticn het�NQ�n `he � two patterns, and an ED"? spectr�;m tc�ether with ceak area reasurements and EDX,� calibratio,� data. 8.5 Tabula`_e the length, wid�h ar,d aspect ratio distributions. � 6.6 Report '.:he estimatrd mass conce�tration in �g/L for each of the grouaings in Section 8.1 (a) to (f). 8.7 One significant figure will normally be used for report�ng mass concentration. 8•8 Report the concentr3tion.in MFL co�resoonding to one fiber detected. 8.9 Report the total number of fibers counted in eacn of the groupir.gs in Section 8.1 (a) to (f;. $.10 Report the X2 value for ea�h of the groupings in Section 8.t (al to (f). 8.11 Report t��e nu��ber of fiber aggregates not included in the fiber count 8.12 Report an� specia'. circumstances �:�r cbservations s�ch as aggr�gation, presence of organic mat�rials, amount o; �ebris, presence of othe; fibers and their probable ident;�y ;f known, 9. l I hI TAT IONS Of ACCURr1C Y 9.1 C;�rors and Limitations of Idertification Complete identiPication of every chrysotile fiber is not possibie, due to both instrumental limitations and the nature of some of the fibers. The requiremen� for a calibrated SAED pattern eliminates the possibility of an incorrect identification of the fiber selected. However, there is a possibility of �nisidentification of other chrysotiTe fibers for wh?ch both morphology and SAED pattern are reported on the basis of visual insaection onl�. The cnly significant possibilittes of misidentification occur with halloysite, ve r,niculite scrolls or palygorskite, all of :vhich can be discrimina�ed from chrysotile by the ;:se of �OXA and bv observation of the 0.73 r,m (002) reflection of chr�so'_ile in the SAED pattern. as in the case of chrysotile fibers, cemplet� id2ntir;cstion or � every amphibole fiber is not possible due to ins�r;,mental 65 � limitations and the nature of some of the fiber5. ��oreover, complet: identification of every amphibole f�ber is usually noL practical due to limitat�ons of both time and cost. Particles of `�A number of other minerals having camp�sitions similar to those of some amphiboles could be erroneously classified as amphibole Nhen the classification criteria do not include zone axis SAED � techniques. However, the requirement for quantitative E�xa measurements on all fiber; as Supoort for the random orientation „. SAED technique makes misidentification very unlikely, particularl,✓ when other similar fibers in the same sample have been identified as amphibole by zone axis methods. The possibility of misidentification is further reduced �ith increasing aspect ratio, since many of the minerals with which amphibole may be confused do not display its prominent cleavage parailel ta the c-axis. 9.2 Obscuration If large amounts of other materials 3re present, some asbestos fibers may not be vbserved because of physical overlapping. This will result in low values for the reported asbestos content. 9.3 Inadequate Dispersion If the initiai water sample contains organic material which is incompletely oxidized in the ozone-UV treatment, it wi11 not be possible to disperse any fibers associated with the organic material. This may lead to adhesion of some fibers to the container walls and aliquots taken during fittration will then not be representative. It may also lead to a larqe proportion of fiber aggregates Nhich are either not tr�ansferred during the replication and fi]ter dissolution step or which cannot be counted during the sample examination. The result obtainEd from such an analysis �H.11 be low. The sample will also be inade4uately disoersed if it is not treated in an ultrasonic bath prior tc filtration, and therefore instructions regardiRg this treatment must be followed closely. 