This testimony concerned the activities of NIOSH in regard to asbestos (1332214) hazards in the workplace. Workers have been exposed to asbestos while mining, milling, and transporting the mineral and while manufacturing and working with products which contain the substance such as protective clothing, mailbags, padding, conveyor belts, pipes, roofing shingles and gutters. Asbestos also has other special uses. Exposure to asbestos significantly increases the risk of contracting three serious diseases: asbestosis, lung cancer, and mesothelioma. Other causes of death associated with asbestos exposure include gastrointestinal cancer and laryngeal cancer. While it was not certain how asbestos causes disease, there has been thought that the surface properties, fiber size, and metallic content of the fibers may influence the carcinogenic properties of the substance. Exposures to asbestos among shipbuilders and seamen were highlighted in this report with mention being made of several epidemiologic studies conducted among workers in these occupations. The importance of occupational standards for asbestos exposure was discussed, and the history traced of the development of the standard. The current occupational exposure standard for asbestos permitted a maximum of two fibers larger than 5 microns in length per cubic centimeter of air. Based on recent evidence, NIOSH has requested that this standard be lowered to 0.1 fibers per cubic centimeter. NIOSH was also involved in establishing a Cooperative Center for Occupational and Environmental Health located in Baltimore to further studies in this area of concern.