Indoor Air Quality Report, May 9, 2002, NYC School

NYC 9/11 Public Portal Document

Mr. Bernard P Orlan May 10, 2002 Indoor Air Quality Assessment Page 3 H.S. (TJ^c^noimcs^ndJFinanc^(M833)________ ATC Project No. 15-19125-0291 Real-Time Environmental Measurements

ATC collected one hundred (100) sets of real-time environmental measurements consisting of eightj-eight (88) inside the school building and twelve (12) outdoors. Field data sheets are found in the Attachment. Readings were collected between morning to evening. The results are descnbed below.

Tempi’rature

Indoo- dry bulb temperature measurements ranged from 62.3 °F to 79.1 °F. Six (6) of the indoor measurements collected were bellow and three (3) measurements were bellow and seveny nine (79) were within the range of 73 to 79°F (at 50 percent relative humidity) recommended by ASHRAE Standard 55-1992 during the summer season. The outdoor temperature measurements ranged from 57.1 °F to 63.3 °F.

Relative Humiiiity

The relative humidity indoors ranged from 32.9 percent to 54.3 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 36.2 to 46.7 percent.

Carbon Dioxide Concentration

Carbo l dioxide concentrations indoors ranged from 528 ppm to 1340 ppm. Two (2) of the indoor measurements for CO2 were above the ASHRAE Standard 62-1999 recommended maximum concentration of <700 ppm above the background level. The outdoor (background) CO2 concentration ivas 459 ppm. Therefore, the maximum acceptable level of CO2 at this location was 1 59 ppm (background level + 700 ppm). The highest reading (1340 ppm) was measured in stairwell A to 6^^ floor around 11.27 AM. The stairwell was fully occupied at that time. Levels above the recommended maximum do not indicate a health risk. Carbon dioxide measurements are us ed as an indicator of available outdoor air. The primary source of CO2 indoors is occupant respiration.

Carbon Monoxide Concentration

Carbon mono?!ide concentrations indoors ranged from 0 to 1 ppm. These concentrations were below the NPAAQS/ASHRAE guideline of 9 ppm. The outdoor CO concentrations ranged from 1 to 3 ppm.

Respirable Particulates (PM2 5)

Respirable particulate concentrations* indoors ranged between 1 pg/m^ to 47 pg/mJ with an average of 9 pg/m^- All of the indoor measurements for respirable particulates were below the NPA/.QS of 65 pg/m^ 24-hour average concentration of particulate matter 2.5 micrometers or less ir. aerodynamic diameter and one (1) measurement was above the USEPA recommended concentration of 40 pg/m^ for sensitive individuals and children. The respirable concentrations outdoors ranged between 19 pg/m^ to 31 pg/m^ with an average of 25 pg/m^-

CONFIDENTIAL, CITY_21MC100_003462524 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008

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