9.4 Contamination ' Contamination by introduction of extraneous fibers during the analysis is an important source of erroneous results� particularly for chrysotile. The possibility of contamination, tharefore, should always be a consideration. 9.5 freezing 7he effect of freezing on asbestos fibers is not known but ttiere is reason to suspect that fiber breakdown could occur and result in a higher fiber co�nt than was present in the oriQinal sample. 7herefore, the sample should be transported to the lshoratory and stored under conditions that will avoid freezing. � 10. PRECISIaN aND �CCURaCY 10.1 Generai The precision that can be obtained is dependPnt upon �he nu�oer o.` fibers courtted, and on the uniformit� of particulate deo�sit on the original filter. If 100 f?bers are counted �nd the ioadina is at least 3.5 fibers/grid square, c�mputer modeling of the countinq . procedure shows that a relative standard deviatior, of about 1C�� can be expected. As the number of fibers counted decreases, the precision will also decrease approximately as �V where N is the number of fibers counted. In actual practice, some degradation from this precision will be observed. fhis degraCation is a consequence of sample preparation errors, non-unifo mity of che filtered par*icuiate depo�it, and fiber identificaticn variability between operators and between instr�ments. the 95'a confidenc� interval about the mean for a single fiber cnncer�tration mea�urement using this analytical method should be about j25'; when about 100 fibers are counted over 20 grid ooe��ngs. For these conditions the precision of the cempu:ed mass concentration is generally lower than the precision for the fiber number concentration. The precision to be expected for a single determination �f mass concentration is critically dependent on :he fiber width distribution. For a result oased on �easurernent of a minimum of about 100 fibers, the 95'� confidence interval about the mean computed mass concentration may vary between ;25-; and =60`:. If better precision is reauired for a mass dete rnination, the alternative counting method described in S?ction 6.5.5 should ae used. 10.2 Precision 10.2.1 Intra-Laboratory Ccmparison Using cnvironmental �ater Sources Tabie 6 shows the results obtained from analysis of 10 replicate samples from each of 8 water sampling locations. rour of these locarions were associated with a source of chrysotile and four associated with a source of amph�bole. It can be seen that the relative standard deviations of the number concentrations range between 13� and 22`�. The corresponding relative standard deviations for �he mass concentrations range bet�Neen 29`� and 69°�. 10.2.2 Inter-l.aboratory Comparison of Filters Pr�pared :�si�g Standard Dispersions ard Environmental 'Nater Sources Tabies 7 and 8 show the fiber c�unting result� ob�ained «hen sectors of filters prepared in the ORF Labora�ory were distributed to six laboratories considered experienced in asbestos analy5i5 by the identification and countinq techniques incorporated in this manual. The samples as 6�7 q _ 7 f � � ., p r ( ' C L .� ] � � . . . ' J v a ! � � V T � � ? ^�5 v ' I Z ` � I ' ' t ^ � L ( � O � L � y '.� � ' t � r � � � m { � � L O ^ ( : . � .1 ` I � � . a .+ .� N s+ N u 7^ W O� ^ ,J T I N q Q r1 .p N Q �O V O > � J J ¢ �n o � � g v I ; Q s a � u N 7� c � v o o ' v 9 �. i � = I �"� N N 9 T [[ C � � � � O C � ( � � O� N ' W � O � , � ' � � � ; y � � � � j � C i J J .