ABSTRACT

Relating the airborne concentration of a material re-entrained from a surface and the surface dust concentration has been the focus of study for a number of different materials in addition to asbestos. Re-entrainment of asbestos dust involves a redispersion or resuspension of fibers resulting from a variety of activities. In the Yale University Art and Architecture Building where chrysotile asbestos-containing material had contributed asbestos fibers to the dust on top of books, the fiber concentration during quiet conditions was found to be 0.02 f/cm3. Carpet cleaning of an artificially contaminated carpet using regular dry vacuuming methods produced airborne asbestos concentrations of 0.09 s/ cm3. Some of the data can be found in a report compiled by the Health Effects Institute—Asbestos Research Literature Review Panel. More data obtained using transmission electron microscopy analysis showed levels of 30 s/cm3 for activities disturbing settled dust originating from the fireproofing in a warehouse that included driving a forklift.