Indoor Air Quality Report, March 21, 2002, NYC School

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I Mr. Bernard P. Orlan March 22, 2002 Indoor Air Quality Assessment Page 3 H.S. of Economics and Finance (M833)________ ATC Project No. 15-19125-0291 Real-Time Environmental Measurements

ATC collected one hundred (100) sets of real-time environmental measurements consisting of eighty-eight (88) in the school building and twelve (12) outdoors. Field data sheets are found m the Attachment. Readings began at 8:03 A.M. and concluded after 2:51 P.M. The results are described below.

Temperature

Indoor dry bulb temperature measurements ranged from 64.8 °F to 75 °F. Fourteen (14) of the indoor measurements for temperature were below and seventy-four (74) were within the range of 68 to 75°F (at 50 percent relative humidity) recommended by ASHRAF Standard 55-1992 during the heating season (wintertime conditions). The outdoor temperature ranged from 46.5 to 63.1 °F.

Relative Humidity

The relative humidity indoors ranged from 26.7 percent to 41.9 percent. Forty-eight (48) of the indoor measurements for relative humidity are below and forty (40) were within the ASHRAF recommended range of 30 to 60 percent for occupant comfort. The outdoor relative humidity ranged from 26.1 to 33.4 percent.

Carbon Dioxide Concentration

Carbon dioxide concentrations indoors ranged from 339 ppm to 1442 ppm. Three (3) of the indoor measurements for CO2 were above the ASHRAF Standard 62-1999 recommended maximum concentration of <700 ppm above the background level. The outdoor (background) CO2 concentration was 465 ppm. Therefore, the maximum acceptable level of CO2 at this location was 1165 ppm (background level + 700 ppm). The highest reading (1442 ppm) was measured in the cafeteria at approximately at 1:29 PM with 160 occupants. Fevels 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 between 1 to 3 ppm. These concentrations were below the NPAAQS/ASHRAF guideline of 9 ppm. The outdoor CO concentration ranged from 2 to 5 ppm.

Respirable Particulates (PMjj)

Respirable particulate concentrations* indoors ranged between 4 pg/m^ to 53 pg/m^ with a:n average 12 pg/m^. All of the indoor measurements were below the NPAAQS of 65 pg/m^ 24- hour average concentration of particulate matter 2.5 micrometers or less in aerodynamic diameter. One (1) of the eighty-eight (88) instantaneous indoor readings was above the USEPA recommended concentration of 40 pg/m^ for sensitive individuals and children. The outdoor respirable particulate concentration ranged from 37 pg/m^ to 74 pg/m^ with an average of 64 pg/m^. Seven (7) of the outdoor measurements were above the NPAAQS of 65 pg/m^ 24-hour average concentration of particulate matter 2.5 micrometers or less in aerodynamic diameter.

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