� .. � +1 C Q � �L 7 � � �' 1 ^� � 3 � �, N—. . . . . . � � J � o' _' P ' o 0 0 o i a 1+ — � � U y � Q , � I � ' rv 7 � Z � i V� C ' 1 f1 = '. ( 1t b ' � '! � L � N ti .� C � .L1 . Z � i S O �i O O � � L c�. � a � 1 d C � ' � � I � a .+ - � . .w ie .. t� . . Z � 7 .9 � � � � � C� � ~ ��; ��I � " I — � s �.+ � �� O ^y � i � I 1 � I ` i J � � 7 J •�Cj I "J, � � I - � � T (,/) � 7 ..• ' ]D a � � t ]o C • V , � v �! .A ��1 I '� � � � d' � ( � a � � � , � � . � � � Q c � � � _. -, I 4 ' j � .� = � �o o .n � , Q, � � � j �: � � �� � I .t+ � 'T'� �l � N � .�+ 9 < N OV j � I:L a � � I � y = i � � � I� I � - ri T c f. ~ , � � � • �� � I . . � . � . T � � . 2 � 3i � T � � v . J T .n . � Q I J I T .� V i : [G 1 � O co � I . 4 � J : = i � � o � � � ? o o � o Z ' � i ` r I � I � +� � I i �p a ' v i+ c . - I 7 > > � n '� � � (y,� f J + � 7 S � 7 .� � J I T � ✓ — � ... O�] � = v ' i .J v :� - � - I J 1 - � l ~ � .� � 3� � � y j �i i' .+ � � , `^ � '3 � ' .. , x � � �: � s i � : i I I ! � � I = j n � �� y I - i � 1 . o o � i ° � = I �c - ^ - v .'' I3 e 7 ' ^ I �a . ` .� y1 I •J � ' � i i I o � � � • `'_'------- t _ y . � J�] - I 'T 'p ,n � i . . ' � � 7 �O ,n y� M e ; r � � V � . 1 � • 2 . r i � _ � ' 1 ' •t I _ L = � J � ( L � L^ I � ry � � . ^-�' o i 7 q T 'n .�n ,A 0 � � ' n f �� I ,C L , ^ ~ � � � � I ` T ^ . ] p � � � � o C i � � v � � N � ' + � ' N . i � � ' _. x � a � = ' _ . o ;,, . � � • "'� � T � � O 7 �+ � Q � ' � � � T A n W! � � ^ o �o � � . . � � ' I • � � �" � �. � . C/') , � � ' 7 n 7 ' �— � .v, ' � m .� e '3 � '� a �, Q� � 'y .r ', ' ^ ^ 'n x' � ' � . ' � � � � � Z . � � ' Z � Q ' � � ' F-• ! ,� ; , 1 : i H ' '� � I a; �� r � "+ a ,s e .a o '" L . . Y ' � � � � � a � � � _ r a ^ � ^ � Z ' ^ - ' o ..y, � � � � . . a • o O � j ; �� � � � a a ^ N � ` � �' I I V � T I � ; � y S � • _ � Q ' � 2 � � 1 � � � i � F ; Q N ^ O C . J , ti . v . � ' ti � :� �. � = ; . > ' , x I i , O • � ' F— . ' o , •� � . � � � ' y ^ ' � � �' m c � � _. - z� � � �..� .n � � � _� � - � ..� Q , ; F ' i . ' . �-�---_-�'"--� ��---�-��� . �' � I ' � = . W �' ' L^ ^' h 7 1 � . . � S � 9 � 7 C I � � = � , i z ' � � r " y � :-�`' � � N � .� � ^ " � i 1 o r ^ ,� `. ^ ^' , �' c � ^ 6'� � T Q O� '� '� ... � �` C .7j . 1 ' �-_ � j w � I � z � . J � a "' e N � T . tl � a Q, = � . , . d ' � i �• ,a � F- � • � i . I 1 � ,i • � , - i � , n . . � � - J ' � � � � � � 7 ? O 7 3 � ' � � y ' �.'�J � ^ ~ ^ V `n O / L � � � ^ L � � j y � N - . . V ` L � . ! � • � i . � � � � L 7 � > � J . _ E .n S .� 59 F � � i � N 'G � L. L. y! rry "'� t0 O'� N W a� a.+ .-. Q r� r� r� r� � .a G .'+ � �+. ) Z U u�, v G .� � r., v a� �o o cn a u. c ^ �... � y � • � N N N • "" N CL _ ��C N r� CA �L � ^"' Q� Q � 4J C •r > ^' W J 9 C y,. L ('� C� � ,n � c/1 O C CJ � 1 � � � � .-. N L •u C> � tD O � N N � N , N•p O f'7 T N n U L T� � ++ � O'+ t'1 v �f'f C� O W � � M.-� CJ ,Q v 3 p r� O a7 t� r� J C> C �O CO ••• n ^+ N Qip . . . • �, � o t,ii �c �o tn �c z '� W � Z y„ O � L 6J 5 � i . 6! a� .� Ci � C CO � Q� tl� O'+ w��� � � N N C") .-+ M E 4. O � U _ _ � � ' C a � a M M tD Q� Q� � ^ � �^ I 4. C� N M ?� C Q' O 0 I � � Z7 ; N N N N � N ^ r � �"� ip L' V- 1 1 t I 1 1 � Q '.`� +'. �„ N O C tU �'n ... � y,i � ,.w �p .-� M N � O C�.i O� V� .-� tp r'� O �D t0 Z � I L N � O ^�+ N O O ..+ u'f q c rn m � ¢ -► pC C ... n. .., p .� c�1 C �"'� �C n �' �. �. � '�? � ty � .-� �+ N N �-' ^ H � Z .^. a..� C13 9 > :d W fj +� J � L Ca ^ C O d O O � a � T . L O w �p ..r (V M Q L O � A J �� � � � � � � � 4 X J 9 '3 C N �f'� �L> � .� 7 V 37 C.'J a..� . � y � N v v a - "a a � 6 > N V t '� `7 a.