NYC DOH hotline Q&A on building cleaning and HVAC maintenance,

NYC 9/11 Public Portal Document

made available? What other substances besides asbestos and fiberglass are being analyzed? The final report on the indoor air sampling should be completed by April. Substances being analyzed in the air samples are asbestos, fibrous glass and particulate matter. Substances being analyzed in the dust samples include asbestos, fibrous glass, silica, mica, calcite, gypsum, and the pH of this material.

• For how many hours did the air sampling occur in the DOH/ATSDR indoor air sampling? Don’t particles and substances increase during the night hours? Air pumps operated until they had sampled a large enough volume of air to meet the criteria in the sampling methodology. Typically, this time period was from 5-8 hours. The focus of this project was indoor sampling. The levels of dust and fibers indoors are most affected by the activities inside a residence, not the time of day.

• Why is there no mention of heavy metais tested indoors? Outdoor monitoring around the WTC worksite and indoor sampling conducted in schools near the site have, in general, not found elevated levels of heavy metals. Thus they are not considered a priority substance to be tested indoors.

• Is lead still being tested indoors? Yes. Lead sampling is still being conducted, particularly in schools. In the rare instances that it has been discovered in schools, those areas have been thoroughly cleaned. (What about outdoor testing??) • What companies conduct indoor air and dust testing? Names of environmental consultant firms can be found in the yellow pages under “Environmental Consulting”. The city cannot endorse specific contractors so we are not recommending any specific firms.

• What standard is the DOH using to determine “acceptable levels” for indoor air? How do you answer the charge from others that the standards being used are not protective of health, given the unique circumstances of the WTC collapse? In evaluating data from the WTC and the surrounding areas, the DOH is using a protective standard under AHERA (Asbestos Hazard Emergency Response Act) to evaluate the risk. This is the standard normally used to decide when children may re-enter school buildings following asbestos-removal activities. The Department of Environmental Protection requires an asbestos abatement if more than 1% of dust in a bulk sample contains asbestos fibers.

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