NYC-WTC_000197534

NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan October 24, 2001 Indoor Air Quality Assessment Page 2 Stuwesant Hiah School fM477) ATC Project No. 15-19125-0246

The assessment was performed consistent with generally accepted indoor air quality assessment practices. As with all such assessments, there were inherent limitations created by constraints of time, operational and work practice variability, variations in air contaminant concentrations, and sampling and analytical accuracy. The results of the sampling represent conditions found on the dates of the survey and may not represent conditions found at other times. The information presented in this report should be used by the Board of Education as a guide to assess the need for further improvements in current indoor air quality control activities.

EVALUATION CRITERIA

Currently, there are no regulatory standards for indoor air quality in non-industrial buildings, such as offices and schools. For the real-time data collected, ATC uses the commonly accepted guidelines cited in the following publications:

Ventilation for Acceptable Indoor Air Quality (ASHRA£ 62-1999), American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE); Thermal Environmental Conditions for Human Occupancy (ASHEAE 66-1992); Industrial Hygienists Guide to Indoor Air Quality Investigations (1993), American Industrial Hygiene Association (AIHA).

Table 1 lists target guidelines for the parameters that ATC evaluated during this investigation. Meeting one, some, or all of the listed values does not assure that acceptable indoor air quality will be achieved at all times.

TABLE 1 TARGET GUIDELINES FOR INDOOR AIR QUALITY PARAMETERS EVALUATED

TARGELLEVEL ", ' Carbon Dioxide <700 parts per million (ppm) ASHRAE 62 JCOty___________ above background level Carbon Monoxide 9 ppm USEPA NPAAQS (as cited in (CO) ASHRAE 62) Respirable 65 micrograms per cubic meter USEPA NPAAQS Particulates (PM2.5) of air (pg/m^) 24-hour average Temperature Summer: 73-79°F at 50% RH ASHRAE55 Winter: 69-76°F at 50% RH Relative Humidity 30 - 60 % ASHRAE55 Total Volatile 1 ppm Organic Compounds AIHA (TVOC) USEPA = United States Environmental Protection Agency NPAAQS = National Primary Ambient-Air Quality Standard AIHA = American Industrial Hygiene Association

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