� L c c ro � v � � � � y • ;� cn s � distributed were identified 5y n�mher pnly, ;� -ah1e 7 i� can be seen that the r^lative standar� deviations for ?he Six results on each of the stan�ard dispers;�n fi�te�s ��c r.ot exceed 27a. In Table 8, the environmental ��ater " sources useC to prepare the filter samples containee similar types of suspended materials as those usec to generate the intra-laborator� resul[5 �n Tab'e 6. i�e re)ative standard deviations do not exce�d 29";, which appears higher than the values obt3ined for the � intra-laboracory res�lts. Nowever� when the 6 inter-laboratory results are compared �ith the 10 intra-laboratory vatues, there is no stat�sticall� Sionificant difference to indiCate that there has 5e�n �n� degradation of precision. 10.3 Accuracy 10.3.1 Intra- and Inter-Laboratory Ccmparison of Standard Dispersions of Asbestos Fibers Tables 9 and 10 shoM the results obtained betNeen two taboratories when stable aqueous �iber disporsions of kncwn mass Concentrations �ere anatyted. The fibo.r conCentrations reported displayed no siqnifi�ant differance between vaiues frcn the t�o iaboratories. The relativ� standard deviation of the mean fiber concentr�tion was 17", for chrysocile an� 16�: for crocidotite. The CorreS�G�Cing relative Standdrd deviat�on5 `or the mas5 ConCentration were 16�� for chrysotile, and 37�; for croc��o�ite. ;h� highe� variability for crocidolitp �s a consecuence of the lcw statistica� reliabit;ty of the �arqe diameter fi5er counts. The computed mean mass conce�t�aticn for chrysotile was about 46�� hi�her tha� ��e knpwn mass concentration. This �ay be a consequence o` the d�ff�c�;*v of diameter measurement for sinqle chrysotiie fi�rils �r � the assumption of the bulk value for the �ensi�y. The computed mean value for �ass concentra�ion far tne crocidolite sample was 67.a �qIL, which is very cl�se to the k�own concentration of 50 �gJl. 71 z 0 � � W 0. N W ..�. � M-- Q' W v'1 m � � � U W ..^-�. F- 2 O O � _ r ct — ¢ v` G � J V C� r ` � o O n+ � � � Q J O � W r- r- � U C J Q W � i W O � z y � � J Q1 Q W a � � a r �� I � ; � �.. � i � o� � , Lu � � .... o rn � Q Q � ,�� � , I ,Q � r. r» , C L I ' � � GJ � I i zr � . � ( i I � � , � � � I I N C I � 1 1 � ra O I � • ~ � . � I 1 L\ Q� �"� t�f� � G � i l"1 t!� .D � J a.i Q1 � P� Q C'7 � �D Q� � :V � �O C G ^' ^' ^' I ^ 1 I � y : � � I ' � C i I f � � � I ( W v � . t - - — ' I ( � � I I �O y L J �JJ W V � ►c. u'+ x � tA Q' N C Cl N N N O V � i i � +� J � Iep � � tt1 T �D L � �D et �O .�-i w ... .--� I� � v o � � v o � •' :1 N'1 � L 1 � .G u. I C O �+ � tO �+ O� Q� I� N � �. CJ a v N � �o � � a L O rJ h , ( �O .-. �6 J � � c c � 0 0 � o ; � ..+ �o •— � �O A � � I L •-- C �O u > rp � C :J ++ > • v � N � I C � ^ I O U � '� c �n �O �o ^ � i � v� � � z W p ..~... N _J C 8 W 4 .., N c� �-. O O � U C W n O � N'1 W H s � J � � O v � > � � � C f" J d' Q1 C] 3 Q C J l.C) � ¢ •-. �„ � L' O W Q Q ..V. 1 W � ►"' W Z CC •--' LL O O r W L!1 J �- d J 1�- _ Q � a L � Q � � U 'JO � tA � � d 'n N r+ � d � � i ^ ^ . ^ I z � , ti I � � � I i 1 . N ' i � N C iC O � i E •� '� � ! � � � � J Sr L� ( O Q �7 ; p .-. i Q. ,-.� - � � M Q � 1� �1'ry C") � a C � 01 m � ' � � � N � c G I� u ' � � � N O W G..1 I � I � i I '-- I ' , a � i L � I I � :; i i i � ..-. � i.r. � � r„� Q� I C C� .-�+ t� n � �7 N � ^ N 1: � o v ' A � � , ' , � ' ' I � u L � � � I N C� i �.r � ..+ �-�r � ! P^f � � � 1 C � I � � � � � � I I � " i I p�`, i ; I � ti `a i V i � I i ` � t � , I� ta. C CC P"� �,p ( 'O � � � � �� � � � I � � i 1 I 1C Q Q Q �D � ^'� N f") N f � O 0 L O G A J ,) 13 �� ti ♦ � � SEIECTED B.BLIOGRAPHY :` Anderson, C.H. and J.M. Long (1980). Interim Metnod for Determinin9 Asbestos in Water, Report EPA-600/4-80-005. 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