NYC-WTC_000199242

NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan May 24, 2002 Respirable Particulate Monitoring Page 2 Various Locations/Manhattan ATC Project No. 15-19125-0314 TARGET GUIDELINES FOR AIR QUALITY PARAMETERS EVALUATED* PARAMETER TARGET LEVEL___________ AGENCY Respirable 65 micrograms per cubic Particulates meter of air (fxg/m3) 24 hour USEPA NPAAQS (PM2.5) average Respirable USEPA recommendation Particulates 40 p.g/m3 24 hour average for children/sensitive (PM2.5) individuals USEPA = United States Environmental Protection Agency NPAAQS = National Primary Ambient-Air Quality Standard

REAL-TIME SAMPLING RESULTS

Thirty-one (31) indoor and thirty-four (34) outdoor respirable particulates measurements* were collected from twenty-nine (29) school locations in Manhattan, ranging from West 11-^ Street to East 33"' Street. The measurements were made from 5;53 A.M. to 4;24 P.M. The lAQ field report forms are provided as the Attachment.

The outdoor PM2.5 concentrations ranged from 37 ^xg/m^ to 94 ng/m^ with an average of 69 (xg/m^. The indoor concentrations ranged from 12 (xg/m^ to 71 fxg/m3 with an average of 48 pg/m^. One (1) of the indoor and twenty-four (24) of the outdoor readings were above the NPAAQS of 65 (xg/m^ 24-hour average concentration of particulate matter 2.5 micrometers or less in aerodynamic diameter. Twenty-three (23) of the indoor and thirty-three (33) of the outdoor readings were above the USEPA recommended guideline for children and sensitive individuals of 40 pg/m’.

These measurements were instantaneous readings, the NPAAQS and the recommendation for children are 24-hour averages.

CONCLUSION Based on our measurements, one (1) of the indoor and twenty-four (24) of the outdoor readings were above the NPAAQS of 65 pg/m^ 24-hour average concentration of particulate matter 2.5 micrometers or less in aerodynamic diameter. Twenty-three (23) of the indoor and thirty-three (33) of the outdoor readings were above the USEPA recommended guideline for children and sensitive individuals of 40 ug/m^.

It is our pleasure to provide these air quality consultative services to the New York City Board of Education. If you have any questions about this report, please call (212) 353-8280, extension 212 or 211.

Sincerely, AT^J^SSOCLATES INC.

Arrtel Javalj V ohn, CIH, CSP Senior Prpjject Manager Regional Manager, Industrial Hygiene Division

Attachment

CITY_21MC100_006740067

NYC-WTC_000199243