NYC 9/11 Public Portal Document
Mr. Bernard P. Orlan Febmary 25,2002
Wipe Samples for Dioxins Page 2
Stuwesant High School (Manhattan) ATC Project No. 15-19125-0246'
Each sample was analyzed for sixteen (16) PCDD/PCDF isomers. The results for each isomer
were then converted to 2, 3, 7, 8 tetrachloro-dibenzo-p-dioxin (2, 3, 7, 8-TCDD) equivalents by
multiplying by an established equivalency factor. This provides a single value (in nanograms)
for the analytical results for each sample. Copies of the draft analysis reports are attached. The
results of the samples are shown in the following table.
DIOXIN WERE SAMPLE RESULTS
2,3,7, 8 TCDD EQUIVALENTS - Nanograms per square meter (ng/m^)
P*'Floor Lobby
Main Entrance 0.000022
2^*^ Floor Lobby
Bridge Entrance 0.000039
HVAC#2
Mixed Air Plenum 0.00057
Field Blank 0.00
The New York State Department of Health (NYSDOH) established guidelines for dioxin for the
re-occupancy of the Binghamton State Office Building following a PCB fire. The NYSDOH
guideline for dioxin on surfaces is 25 nanograms per square meter (25 ng/m^). The New York
State Department of Environmental Conservation (NYSDEC) has set 0.0006 parts per million ■
(ppm) as the allowable concentration of dioxin in soil. The EPA has established a residential
clean-up goal of 1 part per billion (ppb).
The levels found in these samples are below the NYSDOH guideline of 25 ng/m^.
It is not possible to determine when the 2, 3, 7, 8 - TCDD equivalents detected in these samples
were deposited. Dioxin samples were not collected from these locations prior to November 8,
2001, and therefore a background sample is not available for comparison purposes.
It is our pleasure to provide these indoor environmental services to the NYC Board of Education.
If you have any questions about this report, please call (212) 353-8280, extension 212.
Sincerely,
ATC ASSOCIATES^
James R. Cohn, CIH, CSP
Regional Manager
Industrial Hygiene Division
Attachment
CITY_21MC100_002896362
NYC-WTC_000226933
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