OSHA’s final rule to protect workers from exposure to respirable crystalline silica was published in March 2016 and comprises two standards, one for construction and one for general industry and maritime. The respirable crystalline silica construction standard became enforceable on Sept. 23, 2017. The standard established a new 8-hour time-weighted average permissible exposure limit of 50 µg/m3, an action level of 25 µg/m3, and ancillary requirements. The new PEL is approximately 20 percent of the previous PEL for construction.
OSHA previously published a compliance guide (PDF) intended to help small business employers comply with the respirable crystalline silica standard for construction. Different sections of the guide correspond to the major provisions of the silica standard for construction. The guide’s sections include information on specified exposure control methods, alternative exposure control methods, respiratory protection, housekeeping, medical surveillance, and more.