NYC-WTC_000213077

NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan May 21,2002 Indoor Air Quality Measurements Page 4 Stuvvesant High School (M477) ATC Project No. 15-19125-0246

In addition to higher efficiency rating filters on their HVAC units, portable High Efficiency Particulate Air (HEPA) purifiers were placed in Rooms 327, 333, 638 and 740. The PMp s concentration range for these rooms was 12-18 pg/m^ with an average of approximately 16 pg/m3.

* The measurements made during this assessment were instantaneous readings, the NP.AA.QS is a 24-hour average.

T^OC Concentration

TVOCs inside the building were 0.0 ppm for all readings. The'outdoor TVOC concentrations were also 0.0 ppm.

OBSERVATIONS

During this assessment, ATC noted the following: • The interior of the building appeared clean and free of dust and debris; • The building was occupied at the time of the assessment; • No smoke odor was detected in the building;

FINDINGS

Based on the real-time measurements, the following findings are presented:

1. Concentrations of indoor respirable particulates, CO , and TVOCs were below applicable standards and guidelines. 2. Twenty-three (23) measurements of relative humidity were below the ASHRAE recommended range of 30 to 60 percent for occupant comfort. 3. One hundred and sixteen (116) indoor temperature measurements were below the range of 73 to 79°F (at 50 percent relative humidity) recommended by ASHRAE Standard 55-1992 during the mechanical cooling season (summertime conditions). 4. Eleven (11) of the CO2 measurements were above the ASHRAE Sundard 62-1999 recommended maximum concentration of <700 ppm above the background level. 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 CO2 indoors is occupant respiration.

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