WTC Daily Report Memo, Oct 30, 2001

NYC 9/11 Public Portal Document Fa>rt2i*2'25998T5v^^ 31 2001 10:d0 P. 02

OSHA SAMPLING RESULTS SUMMARY AS OF 10/24 Asbestos: A total of 587 air monitoring samples for asbestos have been taken. From 9/13 -9/22, 177 samples were taken in the financial district. They were taken on OSKA personnel as they walked within certain predetermined zones. Results revealed asbestos concentrations ranging from. ND to .037 f'ce., well below OSHA’s permissible exposure limit'(PEL) of .1 f/cc. After 9/22, sampling focused on the rubble pile and those wo.i-kers working on^or immediately next to it. 53 of 410 samples exceeded OSHA’s limit vna PCM analysi.$. However., upon further analysis using, discriminating counting methods and/or TEM analysis, the"number'of asbestos fibers found dropped dramatically to below detectable levels or well below .1 f/cc. Carbon Monoxide: 41 personal samples.of workers on the nibble pile showed results ranging from I ppm to 34” ppm well beTow the OSHA 50 ppm permissible exposure limit Noise; OSHA has been conducting noise monitoring in the nibble pile. Twelve personal samples have been conducted on employees performine (or working near) various operations such as jack hammering, Employee’s exposure to the noise range from 80.6 dBA to 89 dBA. OSHA’s permissible noise exposure for construction is 90 dBA Respirable Silica; As of October 22, the overudiehning majority of the 189 silica samples show no detectable levels of airborne sifica. The highest sample result was approximatelv tMcc the OSKA limit, whereas the next highest level was less than half of libs limit. Both of these levels were found on personnel working in the rubble pile; an area where OSHA continues to encourage the use of respirator^' protection. Volatile Organic Compounds: OSHA has taken 173 samples for (VOC.$) such as acetaldehyde, acrylomlrile, acrolein, benzene, 2-butanone, chlorodiphenvl ’(PCB), ethyl benzene, fonnaldehyde, hexone, isocyanates e.g, (MDI)( HDl), perchloroethyiene. styrene, toluene, trichloroethylene, vinyl chloride and xylene. Screening samples initially showed elevated levels of some organic chemicals resulting from the fires burning in the rubble pile. Subsequent personal and area samples show worker exposure levels to be below OSHvV limits. However, one persona! sample result for benzene was found to be at the 8hr OSHA Allowable Limn concentration of Ippm. This was found on a • backhoe operator moving debris. 7

Oxides of Nitrogen; Sampling on employees manning the truck wash stations found no detectable levels of nitrous or nitric oxide Metals: As of 10/19 OSHA has taken 261 air samples to monitor worker exj^osttres to dusts, fumes, oxides, and other compounds of metals such as antmionX',' beryllium, chromium, cobalt, copper, iron, lead, manganese, molybdenum, nickel, vanadium, zinc, cadmium, magnesium, arsenic, and mercury. P.esults 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 overexposur&s 'as follows: copper (6); iron oxide (6); lead (i); and cadmium (3). Accordingly, OSKA is recommending that worker.? engaged in these operations wear appropriate respirator}' protection.

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