NYC-WTC_000208228

NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan November 25, 2002 Wipe Samples for Dioxins Page 2 P. S. 124 Manhattan ATC Project No. 15-19125-0350

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 resul s for each sample. A copy of the laboratory analysis report is attached. The results are shown n the following table.

DIOXIN WIPE SAMPLE RESULTS 2,3, 7, 8 TCDD EQUIVALENTS - Nanograms per square meter (ng/m^) September 12, 2002 LOCATIOri /SAMPLE ID DIOXIN CONCENTRATION

Lobby-Main Entrance / DX-1 0.00

2nanoorl-allway by Room 222 / 0.000035 DX-2 3r3Tfo^allway by Room 307 / 0.00 DX-3 Blank / DX-4 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 concentrations on indoor surfaces ranged from 0.00 to 0.000035 nanograms per square meter (ng/m^). The levels found in all of these samples are below the NYSDOH guideline of 25 ng/m2.

It IS not possible to determine when the 2, 3, 7, 8 - TCDD equivalents detected in these samples was deposited. Dioxii samples were not collected from these locations prior to these samples therefore a background sample is not available for comparison purposes.

It IS our pleasure to provide these indoor environmental services to the NYC Department of Education. If you ha\e any questions about this report, please call (212) 353-8280, extension 212.

Sincerely, ATC Associates, Inc.

James R. Cohn, CIH, C ST Regional Manager Industrial Hygiene Division

Attachment

CITY_21MC100_003021112

NYC-WTC_000208229