Indoor Air Quality Report, March 14, 2002, NYC School

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Mr. Bernard P. Orlan March 15, 2002 Indoor Air Quality Assessment Page 3 H.S. of Economics and Finance (M833) ATCProiectNpM5d9125r0291 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 in the Attachment. Readings began at 10:43 A.M. and concluded after 5:57 P.M. The results are described below.

Temperature

Indoor dry bulb temperature measurements ranged from 68.5 °F to 79.6 °F. Forty-seven (47) of the indoor measurements for temperature were above and forty-one (41) were within the range of 68 to 75°F (at 50 percent relative humidity) recommended by ASHRAE Standard 55-1992 during the heating season (wintertime conditions). The outdoor temperature ranged from 60.8 to 63.7 °F.

Relative Humidity

The relative humidity indoors ranged from 30.9 percent to 48.1 percent. All of the indoor measurements for relative humidity were within the ASHRAE-recommended range of 30 to 60 percent for occupant comfort. The outdoor relative humidity ranged from 30.9 to 35.6 percent.

Carbon Dioxide Concentration

Carbon dioxide concentrations indoors ranged from 433 ppm to 1476 ppm. Three (3) of the indoor measurements for CO2 was above the ASHRAE Standard 62-1999 recommended maximum concentration of <700 ppm above the background level. The outdoor (background) CO2 concentration was 502 ppm. Therefore, the maximum acceptable level of CO2 at this location was 1202 ppm (background level + 700 ppm). The highest reading (1482 ppm) was measured in Room #510 approximately at 11:31 AM with 15 occupants. Levels above the recommended maximum do not indicate a health nsk. 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/ASHRAE guideline of 9 ppm. The outdoor CO concentration ranged from 3 to 4 ppm.

Respirable Particulates (PM2,5)

Respirable particulate concentrations* indoors ranged between 10 pg/m^ to 47 pg/m3 with an average 19 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. Two (2) of the eight-eight (88) instantaneous indoor readings were above the USEPA recommended concentration of 40 pg/m^ for sensitive individuals / children. The outdoor respirable particulate concentration ranged from 52 pg/m^ to 124 pg/m^ with an average of 87 pg/m-\ Two (2) of the outdoor measurements were above the NPAAQS of 65 pg/m^ 24-hou’' average concentration of particulate matter 2.5 micrometers or less in aerodynamic diameter. All

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