Asbestos is a human carcinogen with no safe level of exposure. Asbestos exposure can lead to serious diseases such as asbestosis, lung cancer, and mesothelioma. In 1973, EPA issued the Asbestos National Emission Standards for Hazardous Air Pollutants (NESHAP) to protect human health by reducing exposure to asbestos during building demolitions and other activities. According to the Asbestos NESHAP, regulated asbestos-containing material (RACM) must be removed by specially trained technicians prior to demolition. RACM does not need to be removed when the building is structurally unsound and in danger of imminent collapse. This method reduces the release of friable asbestos by removing asbestos intact. Beginning in 1999, EPA considered alternative methods to augment the Asbestos NESHAP. These demolition methods, such as the Fort Worth Method and the Alternative Asbestos Control Method (AACM), leave some or all RACM in place. Demolition equipment applies mechanical forces that shred the RACM, potentially releasing asbestos fibers into the environment and endangering public health. Buildings are wetted during demolition in an attempt to limit the release of asbestos fibers. However, EPA has not approved or shown that these wet methods are protective of human health. In July 2011, EPAs Office of Research and Development ended its research on the AACM due to technical deficiencies.