Asbestos analysis methods for carpeting samples, 1993

NYC 9/11 Public Portal Document

a . PB93-194355

ruHi \_____________ EPA/600/J^93Z16Z

Methods for the Analysis of Carpet Samples for Asbestos James R. Millette. I’b.D./ P. J. Clark. ” , Kim A. Brackett, I’h.D., C and R. K. Wheelcs'^

(Key words: Asbestos, Transmission Electron Microscopy (TEM), Carpeting, Ultrasonic Treatment, Miaovacuum} I NTtS Iswtiioriiea to reimiilucs art tall nit 1 I noort. Permlssloa lor tatUtr lepodnstloo 1 mild ba abtatnail Irani Iba cooyrUftt owner.

Assessing asbestos fiber contamination in a carpet is (HEPA) niicrcd vacuum cleaner or a hot water extraction cleaner complicated by the nature of the carpeting—because of (steam cleaner). The potential Tor airborne asbestos fiber the pile's rough surfoce and thickness, sranples cannot be reentrainment during carpet cleaning activities was shown in studies in which airborne asbestos concentration!; were found to be collected directly from carpet for analysis by TEM. Two between two and four time.s greater during cleaning than before the indirect methods ore currently used by laboratories when carpet cleaning activities.-- ___ preparing samples for measuring the amount of asbestos There arc curren tl y two methods used by the authors' labora- j ! present in carpet material. One is an ultrasonic shaking iorie.s forcollectingand indirectly preparing samples toevaluate the 3 X technique which requires that a portion of the carpet be cut amount of asbestos in or on a carpet. Direct collection and direct preparation procedures such a.s tape lift sampling have been ||s out and sent to the laboratory. The other is a mkro- investigated and cannot be used efTcctively with carpeting. There |dl| ; vacuuming technique which has been used generally in the arc currently no standard EPA mcihod.s for a.sse.ssing asbestos in |l|l ' assessment of asbestos in settled dust in buildings. It is not carpeting. One of the rricthods which is used is an ultrasonic ’ destructive to the corpet. Both methods utilize TEM to extraction procedure in which a square piece cut from a carpet i.s identify, measure ond count the asbestos fibers found. Each mildly sonicated in water with surfactant to rcletise asbestos fibers both on the surface and embedded in the carpet. This method i.s con provide important but different information when an similar to one that hxs been published about how to measure — assessment of the level of contominotion of carpeting is asbestos fibers in clothing and fabric materials.’’ The other method being made. The ultrasonic shaking (bulk-carpet sonication) is’ a vacuuming procedure which uses a modified air sampling technique gives an index of the asbestos contamination cassette to vacuum a sample of dust primarily from the surface of throughout the entire carpet piece and the micro-vacuuming the carpet. The microvacuuming technique is non-destructi ve to the carpet. Both mcihod.s use the panicle dispersion techniques devel­ technique gives an index of the readily releosable asbestos oped over the years for the analysis of asbestos in drinking water.^-* fiber from the carpet surface. The Ultrosonk Preparation Procedure major concern in buildings that contain a,sbc.stos-con- taining material (ACM) i.s the extent to which the carpet Samples of carpel arc collected by cutting a piece (usually 10 mayserveasarcscrvoirofasbcstosfibcrsthathavcbcen centimeters by 10centimeters) from the carpet with a razor blade rclexsed from the ACM by one mechanism or another.* The or utility knife and placing it in a wide-mouth polyethylene jar or ■ Asbestos Hazard Emergency Response Act (AHERA) requires zip-loc bag. In the laboratory, five (5) centimeter by five (S) chut all carpet in areas of school buildings in which ACM Is ccntimetcrsquaresofcarpetarecutandplacedcarpet-sidedownin present be cleaned with either a high-efficiency paniculate air a 1,000 milliliter beaker containing 100 mjlliUtcrsofO. I % solution REPRODUCED BY U.S. DEPARTMENT OF COMMERCE Envirennuntol Oieites Tedinicol Supplenent • Mordi/April 1993 NATIONAL TECHNICAL INFORMATION SERVICE 21

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