OSHA air monitoring summary report, October 2001

NYC 9/11 Public Portal Document

Oxides of Nitrogen: Sampling on employees manning the truck wash stations found no detectable levels of nitrous or nutric oxide

Metals: As of 10/19 OSHA has taken 261 air samples to monitor worker exposures to dusts, fumes, oxides, and other compounds of metals such as antimony, beryllium, chromium, cobalt, copper, iron, lead, manganese, molybdenum, nickel, vanadium, zinc, cadmium, magnesium, arsenic, and mercury. Results from these samples are generally well below the applicable OSHA limits. However, torch cutting and burning structural steel at the pile have resulted in instances of overexposures as follows:. copper (6); iron oxide (6); lead (1); and cadmium (3). Accordingly, OSHA is recommending that workers engaged in these operations wear appropriate respiratory protection.

Ionizing Radiation: A survey of the rubble pile was conducted on 10/22-10/23 to check for latent radiation with particular attention to alpha radiation. Preliminary results show no elevated levels.

Dioxins: The single sample taken by OSHA and analyzed by the EPA, representing exposure on the pile, showed elevated levels of dioxins. These levels were substantially higher than background levels but comparable to levels. found by the EPA on the nibble pile. The dioxins found here are emitted from the on-going rubble fire. OSHA does not have a worker standard for dioxins. Dioxins are considered collectively as suspect human carcinogens. Some of the individual compounds are considered to be blown human carcinogens. OSHA is performing additional sampling and will coordinate with EPA to more frilly characterize exposure around the rubble pile.

Polynucleated Aromatic Hydrocarbons: OSHA identified several elevated samples, three of which reached or exceeded OSHA’s PEL of .2mg/M^' These samples were taJcen on the pile. OSHA continues to strongly recommend the use of respiratory protection when working on the rubble pile.

Pending Analysis: In response to information about exposure to the combustion by-products of Freon 22 used in the air conditioning systems of WTC towers, OSHA conducted sampling for fluorides as HF. Results are pending.

CONFIDENTIAL, CITY_21MC100_001882220 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008 NYC-WTC_000178320