An official EPA commentary on the development of the RRP sheds some light. (Both it and the 20-page rule are part of a 79-page document the agency has made available to the public. You can download a copy at epa.gov. According to this commentary, the EPA did not intend to approve the use of inexpensive vacuums retrofitted with HEPA filters. Such vacuums “are not necessarily properly sealed or designed so that the air flow goes exclusively through the HEPA filter,” the agency has found; instead, the vacuum should be designed for the “integral use of HEPA filters” (see page 46 of the pdf). The RRP requires vacuum cleaners to be designed “so that all the air drawn into the machine is expelled through the HEPA filter with none of the air leaking past it” (page 69).
This 79-page document contains the new lead rule itself (which runs about 20 pages), commentary about its development, text from the lead-hazards pamphlet that renovators are required to give homeowners, and lots of other information. You can download a pdf from the EPA’s Web site (epa.gov).
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