NYC-WTC_000208747

NYC 9/11 Public Portal Document

liberty Mutual. Industrial Hygiene Measurement Results Contractor: __________ ______ ____________ Dates Covered^: 4/26/02 to 5/10/02 _____________________

Enclosed are the results from industrial hygiene air samples collected and/or direct reading instrument measurements recently made at your operations in the WTC recovery operation. These samples were collected by ATC Associates, Inc. These results have been provided without benefit of review by ATC for typographical errors. Analytical results have been peer reviewed by Liberty Mutual.

Samples having a worker’s name in the 'Worker” column are “personal” samples and were collected by having the worker wear the sampling device. Results from personal samples are representative of the time-weighted average exposure experienced by the worker. Any samples marked as “area” samples were collected in a fixed location. These samples give an idea of average contaminant concentration at the fixed location but do not necessarily represent worker exposure levels.

The OSHA Hazard Communications Standard and other OSHA standards require that you notify each worker who has participated in the industrial hygiene air sampling that the results are available and educate them about their work exposures.

If you have questions concerning the enclosed sample results or any questions concerning occupational disease exposures or controls, feel free to contact the Liberty Mutual Industrial Hygienist on duty @917-566-2576.

Donald A. Weber, Sr., IHIT Liberty Mutual Group

5/16/02

CC: Bovis - Ray Master DDC - Bob Adams/ Bruce Rottner LMIG - John Rabovsky LMIG - IH File ATC - Mike Donovan

1 Dates covered refers to the dates on which results were provided by the lab. Actual sample collection dates will vary.

CITY_21MC100_009250089

NYC-WTC_000208747