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NYC 9/11 Public Portal Document

WSA Management JLC Project # 01-2214 November 16, 2001 Procedure page 2 Air Sampling Analysis and Introduction of r defined as the process of measuring t filter content of a known volume by Air sampling is referenced filter membrane over a specified period of time Each sample is cross entrained on a internal code to ensure field designation and a JLC lab nHEPA filter clean bench to avoid any possible of custody. Sample preparation takes place within contamination.

Methodology Institute of Occupational Safety and Test procedures for these samples conform to the National Health (NIOSH) standards. of ersons level approximating esreathing zone Air sampling was conducted at a erations. Samp collected shoufdpepresent theartea'so be present in the area during normal op typical airborne fiber concentration. cellulose ester were collected on fully exposed 25 millimeter, 0.8 micrometer (pm) All samples conductive cowl. membrane air sampling cassettes with

Analytical Procedures ved laced on approximating twenty-five ent of the total 'lter was A section of the filter andetone ac exposedrto apProxirnately 250 microliter (p) of laced a pre-cleaned microscope slide and then was and a clean 1.5 was triacetin vapor. A single 3.0 - 3.5 NI drop of heated on slide heate#until claetyslalplowedp theneated analysis to upon the filter. The prepared slide was be conducted. NIOSH 7400 accomplished utilizing a Phase Contrast Microscope in accordance with Analysis was method, counting rule A.

Phase Contrast Microscopy scope, uses an Olympus H-PC Phase Contrast solving the filter )

JLC Environmental's laboratory were analyzed by equipped with a Walton-Beckett Graticule. p PCM at 400x les

above) and then counting the fibers with through a chemical process (described light contrast een the object the background, magnification. Phase contrast increases the Normally, 100 m coscopic fields or 00 the microscopists ability to se thus enhancing first. fibers are counted, whichever occurs

Analytical Results The Analytical Results" represents the slts of the analysis of the air.es. The "Summary of If final tests 0.01 fbe /cubic centimeter (f/cc) of PCM limit of reliable quantification is less than site must be re-cleaned and re-tested. the entire work do not meet these requirements,

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