NYC-WTC_000199886

NYC 9/11 Public Portal Document

Instrument readings for total volatile organic compounds, nitrous oxide, sulfur dioxide, and hydrogen sulfide were all below the instrument detection limit. Nitrogen dioxide was measured at average concentrations ranging from 0.1 ppm to 0.3 ppm indoors, and 0.2 ppm to 0.4 ppm outdoors. These levels exceed the USEPA ambient air quality standard of 0.053 ppm. These readings are believed to be the result of instrument enor. Re-testing using a more sensitive meter at a nearby school confirmed instrument error from the earlier readings at that school and re-testing of nitrogen dioxide levels at PS 234 have confirmed this conclusion, based on information received verbally from ATC.

Wipe Samples

Dust Sampling for Asbestos (December 5,2001)

A total of 22 dust samples were collected from throughout the school on December 5 for analysis of asbestos. ATC reported that no asbestos was detected in any of the 22 dust samples.

Comprehensive Surface Sampling (December 5,2001)

Ten wipe samples were collected from various locations inside PS 234 on December 6, 2001 for a variety of potential contaminants, including dioxins and dibenzofurans, metals, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs). The sample locations included;

• Cafeteria - windowsill • Kitchen - serving windowsill • Room 116 - table surface • Room 120-windowsill • Room 211 - table surface • Library - table surface L iLrci. Lookcase surface • Room 305 - bookcase surface • Room 316 - table surface • Gymnasium - landing.

The results of the analyses of these samples are discussed below.

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CITY_21MC100_008972444

NYC-WTC_000199893