HVAC cleanup proposal for residential units, Feb 2003

NYC 9/11 Public Portal Document

residents.

12) Will you be using micro vacuuming sample collection in your studies? There is ongoing scientific debate about the usefulness of micro vacuum samples since there is no risk-based standard for asbestos in dust. EPA will collect samples in the unoccupied building using micro vacuuming techniques for study and screening piuposes. We will also use other techniques such as wipe samples for certain compounds.

13) What does EPA recommend people do with things that can't easily be cleaned, like carpets and drapes? If an apartment was heavily impacted by dust or debris from the WTC collapse, residents may want to replace porous items such as carpets and upholstered furniture. Asbestos is tough to get out of carpets and drapes; that is why we have recommended repeated cleaning.

As part of our pilot study, we will be evaluating the effectiveness of removing asbestos as well as other compounds from porous surfaces.

14) What does EPA recommend people do with their air conditioner? EPA is working with the state and city Departments of Health on guidelines for cleaning individual air conditioning units. The city will be conducting an evaluation of central (HVAC) air conditioning systems in consultation with the American Society of Heating, Refrigeration and Air Conditioning Engineers.

15) When will the pilot cleaning and background studies be completed? The study of indoor air is extremely complex. There are few indoor air standards already set. It is difficult to analyze for certain conditions indoors and there are no accepted sampling protocols. That is why we expect it will take between 18 and 24 months to complete EPA's pilot cleaning and background studies. It is also why we are taking a dual approach -- offering cleanups now and continuing to evaluate.

It will also take us time to get scientific support and comments on our studies. We are in the process of procuring the services of the contractors who will do the cleanups, testing and the analysis of the samples. We will need to get access to residential spaces. We will need to conduct a comprehensive review of various studies and compare the results.

As we conduct the studies we will keep the public informed about any new information that is valuable in the short term. Any identified refinements to cleaning will be translated into recommendations, which will be widely distributed. In the meantime, we recommend continued wet wiping, wet mopping and the use of HEPA vacuums.

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