NYC-WTC_000196110

NYC 9/11 Public Portal Document

ATC ASSOCIATES INC PAGE 02/03 03/17/2001 00:36 2123533599

ATC ASSOCIATES INC. NOB ANALYSIS Balch No. Grid fiox No. Operator

Sample No Q -/ Grid I.D. Date -9. Grid Structure su-jcoue Electron x-Ray Identity No. Nd. DiffracUon. Remarks F B C .M Obaervation Observatioo Chrysotile Amphibole

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lOis T F= Single Fiber (1-3 intersections = 1-3 fibers) amphiboles B= Bundle (>3 fibers <1 fiber diameter apart) Amosite C= Cluster (>3 intersections) Crocidolite M=: Matrix Anthophyllite Tremolite NSD= No Structures Detected Actinolite

= Positive diffraction pattern observed conforming to identification criteria. For chrysotile; 7.3A spacing for 020 reflections (= 60um objective aperture). 5.3A spacing for the layer-line repeat (= 1/3 SOuxn objective aperture), 110 and 130 streaks and presence of 002 and 200 reflections. For amphiboles; 5.3A layer-line repeat and approximate 3.5 ratio of non-tthnned layer-line retTsction spacing to layer-line repeat distance.

yZ= EDX spectrum obsei-ved conforming to identification criteria'. Mininaum Requirements: Identify 4 fibers by electron, diffraction. Chrysotile: 5.3A layer-line (ro-rr) spacing ■<vith correct 020. 002. 110, 130 and 200 points or streaks. Amphibole: Correct 5.3A layer-line spacing. EDX Requirements; Chrysotile; none. .Amphibole: identify amphibole species by EDX.

QU.4mTrAT10N; Estimated Percent Asbestos on: Grid 1: Grid 2: Mean (N):

Percent Asbestos in Subsample: (N X K)/G:

From PLM NOB ANALYSIS SHEET: 10 X 11 = 14 where 10 = total residue %. 11 = residue asb % TEM and 14 = total ?! asb &: typ®- Also, 1% total asbestos = lOO/total residue %.

CITY_21MC100_003054643

NYC-WTC_000196110