Indoor air quality report letter, P.S. 150M, May 2002

NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan May 17, 2002 Indoor Air Quality Assessment Page 4 P. S. 150M ATC Project No. 15-19125-0289 respirable particulate concentration measurements ranged from 16 to 22 pg/m^ with an average of 19 pg/m3.

* The measurements made during this assessment were instantaneous readings, the NPAAQS is a 24-hour average.

TVOC Concentrations

TVOCs were not detected anywhere inside the building (0.0 ppm). The outdoor TVOC concentration was also 0.0 ppm.

OBSERVATIONS

During this assessment, ATC noted the following: • There was construction work going on in the plaza; • The school building was occupied at the time of the assessment; • No smoke odor was detected in the building;

FINDINGS

Based on the real-time measurements, the following findings are presented:

1. Concentrations of respirable particulate, CO, and TVOCs were within applicable standards and guidelines; 2. All measurements of relative humidity were within the ASHRAE recommended range of 30 to 60 percent for occupant comfort. 3. Two (2) of the measurements were below the range of 73 to 79°F (at 50 percent relative humidity) as recommended by the ASHRAE Standard 55-1992 during the mechanical cooling season (summertime conditions). 4. One (1) of the CO2 measurements was above the ASHRAE Standard 62-1999 recommended maximum concentration of <700 ppm above the background level. The highest reading (1130 ppm) was taken by the slop sink area in the hallway at 1:00 PM. Levels above the recommended maximum do not indicate a health risk. Carbon dioxide measurements are used as an indicator of available outside makeup air. The primary source of CO2 indoors is occupant respiration. The school building was occupied during ATC’s assessment.

It is our pleasure to provide these indoor air quality services to the New York City Board of Education. If you have any questions about this report, please call (212) 353-8280, extension 211 or 212.

Sincerely, Reviewed by: A TC ASSOCIA TES INC. '\

Tvnel Javy James R. Cohn, CIH, CSP Senior I’rOie/t Manager Regional Manager Industrial Hygiene Division Attachment

CONFIDENTIAL, CITY_21MC100_005759769 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008

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