Forwarding WTC air monitoring scope for final review, Aug 2002

NYC 9/11 Public Portal Document

Environmental Protection Agency n. 763, Subpt E, App. A 8, Perform a systems check on the trans­ tron Microscopy Using Polycarbonate Mem­ mission electron microscope dally. brane Filters.” WERL SOP 87-L March 5, 9. Make periodic performance checks of 1987. magnification, electron diffraction and en­ 9. NIOSH. Method 7402 for Asbestos Fibers, ergy dispersive X-ray systems as set forth in December 11, 1986 Draft, Table III of Unit III.K. 10. Yamate, G,, S,C, Agarwall, R,D, Gib­ 10. Ensure qualified operator performance bons, IIT Research Institute, “Methodology by evaluation of replicate counting, dupli­ for the Measurement of Airborne Asbestos by cate analysis, and standard sample compari­ Electron Microscopy,” Draft report, USEPA sons as set forth in Table III of Unit III.K. Contract 68-02-3266, July 1984, 11. Validate all data entries. 11, Guidance to the Preparation of Quality 12. Recalculate a percentage of all com­ /Assurance Project Plans, USEPA, Office of putations and automatic data reduction Pollution Prevention and Toxics, 1984. steps as specified in Table III. ZV. Mandatoiy Interpretation of Transmission 13. Record an electron diffraction pattern Electron Microsct^ Results to Determine of one asbestos structure from every five Completion ofResponse Actions samples that contain asbestos. Verify the Identification of the pattern by measure­ A. Introduction ment or comparison of the pattern with pat­ terns collected from standards under the A response action is determined to be com­ same conditions. pleted by TEM when the abatement area has been cleaned and the airborne asbestos con­ The outline of quality control procedures centration Inside the abatement area is no presented above is viewed as the minimum higher than concentrations at locations out­ required to assure that quality data Is pro­ side the abatement area. “Outside” means duced for clearance testing of an asbestos outside the abatement area, but not nec­ abated area. Additional information may be essarily outside the building, EPA reasons gained by other control tests. Specifics on that an asbestos removal contractor cannot those control procedures and options avail­ be expected to clean an abatement area to an able for environmental testing can be ob­ airborne asbestos concentration that is tained by consulting References 6. 7. and 11 lower than the concentration of air entering of Unit III.L. the abatement area from outdoors or from L. References other parts of the building. After the abate­ ment area has passed a thorough visual In­ For additional background information on spection, and before the outer containment this method the following references should barrier Is removed, a minimum of five air be consulted. samples inside the abatement area and a 1. "Guidelines for Controlling Asbestos- minimum of five air samples outside the Containing Materials in Buildings,” EPA 560/ abatement area must be collected. Hence, 5-85-024, June 1985, the response action is determined to be com­ 2. “Measuring Airborne Asbestos Following pleted when the average airborne asbestos an Abatement Action,” USEP/Office of Pol­ concentration measured inside the abate­ lution Prevention and Toxics, EPA 600/4-85- ment area is not statistically different from 049, 1985. the average airborne asbestos concentration 3. Small. John and E. Steel. Asbestos measured outside the abatement area. Standards: Materials and Analytical Meth­ The inside and outside concentrations sire ods. N.B.S. Special Publication 619, 1982, compared by the Z-test, a statistical test 4. Campbell, W.J„ R,L, Blake, L.L. Brown, that takes Into account the variability In E.E, Cather, and J,J, Sjoberg. Selected Sili­ the measurement process. A minimum of cate Minerals and Their Asbestlform Vari­ five samples Inside the abatement area and eties. Information Circular 8751, U,S, Bureau five samples outside the abatement area are of Mines, 1977. required to control the false negative error 5. Quality Assurance Handbook for Air Pol­ rate, i,e., the probability of declaring the re­ lution Measurement System. Ambient Air moval complete when, in fact, the air con­ Methods, EPA 600/4-77-027a, USEPA, Office of centration inside the abatement area is sig­ Research and Development, 1977, nificantly higher than outside the abatement 6. Method 2A: Direct Measurement of Gas area. Additional quality control is provided Volume Through Pipes and Small Ducts, 40 by requiring three blanks (filters through CFR Part 60 Appendix A. which no air has been drawn) to be analyzed 7. Burdette, G,J. Health & Safety Exec,, to check for unusually high filter contami­ Research & Lab. Services Div., London, nation that would distort the test results. “Proposed Analytical Method for Determina­ When volumes greater than or equal to tion of Asbestos in Air,” 1,199 L for a 25 mm filter and 2,799 L for a 37 8, Chatfield, E,J,, Chatfield Tech, Cons., mm filter have been collected and the aver­ Ltd,, Clark, T,, PEI Assoc. ‘’Standard Oper­ age number of asbestos structures on sam­ ating Procedure for Determination of Air­ ples inside the abatement area is no greater borne Asbestos Fibers by Transmission Elec­ than 70 s/mm^ of filter, the response action

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