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

1.0 INTRODUCTION AKRF, Inc. (AKRF) was retained by Rosenman & Colin LLP to perform Indoor Air Monitoring within 111-115 Broadway in New York City. The project site consists of two (2) twenty-one story buildings; 115 Broadway is located north of 111 Broadway, and Thames Street runs between the two buildings. The buildings are approximately 98 years old and are mirror images of each other. Two Heating, Ventilation and Air Conditioning (HVAC) rooms are located on each of the floors. The HVAC rooms are located on the south side of 115 Broadway and on the north side of 111 Broadway, both overlooking Thames Street. It is our understanding that the grills that allow the flow of fresh air into the HVAC rooms have been closed since the destruction of the World Trade Center on September 11, 2001. The windows are original to the buildings and are operable, but do not provide an airtight seal. It has been expected that outside air and particles could enter the buildings through closed windows. Various floors have installed new (and presumably air-tight) windows within the original windows. AKRF collected air samples for laboratory analysis at sixteen locations throughout the project site between November 26 and 30, 2001. The air samples were analyzed for the following constituents: Volatile Organic Compounds (VOCs), Polycyclic Aromatic Hydrocarbons (PAHs), metals, Aldehydes, asbestos fibers, silica, respirable particulates and dioxins. In addition, temperature, Relative Humidity, Carbon Dioxide and Carbon Monoxide concentrations were measured throughout the buildings using a Metrosonics aq-5000 direct read meter. The observed concentrations were compared to established occupational exposure values required by the United States Department of Labor, Occupational Health and Safety Administration (OSHA). OSHA has established permissible exposure levels (PELs); the values that an employer may expose an employee to for a normal eight-hour workday, 40-hour workweek, 50-week workyear, over a normal work lifetime. Other occupational exposure values are the National Institute for Occupational Safety and Health (NIOSH) recommended exposure levels (RELs) and the American Council of Governmental Industrial Hygienists (ACGIH) threshold limit values (TLVs). Both the RELs and TLVs are intended to cover similar environments as the PELs. The American Society for Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE) has developed guidelines and recommendations for providing acceptable indoor air quality. The ASHRAE guidelines are provided within various Standards providing for acceptable environmental conditions and ventilation.

2.0 TECHNICAL OVERVIEW The following is a general profile of the air monitoring execution and results. 2.1 Polycyclic Aromatic Hydrocarbons Polycyclic aromatic hydrocarbons (PAHs) are a class of compounds formed during incomplete combustion of oil, coal, gas, garbage and other organic substances. PAHs are found in petroleum and related products and are manufactured for use in dyes, insecticides, solvents and asphalt. PAHs were sampled and analyzed in accordance with NIOSH Method 5506. The sampling method requires air to be drawn through a 2 micrometer (µm) Teflon membrane filter and an XAD-2 sorbent tube containing collection resin 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. Immediately after sampling, the membrane filter was transferred to a culture tube and the sorbent tube was capped. The culture tube and sorbent tube

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