NYC-WTC_000220337

NYC 9/11 Public Portal Document

Metals: OSHA has taken a total of 1117 samples (excluding bulk and blank samples) to monitor worker cxposuies to dusts, fumes, oxides, and other compounds of metals such as antimony, beryllium, chronriuin, cobalt, copper, iron, lead, manganese, mercury, molybdenum, nickel, vanadium, zinc, cadmium, magnssiuni, and arsenic. Results from these samples are generally well below the applicable OSHA limits. However, torch cutting and burning structural steel at the rubble pile have resulted in instances of overexposures as follows: copper (13); iron oxide (26); lead (17); antimony (1); and cadmium (2). Accordingly, OSHA is recommending that work^s engaged in these operations wear appropriate rcspiiatory protection. See information below for the specific counts in regards to merevTy.

Mercury OSHA has taken 224 air samples for inorganic mercury. No mercury was detected. Also, 36 bulk samples previously collected from rubble were re­ analyzed for mercury and none was detected. Additionally, 10 bulks were taken on 1/3, with one sample detecting mercury at C Qppm and nine samples did not contain mercury. 38 bulk samples were taken between i/S and 1/11/02; results indicate 0,1 to 02 ppm mostly to aiuuud the footprint of Bldg.-6, and in the pit between wrc tower 1&2.

ionizing Sadialiou: A Survey of the rubble pile was conducted on 10/22-10/23 to check for latent mdiation with particular attention to alpha radiation. Results show no elevated levels of concern from either known building latent radiation sources or any terrorist origin source materials.

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