Indoor Air Quality Report, May 10, 2002, NYC School

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Mr. Lernard P. Orlan May 13, 2002 Indoc r Air Quality Assessment Page 3 H.S. of Economics and Finance (M833)___________________ ATC Project No. 15-19125-0291 in the Attachment. Readings were collected between morning to evening. The results are descr bed below.

Tempsraliire

IndocT dry bulb temperature measurements ranged from 71.6 °F to 79.8 °F. Thirteen (13) of the indoor measurements collected were below and two (2) measurements were above the range of 73 to 79 T (at 50 percent relative humidity) recommended by ASHRAE Standard 55-1992 during the summer season. The outdoor temperature measurements ranged from 68.6 °F to 80.3 °F.

Relative Humidity

The relative humidity indoors ranged from 46.1 percent to 64.6 percent. One (1) of the indoor measurements for relative humidity was above the ASHRAE recommended range of 30 to 60 percent for occupant comfort. The outdoor relative humidity ranged from 28.1 to 57.4 percent.

Carbon dioxide concentrations indoors ranged from 421 ppm to 1260 ppm. All of the indoor measurements for CO, were within the ASHRAE Standard 62-1999 recommended maximum conceitration of <700 ppm above the background level. The outdoor (background) COj concentration was 481 ppm. Therefore, the maximum acceptable level of CO, at this location was 1181 ppm (background level + 700 ppm). 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 COj indoors is occupant respiration.

Carbon Monoxide Concentration

Carbon monoxide concentrations indoors were 1 ppm for all readings. These concentrations were below the NPAAQS/ASHRAE guideline of 9 ppm. The outdoor CO concentrations were also 1 ppm for all collected readings.

Respirable Particulates (PMj s)

Respirable particulate concentrations* indoors ranged between 9 pg/m’ to 49 pg/m’ with an average of 17 ug/m’- All of the indoor measurements for respirable particulates were below the NPA?iQS of 65 pg/m’ 24-hour average concentration of particulate matter 2.5 micrometers or less in aerodynamic diameter. One (1) indoor measurement was above the USEPA recommended concentration of 40 pg/m’ for sensitive individuals and children. The respirable concentrations outdoors ranged between 16 pg/m’to 98 pg/m’ with an average of 40 pg/m’

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