Labor relations correspondence regarding site locations, Sep 2001

NYC 9/11 Public Portal Document

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Interpretation of results: Measurements of Carbon Dioxide were taken at al! interior room sample locations. Carbon dioxide measurements indicate whether there is sufficient air exchange within an occupied space. By comparing the outdoor spot readings to the Interior readings, you can estimate a "lag time".

Also. ASHRAE, NIOSH and GSA FPMR standards are NOT law. Only the OSHA PEL is a "legal" requirement. However the "spirit' of an indoor air quality evaluation is to evaluate ths indoor environment from both a comfort and health perspective and provide recommendations which will improve the environment.

Both ASHRAE Standard 62-1999 (The American Society of Heating, Refrigeration, and Air Conditioning Engineers) and the GSA FPMR (Federal Property Management Requirements) recommend levels below 1000 ppm for comfort and general purging of natural and artificial irritants.

We found the levels of carbon dioxide to be below 1000 ppm at all locations, showing sufficient air exchange.

Carbon Monoxide readings were taken using a Kane-May direct reading instrument, electronically zeroed, and sensitive to 1 ppm of CO. Levels measured throughout the facility were at non-detected (less than 1 ppm). This indicates vehicular traffic exhaust is not directed into the air distribution system, and since there were no other sources of combustion or heating, carbon monoxide is not a concern in this suite.

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