Indoor Air Quality Report, P.S. 150M, Apr 2002

NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan April 17, 2002 Indoor Air Quality Assessment Page 3 P. S. 150M ATC Project No. 15-19125-0289 r Real-Time Environmental Measurements

ATC collected forty (40) sets of real-time environmental measurements consisting of thirty (30) from inside the school building and ten (10) from outdoors. All three floors of the school building were surveyed. These results are described below.

Field data sheets are found in Attachment 1. Readings began at 9:00 A.M. and concluded at approximately 10:30 A.M.

Temperature

Indoor diy bulb temperature measurements ranged from 71.8°F to 75.8°F. Ten (10) of the measurements were above the range of 68 to 75°F (at 50 percent relative humidity) as recommended by the ASHRAE Standard 55-1992 during the heating season (wintertime conditions). The outdoor temperature measurements ranged from 74.5°F to 77.0°F.

Relative Humidity

The relative humidity indoors ranged from 41.7 to 53.7 percent. All of the measurements were within the ASHRAE-recommended range of 30 to 60 percent for occupant comfort. The outdoor relative humidity measurements ranged from 46.4 to 51.6 percent.

CarbonDigjddeConcentrqtipn

Carbon dioxide concentrations indoors ranged from 543 ppm to 1219 ppm. All of the CO2 measurements were within the ASHRAE Standard 62-1999 recommended maximum concentration of <700 ppm above the background level. The maximum outdoor (background) CO2 concentration was 547 ppm. Therefore, the maximum acceptable level of CO2 at this location was 1247 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 outside makeup air. The primary source of CO2 indoors is occupant respiration. The school building was occupied during ATC’s assessment.

CarbonMonoxide Concentration

Carbon monoxide indoor concentrations ranged from 3 ppm to 4 ppm. These concentrations were below the NPAAQS/ASHRAE guideline of 9 ppm. The outdoor CO concentration was 4 ppm for all collected readings.

Respirable Particulates (PM2_5) ppm.

Respirable particulate concentrations* indoors ranged between 37 pg/m^ to 86 pg/m^. Eighteen (18) of the indoor measurements were above the NPAAQS of 65 pg/m and twenty-eight (28) indoor measurements were above the USEPA recommendation of 40 pg/m^ for sensitive individuals and children. The average PM2.5 concentration for the entire school building was approximately 67 pg/m^. The PM2.5 average concentration was above the USEPA recommended concentration of 40 pg/m^ for sensitive individuals and children. The outdoor

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