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NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan October 26, 2001 Indoor Air Quality Assessment Page 3 Stuyvesant Hish School (M477) ATC Project No. 15-19125-0246

Real-Time Environmental Measurements

ATC collected one hundred and one (101) sets of real-time environmental measurements consisting of ninety (99) in the school building and two (2) outdoors. All ten floors of the school were surveyed. These results are described below. Field data sheets are found in Attachment 1. Readings began at 10:15 A.M. and concluded after 2:40 P.M.

Temperature

Indoor dry bulb temperature measurements ranged from 69.2 °F to 78.4 °F. Five (5) measurements were above the range of 69 to 76°F (at 50 percent relative humidity) recommended by ASHRAE Standard 55-1992 during the heating season (wintertime conditions). These measurements were collected from the 3’'d, 6^^ and floors. The outdoor temperature range was 73.4 to 75.5 °F.

Relative Humidity

The relative humidity indoors ranged from 31.0 percent to 60.4 percent. One measurement was above the ASHRAE-recommended range of 30 to 60 percent for occupant comfort. The outdoor relative humidity range was 17.2 to 50.4percent.

Carbon Dioxide Concentration

Carbon dioxide concentrations indoors ranged from 420 ppm to 1548 ppm. Twelve (12) COg measurements were above the ASHRAE Standard 62-1999 recommended maximum concentration of <700 ppm above the background level. The outdoor (background) CO2 concentration range was 370 ppm. Therefore, the maximum acceptable level of CO2 at this location was 1070 ppm (background level -h 700 ppm). The highest reading, 1548 ppm, was in Room 303. Rooms with CO2 levels above the recommended maximum were found on all floors except the 2nd and 6th floors. Levels above the recommended maximum do not indicate a health risk. Carbon dioxide measurements are used as an indicator of available outdoor air. The primary source of CO2 indoors is occupant respiration.

Carbon Monoxide Concentration

Carbon monoxide concentrations indoors were 0 ppm for all readings. These concentrations were below the NPAAQS/ASHRAE guideline of 9 ppm. The outdoor CO concentration was 0 ppm.

Respirable Particulates (PM2_5)

Respirable particulate concentrations indoors ranged between 11 pg/m3 and 52 pg/m^. None of the measurements were above the NPAAQS of 65 pg/m^ 24-hour average concentration of particulate matter 2.5 micrometers or less in aerodynamic diameter. The outdoor respirable particulate concentration range was 17 to 54 pg/m^.

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