NYC-WTC_000208064

NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan December 19, 2001 Real-Time Air Monitoring Page 5 P.S. 89 (Manhattan) ATC Project No. 15-19125-0297

The 24-hour average indoor PM2,5 concentration (converted to micrograms per cubic meter) was 20 ug/m3. The average outdoor concentration, as measured on the roof, was 15 ug mA Both values are below the NPAAQS for PM2.5 of 65 ug/m^ (24-hour average). Copies of the test summaries and graphs that were downloaded at the end of each sampling session are provided as Attachment 2.

FINDINGS

Based on the visual inspection of the occupied spaces and real-time measurements, the following findings are presented:

1. Measurements of concentrations of CO, TVOCs and respirable particulates were below recommended maximums.

2. Temperature and relative humidity measurements and CO2 concentrations were below the ASHRAE-recommended ranges, however the building was unoccupied.

3. H2S, NO and SO2 were not detected.

4. NO2 was detected at similar levels indoors and outdoors.

CONCLUSION

Based on our observations and measurements of the specified parameters, ATC concludes that the indoor air quality at the assessed location was acceptable at the time of ATC’s investigation.

It is our pleasure to provide these indoor air consultative services to the New York City Board of Education. If you have any questions about this report, please contact me at (212) 353-8280, extension 212

Sincerely, A TC ASSOCIA TES INC.

James R. Cohn, CIH, CSP Regional Manager Industrial Hygiene Division

Attachments

CITY_21MC100_003018940

NYC-WTC_000208068