NYC-WTC_000220345

NYC 9/11 Public Portal Document

Clean Air Testing Labs. Inc. nil Steele Blvd. Baldwin, New York 11510 Tel./Fax; (516) 646-2640

(TEM) P.PA 600/P.-9t-116-C.haffield Sp-mi-Qiiantitafive KPA .16-Qnantitative NYS DOH KT ■ AP 1Q8 1 (PT M)/1 Q8 4 (TEM)

All Non-Friable Organically Bound (NOB) samples are analyzed per NYS DOH ELAP item 198.1 (PLM) and 198.4 (TEM) when negative by PLM. Other samples as requested shall be gravimetrically reduced prior to slide preparation. This method is particularly useful to reduce the possibility of false negatives for levels of asbestos. Asbestos fibers may be present in some non-friable materials, but may not be detectable by PLM, due to their small size or interference from binding materials. If routine PLM analysis finds the sample to be nan-asbestos containing material or containing asbestos in low concentration levels, the tile confirming problematic samples (floor tiles, roofing, etc.) that actually contain many small of organically bound asbestos fibers which cannot be detected by PLM. It can also be used to quantify very low levels of asbestos (0,1 %. by weight or less) on some types of bulk samples.

In New York State, non-friable organically bound. (NOB) materials determined to be negative (< or =1% asbestos) by PLM must be analyzed by TEM before the sample can be officially considered as non-asbestos containing material (ACM). ,EPA recommends that floor tile reported as negative by PLM should, be analyzed by a new EPA method utilizing TEM. Clean Air Testing Labs, Inc., uses ELAP method 198.1 (PLM) and 198.4 (TEM) for New York samples. Samples from other areas are evaluated by a similar modified Chatfield, 'TEM protocol that is pending ASTM Committee D22.OS.07.007 approval (submitted by Eric Chatfield, 1988), The method leads to the identification of any asbestos minerals (fibers) present within the sample, as well as giving the weight percent. All asbestos■minerals .are identified on the basis of fiber morphology, energy, dispersive x-ray spectometry (EDS), and selected area electron diffraction (SAED). Following the matrix reduction digestion procedure, floor tile inert residue usually contains only pigments such as titanium dioxide and/or iron oxides, fillers such .as silicate or aluminosilicate minerals and asbestos if present. Other bulk materials■may contain additional inert materials. A modified method of the aforementioned is used when analysis is required of non-friable materials. The laboratory has been approved to analyze these samples by the NY State Department of Health Environmental. Laboratory Approval Program (ELAP) Laboratory ID # 11242.

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