Letter regarding air quality monitoring results, 111 Broadway, Feb 2002

NYC 9/11 Public Portal Document

AKRF,Inc. 111-115 Broadway,New York,New York

of the laboratory results for aldehydes. A complete copy of the laboratory analysis report is included in Appendix B. 2.4 Asbestos Air monitoring for asbestos fibers was performed and samples were analyzed in accordance with USEPA AHERA protocol. Samples were collected by drawing air through a 0.45 µm pore Mixed Cellulose Ester filter utilizing a high volume sampling pump. The sampling pump was calibrated, utilizing a rotometer, with a representative sampler in line prior-to and after each sample collection. Samples were analyzed by Transmission Electron Microscopy (TEM). . The samples were delivered to, and analyzed by, AMA Analytical Services, Inc. (AMA) of Lanham, Maryland. AMA is a certified ELAP, AIHA, and National Voluntary Laboratory Accreditation Program (NVLAP) laboratory. Analytical results revealed airborne levels of asbestos fibers below the United State Environmental Protection Agency (USEPA) and New York State Department of Labor (NYSDOL) established clearance criteria for successful completion of an asbestos remediation procedure of 70 asbestos structures per square millimeter (s/mm2). All of the asbestos samples were also below the AHERA re-occupancy level of 70 asbestos structures per square millimeter (s/mm2). Table IV contains a summary of the laboratory results for asbestos. A complete copy of the laboratory analysis report is included in Appendix B. 2.5 Respirable Particulates and Silica Respirable dust is an airborne material, which is capable of penetrating the respiratory tract into the gas-exchange, non-ciliated region of the lungs. Samples were additionally analyzed for dust, quartz, cristobalite and tridymite concentrations. Cristobalite and tridymite are composed of the same chemistry as quartz, but have a different structure. Respirable particulates were sampled and analyzed in accordance with NIOSH Method 0600 and crystalline silica was analyzed in accordance with NIOSH Method 7500. The sampling method requires air to be drawn through a 5µm polyvinyl chloride (PVC) pre-weighed filter in a cassette filter holder affixed to an aluminum cyclone, utilizing a personal sampling pump. The sampling pump was calibrated, utilizing a rotometer, with a representative sampler in line prior to and after each sample collection. All samples were transported to, and analyzed by, Galson. All of the crystalline silica and respirable dust samples were determined to be below the OSHA, NIOSH and ACGIH exposure limits. Table V contains a summary of the laboratory results for respirable particulates and silica. A complete copy of the laboratory analysis report is included in Appendix A. 2.6 Volatile Organic Compounds Volatile Organic Compounds (VOCs) are a group of substances containing carbon and other elements, including hydrogen, oxygen, fluorine, chlorine, bromine, sulfur and nitrogen. VOCs easily vaporize at room temperature and are commonly used in adhesives, solvents, degreasers, cleaning solutions, dry cleaning fluids, components of pesticides and plastics, and are among the by-products of combustion. VOCs were sampled and analyzed in accordance with EPA Method TO-15. The sampling method requires the use of evacuated canisters. The canister uses its own vacuum to draw in the air sample, and the airflow is controlled by a regulator. All samples were transported to, and analyzed by, Galson.

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