NYC-WTC_000232862

NYC 9/11 Public Portal Document

Summary of Asbestos Sampling Results Page 2 of 2

Address: Building 2O's address Date sampled: Nov 27, 2001

Airsamples

Airborne fibers as determined by Phased Contrast Microscopy (PCM): An air sample is collected by pulling air through a filter. The filter catches fibers an is sent to a laboratory to determine what types of fibers were in the air. Phase contrast microscopy identifies fibers based on size and shape, but not mineral composition. Therefore, the fibers seen by PCM include asbestos fibers as well as other fibers, such as textiles, fiberglass, cellulose, which might be present in your home. By counting all fibers, we are being more protective of your health when we compare this to our screening value for asbestos fibers.

Area Sampled Outside Common Residence 1 Residence 2 Sample Numbers A-O-20 A-C-20 A-Rl-20 A-R2-20 A-O-X-20* Concentration of Fibers in Air <001 <001 <001 <001 at this location_____________ <001* Concentration of Fibers in Air <.001 to .001 <•001 to .002 <•001 to .002 <.001 to .002 at background locations Screening Value .01 f/cc .01 f/cc .01 f/cc .01 f/cc

*Denotes co-located, 2“** sample

CITY_21MC100_003153410

NYC-WTC_000232865