PCM fiber results, 100 Church Street, Jan 2002

NYC 9/11 Public Portal Document

Sc b#: 202013652 jra UI

Client Name: TRC Environmental Corporation Phase Contrast Microscopy (PCM) Fiber Results 35052-0000-00004; New York City Law Dept.; 100 Church Street Flow Air Fiber Fibers SciLab Client Rate Duration Filtered Density Cone. TWA Fields Fibers Sample # Sample # / Location Collected (Uters/min.) (min.) (liters) (Fibers/mm^ ) (Fibers/cc)

01 GS17 1/31/02 3 30 90 too 8 10.19 0.044 Mario Davis 02 GS18 1/31/02 3 30 90 100 4 5.10 < 0.030 Ceasar Rodriguez 03 GS19 1/31/02 0 0 0 100 0.5 0.64 Blank Footnotes: ] 04 GS20 1/31/02 0 0 0 100 0.5 0.64 Blank Footnotes: 1 Reporting Notes: (1) Fibers/cc cannot .calculated samples (or blanks) with no air volume. Analyzed by: Devin Ahyee ; Date Analyzed: 1/31/02 Samples analyzed by NIOSH 7400(A) Method, Issiiue#2, 8/15/94: Limit of Detection= 5.5 fibers per 100 fields or 7 fibers/mm2: This report relates ONLY Io the sample analysis expressed as fibers/sq mm of filter area: ND=No fibers observed: NA=Not Analyzed; Walton-Beckett graticlc field area = 0.00785 mm2; 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, AIHA # 102843.

NYC-WTC_000174401