Abstract
The risk of human exposure from asbestos-containing material is directly related to the condition of the material, custodial/maintenance activities, and the methods used to reduce the potential exposure to workers, bystander employees, and occupants of the area containing the asbestos. Many consider floor tile to be nonfriable, which is in accordance with the National Emission Standards for Hazardous Air Pollutants regulations, although there is some documentation of fiber releases from deterioration of such asbestos-containing materials during polishing, removal, or routine walking, due to the friction generated by such activities. This study evaluates several commonly used procedures for removal of floor tile and quantifies the fibers released during those procedures using data obtained by analyses from phase contrast microscopy and analytical transmission electron microscopy. These data document that fibers are released when floor tile is broken and/or abraded during removal procedures. Fiber levels vary with the aggressiveness of the procedures. A considerable percentage of the asbestos fibers identified by the analytical transmission electron microscopy methods specified in the Asbestos Hazard Emergency Response Act are below the size that can be detected by phase contrast microscopy and which are also the most easily respired due to their physical characteristics.