The U.S. Federal Government (www.osha.gov)and some States have set standards for acceptable levels of asbestos fibers in indoor air. Many common building materials used before 1975 contain asbestos, such as some floor tiles, ceiling tiles, taping muds, pipe wrap, mastics and other insulation materials. Normally significant releases of asbestos fiber do not occur unless the building materials are disturbed, such as by cutting, sanding, drilling or building remodeling. Inhalation of asbestos fibers over long exposure times is associated with increased incidence of lung cancer. When asbestos-containing material is damaged or disintegrates, microscopic fibers are dispersed into the air. The symptoms of the disease do not usually appear until about 20 to 30 years after the first exposure to asbestos.