NYC-WTC_000208008

NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan May 10, 2002 Respirable Particulate Monitoring Page 2 Various LxjcationsZ Manhattan ATC Project No. 15-19125-0314

TARGET GUIDELINES FOR AIR QUALITY PARAMETERS EVALUATED*

Respirable 65 micrograms per cubic Particulates meter of air (pg/m^) 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 5:45 A.M. to 3:58 P.M. The lAQ field report forms are provided as the Attachment.

The outdoor PM2.5 concentrations ranged from 12 pg/m^ to 25 pg/m^ with an average of 20 pg/m^. The indoor concentrations ranged from 9 pg/m^ to 22 pg/m3 with an average of 16 pg/m^. None of the indoor or 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 or above the USEPA recommended guideline for children and sensitive individuals of 40 Pg/m3.

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

CONCLUSION Based on our measurements, none of the indoor or outdoor readings were above the NPAAQS of 65 jxg/m^ 24-hour average concentration of particulate matter 2.5 micrometers or less in aerodynamic diameter or above the USEPA recommended guideline for children and sensitive individuals of 40 pg/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, ATC ASSOCIATES INC. Reviewed by:

/ Giannis Efstatmou James R. Cohn, CIH, CSP lZ Senior Project Manager Regional Manager, Industrial Hygiene Division

Attachment

CITY_21MC100_003018049

NYC-WTC_000208009