OSHA has jurisdiction for industry. If you're a small contractor (<10), or a family owned enterprise you're off their books. But if you're hired for a larger project then then that project--and you--need to be compliant.
OSHA does not cover trucking and highway accidents, that's DOT, where the most job-related fatalities occur. There are state OSHA plans as well, where the Fed'l OSHA is not in force. Military and fed'l sites are still under Fed OSHA in state-plan states, and offshore.
