PCM fiber results, 100 Church Street, Jan 2002

NYC 9/11 Public Portal Document SciLAb#: 202013653 ra 01 1

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

01 GS-1 1/30/02 3 300 900 100 2 2.55 <0.003 Ceasar Rodriguez 02 GS-2 1/30/02 3 300 900 100 6 7.64 0.003 Mario Davis's sample 03 GS-3 1/30/02 3 300 900 100 3 3.82 < 0.003 Ceasar Rodriguez 04 GS-4 1/30/02 3 300 900 100 8 10.19 0.004 Mario Davis's Sample 05 GS-5 1/30/02 0 0 0 100 0.5 0.64 Blank Footnotes; 1 06 GS-6 1/30/02 0 0 0 100 0.5 0.64 Blank Footnotes: 1 Reporting Notes: (1) Fibers/cc cannot Iculated for^amples (or blanks) with no air volume. Analyzed by; Devin Ahyee ; Date Analyzed; 1/31/02 Samples analyzed by NIOSH 7400(A) Method, Issue »2, 8/15/94; Limit of Detection= 5.5 fibers per 100 fields or 7 fibers/mraZ; 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 graticle 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 compliante 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.

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