WTC health criteria appendix, Dec 2001

NYC 9/11 Public Portal Document

Contaminant Site Worker Resident ® Ethylbenzene 100 ppm 2.5 ppm Freon 22 1,000 ppm^'"** 140 ppm

Propylene LEL simple asphyxiant Styrene 100 ppm 2.3 ppm

alpha methylstyrene 100 ppm .1 ppm ® Tetrahydrofuran 200 ppm .9 ppm Toluene 200 ppm 1.1 ppm Xylenes 100 ppm 1 ppm Reactive Gases Acetaldehyde 200 ppm .05 ppm 1.3 ppm ^5)

Formaldehyde .75 ppm .04 ppm .35 ppm ^5)

Acrolein .1 ppm .0001 ppm ®

Units

f/cc = fibers (>5 um length) per cubic centimeter of air S/mm2 = structures (>.5 um length) per square millimeter of filter paper ppm = parts per million in air ug/m3 = micrograms of contaminant per cubic meter of air ng/mS = nanograms of contaminant per cubic meter of air NA - Not Applicable

Footnotes:

1. "Site Workers" refers to all workers involved in the response/demolition of the World Trade Center. Listed values are Occupational Safety and Health Administration (OSHA) Permissible Exposure Limits (PELs), Time Weighted Averages (TWA) unless otherwise noted.

2. "Residents" refers to people living in the vicinity of the World Trade Center as well as all other potentially exposed workers not involved in the response/demolition

3. Resident screening value is based on Asbestos Hazard Emergency Response Act (AHERA)

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CONFIDENTIAL, CITY_21MC100_003423731 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008

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