NYC-WTC_000229818

NYC 9/11 Public Portal Document

104 East 25th Street I New York, New York 10010 www.atc-enviro.com 212.353.8280 Fax 212.353.8306

December 7, 2001

3 Mr. Bernard P. Orlan Director, Environmental Health & Safety New York City Board of Education 28-11 Queens Plaza North Long Island City, NY 11101-4008

Re: Indoor Air Quality Assessment PubUc School 234M 292 Greenwich Street New York, New York ATC Project No. 15-19125-0279

Dear Mr. Orlan:

ATC Associates Inc. (ATC) is pleased to provide this report of indoor air quality (lAQ) assessments conducted on November 29 - December 1, 2001, at the referenced school. Tlie New York City Board of Education (BOE) requested this assessment to determine indoor air quality prior to reopening the school.

SCOPE OF WORK

ATC conducted this evaluation to assess the basic parameters of temperatoe, relative humidity, carbon dioxide (COj) and carbon monoxide (CO). -

Total volatile organic compounds (TVOCs) and respirable particulates (PM2.5) were also measured.

Tenzin Namgyal and Wagdi.Abdelshahid, Industrial Hygienists, of ATC’s New York City office, conducted the assessment. ATC’s findings and conclusions are based on a visual inspection, real-time environmental measurements and conditions present in the school at the time, of the assessment.

ATC measured temperature, relative humidity, CO2 and CO with a Q-Trak® Model 8551, manufactured by TSI, Inc.

ATC measured concentrations of respirable particulates with a Dust-Trak® Aerosol Monitor Model 8520, manufactured by TSI, Inc.

ATC measured concentrations of TVOCs using a RAE Systems, Inc. MiniRAE® photoionization detector (PID).

The assessment was performed consistent with generally accepted indoor air quality assessment practices. As with all such assessments, there were inherent limitations created by constraints of

CONFIDENTIAL, CITY_2IMCl00_001897988 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008 NYC-WTC_000229818