NYC-WTC_000202416

NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan November 5, 2002 Respirable Particulate Sampling Page 2 P.S. 150M ■ ATC Project No. 15-19125-0289

Table 1 lists target guideline for the parameter that ATC evaluated during this investigation. Meeting the listed value does not assure that'acceptable indoor air quality will be achieved at all times.

■TABLE 1 ■ 3 3 TARGET GUIDELINES FOR INDOOR AIR QUALITY PARAMETER 3' \ i devaluated'(3^ 3 3'3/1 r 31 Ml. WEsn-<« org.amzation Respirable 65 3micrograms per cubic USEPA NPAAQS Particulates (PM2.5) meter of air (pg/m^) 24-hour average Respirable - ' r 40 pg/rh^ , 24-hour average USEPA - Recommendation for Particulates (PM2.5) children/sensitive individuals USEPA - United States Environmental Protection Agency - NPAAQS = National Primary Ambient-Air Quality Standard

RESULT ri

ATG collected one (1) 24-hour PM, 5 sample in the school’s .Mairi Lobby.

The 24-hQur average concentration of PM2.5 was less than 3.47 ug/m^ (less than the limit of detection) which is below both the EPA NPAAQS foT PMj 5 of 65 ug/m^ arid the EPA recommended level of 40 ug/md '

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

Sincerely, ATC ASSOCIATES INC. 3

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

Attachment

CITY_21MC100_003272535

NYC-WTC_000202417