PCM fiber results, 100 Church Street, Mar 2002

NYC 9/11 Public Portal Document Sci b#: 202032410 ra ui

Client Name: TRC Environmental Corporation Phase Contrast Microscopy (PCM) Fiber Results 35052-0000-00007; New York City Law Department; 100 Church Street/ Ambient Flow Air Fiber Fibers SciLab Client Rate Duration Filtered Density Cone. TWA Fields Fibers Sample # Sample # / Location Collected (liters/min.) (min.) (liters) (Fibers/mm"^ ) (Fibers/cc)

01 GS-3/12/02-ASB-0353 3/12/02 5 240 1200 100 2 2.55 < 0.002 Rm 3-234 02 GS-3/12/02-ASB-0354 3/12/02 5 240 1200 100 1 1.27 <0.002 Rm 3-182 03 GS-3/12/02-ASB-0355 3/12/02 5 240 1200 100 3 3.82 < 0.002 Rm 3-184 04 GS-3/12/02-ASB-0356 3/12/02 5 300 1500 100 2 2.55 < 0.002 Rm 3-110 05 GS-3/12/02-ASB-0357 3/12/02 0 0 0 100 0.5 0.64 Field Blank Footnotes: 1 06 GS-3/12/02-ASB-0358 3/12/02 0 0 0 100 0.5 0.64 Field Blank Footnotes: 1 Reporting Notes: (1) Fibers/cc cannot Jje calculated for samples (or blanks) with no air volume. Analyzed by: Devin Ahyee XZO^***- ; Date Analyzed: 3/14/02 Samples analyzed by NIOSH 7400(A) Method. Issue #2, 8/15/94: Limit of Detection^ 5.5 fibers per 100 fields or 7 fibers/mm2: This report relates ONLY to the sample analysis expressed as fibers/sq mm of filter area: ND=No fibers observed: NA= Not Analyzed; Walton-Beckett graticie field area = 0.00785 min2: TWA = 8 Hr TWA calculation assumes zero exposure for remainder of 8 hr period not sampled: Upper 95% Confidence limit (Employers Compliance Test)-'Calculated as a one sided UCL to determine 95% certainty of compliance with the 0.01 fiber/cc standard: Estimated relative standard deviation; Intralab Sr=0.405, Interlab Sr=0.45, New York samples (NYSDOH ELAP Lab # 11480); National Institute of Standards and Technology Accreditation requirements mandate that this report must not be reproduced except in full without the approval of the laboratory. AMA # 102843.

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