OSHA was created by Congress under the Occupational Safety and Health
Act, of December 29, 1970. Its mission is essentially to prevent work-related injuries, illnesses, and deaths.
Its statutory authority extends to most workplaces where there are employees and staff. State and government workers are excluded from Federal coverage. However, States operating their own workplace safety programs under plans approved by the U.S. Department of Labor cover most private sector workers and are also required to extend their coverage to the public sector.
OSHA regulations also permit states without approved plans to develop plans that cover only public sector workers. In these states, private sector employment remains under Federal OSHA jurisdiction.
Despite early difficulties, over time, manufacturers of industrial equipment have included OSHA-compliant safety features in new machinery, enforcement has become more consistent across jurisdictions, and some of the more unpopular rules have been repealed.
OSHA now has over 2000 inspectors across more than 200 offices, and nearly every working person in the US comes under its jurisdiction.