NYC-WTC_000214366

NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan April 19, 2002 Indoor Air Quality Assessment Page 4 P. S. 150M ATC Project No. 15-19125-0289 The outdoor respirable particulate concentration measurements ranged from 28 to 34 pg/m^ with an average of 31 pg/m^.

* 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;

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

1. Concentrations of CO, CO2 and TVOCs were below applicable standards and guidelines. 2. Four (4) of the indoor measurements for temperature were below and twenty-six (26) measurements were within the range of 73 to 79 °F (at 50 percent relative humidity) as recommended by the ASHRAE Standard 55-1992 during the summer conditions. 3. All of the measurements for relative humidity were within the ASHRAE-recommended range of 30 to 60 percent for occupant comfort. 4. All of the indoor and outdoor measurements for PM2.5 were below the NPAAQS of 65 pg/m^ for 24-hour average concentration of particulate matter 2.5 micrometers or less in aerodynamic diameter and the USEPA recommendation of 40 pg/m^ for sensitive individuals and children.

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 TCASSOCIA TES INC.

Amel Javal^ James R. Cohn, CIH, CSP Senior Project Manager Regional Manager Industrial Hygiene Division Attachment

CITY_21MC100_002870407

NYC-WTC_000214369