NYC 9/11 Public Portal Document
LIBERTY
MUTUAL
Industrial Hygiene Air Sample Results
Summary for Weeks of 12/21/01 toOl/04/02
Attached is a summary of the results of the samples collected by ATC associates at the World Trade
Center site for the specified week.
The vast majority of the samples collected by ATC are “personal samples”, meaning that the worker wore
the sampling device. The vast majority of results have shown exposure levels to be below occupational
exposure limits. The exceptions were;
An ozone concentration of 2.38 times the TLV on a torch cutter on the surface east of WTC 5
A sulfuric acid concentration of 1.18 times the TLV on torch cutter in the WTC 1 depression
A quartz concentration of 6.8 times the TLV on a jackhammer operator in the cable pit
An asbestos concentration of 100% of the TLV on a grappler operator in the vicinity of the
Bankers Trust building
Some of the columns in the attached summary may require explanation:
Analyte Class - This column includes general category of the agents (substances) which were sampled.
# of Samples - This indicates how many individual samples were collected fc.’ 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 the number of samples. However, most samples are
analyzed for more than one agent as follows;
Metals: Aluminum, antimony, arsenic, barium, beryllium, cadmium, calcium, chromium, cobalt,
copper, iron, lead, magnesium, manganese, nickel, selenium, silver, thallium, tin, titanium,
vanadium, and zinc. Metal samples are sometimes also analyzed for total particulate.
PAHs: Acenaphthene, acenaphthylene, anthracene, benz(a)anthracene, 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-butyraldchyde,
propionaldehyde, and valeraldehyde.
Acids; Hydrobromic acid, hydrochloric acid, hydrofluoric acid, nitric acid, phosphoric acid and sulfuric acid
Highest Analyte - The analyte found in the highest concentration with respect to its occupational
exposure limit.
Highest Result - The concentration of the highest analyte.
CITY_21MC100_003130709
NYC-WTC_000186529
OCR can misread numbers and units. Confirm readings against the page image before using them.