NYPD Access Policy for Building Owners and Contractors Oct 2001

NYC 9/11 Public Portal Document

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Industrial Hygiene Air Sample Results Summary fix- Weeks of 11Z25 and 12/2

Attached is a summary of toe results of toe samples collected by ATC associates at toe World Trade Center site tor toe specified weeks.

Sampling tor hydrogen sulfide around toe area of toe south bridge was begun during toe week of 12/2. This area has been a source of frequent complaints about “rotten egg” odor. Out of toe 8 samples collected in that area, one sample showed a concentration of 16 ppm, which is below toe OSHA ceiling PEL of 20 ppm, but above toe 8 hour TLV of 10 ppm. This was an area sample taken near a suspected odor source (a storm sewer opening) so it does not represent worker exposure. However, in response to this elevated result, we have included both personal and area samples for hydre^en sulfide in our sampling plan. The results of toe other samples collected in toe area were either very low or too low to be quantified.

The vast majority of toe samples collected by ATC are “personal samples”, meaning that toe worker wore toe sampling device. The vast majority of results have shown exposure levels to be below occupational exposure limits. The exceptions were:

A lead concentration of 2.3 times the PEL cm a grappler operator cm 10/17 A quartz concentration of 5 times the PEL cm a laborer during concrete demolition cm 11/16 A quartz concentration of 1.5 times the PEL on axurete mixer operator on 11/19

Following is an explanation of the columns in the attached summary:

Agent Class - Hus column includes general category of the agents (substances) which were sampled.

# of Samples - This indicates how many individual samples were collected for the agent class listed.

# of Analytes - This is the number of individual analysis performed. If only one analyze is determined on each sample, then the number of analytes will equal toe number of samples. However, most samples are analyzed tor more than one agent as follows:

Metals: Aluminum, antimony, arsenic, barium, beryllium, cadmium, calcium, chromium, cobalt, copper, ir<m, lead, magnesium, manganese, nickel, selenium, silver, thallium, tin, titanium, vanadium, and zinc. Metal samples are sometimes also analyzed fix- total particulate.

PAHs: Acenaphthene, acenaphthylene, anthracene, benz(a)antfaracene, benz(b)fluoranthene, benzo(a)pyrene, benzo(ghi)perylene, benzo(k)fluoranthene, chrysene, dibenzo(a,h)anthracene, fluoranthene, fluorene, indeno(l,2,3-cd)pyrene, naphthalene, phenanthrene and pyrene.

Aromatics: Benzene, ethyl benzene, toluene, and xylene.

Silica: Respirable dust, quartz, and cristobalite.

Aldehydes: Acetaldehyde, acrolein, benzaldehyde, formaldehyde, n-butyraldehyde, propionaldehyde, and valeraldehyde.

Acids: Hydrobromic acid, hydrochloric acid, hydrofluoric acid, nitric add, phosphoric acid and sulfuric acid

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