NYC-WTC_000208373

NYC 9/11 Public Portal Document

Summary ofAsbestos Sampling Results Page 2 of 3 Address: J 30 Water Street Date sampled: November 30, 200J

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Sample Numbers A-0-24 A-C-24 A-Rl-24 A-R2-24 A-R2-24*

Concentration of Fibers in 0.002 0.001 0.001 0.005 0.005* HAir at 130 Water Street (fee)** Concentration of Fibers (fZee) in comparison locations <0.001 toO.OOl <0.001 to 0.002 <0.001 to 0.003 <0.001 to 0.003 <0.001 to 0.003 NYC Re-occupancy 0.01 0.01 0.01 0.01 0.01 Standard (f/cc)*** ♦ Denotes a second air sample taken in the same location for quality control purposes. ** f/cc is fibers in each cubic centimeter (cc) of air. Thi s is calculated from the number of fibers seen on the air filter and the volume of air pulled through the filter measured in cubic centimeters of air. ♦** New York City Department of Environmental Protection asbestos clearance criteria for post-abatement work (Rules of the City of New York, Title 15, Chapter 1)

Asbestos in air as determined by Transmission Electron Microscopy (TEM) analysis: TEM analysis is very specific and can distinguish between asbestos and non-asbestos fibers, such as textiles. This analysis determines if the fibers seen in the PCM analysis are asbestos, or if they are some other material. TEM analysis was conducted on all air samples that showed more than 0.003 f/cc in the air by PCM analysis. No asbestos fibers were found in the TEM analysis of these air samples,2

Results of Transmission Electron Microscopy (TEM) testing of air at 130 Water St, Nov 30, 2001 Area Sampled Residence 2 Residence 2

Sample Numbers A-R2-24 A-R2-24* Concentration of Asbestos Fibers in Air at 130 Water <0.001 <0.001 Street (fZcc)**_______________________________ Concentration of All Fibers (f/cc) in comparison <0.001 to 0.003 <0.001 to 0.003 locations___________________________________ NYC Re-occupancy Standard (f/cc)*** 0.01 0.01 * Denotes a second air sample taken in the same location. ** f/cc is fibers in each cubic centimeter (cc) of air. This is calculated from the number of fibers seen on the air filter and the volume of air pulled through the filler measured in cubic centimeters. *** New York City Department of Environmental Protection asbestos clearance criteria for post-abatement work (Rules of the City of New York, Title 15, Chapter 1)

2 The TEM method employed here, NIOSH 7402, counts fibers of the same size as those detected by PCM analysis. Fibers reported here are greater than or equal to 5 microns in length and 0.25 microns in width.

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NYC-WTC_000208374