The Houston Chronicle has nice, one-page summary of relevant OSHA regulations for mechanics:
Automotive shop workers are especially vulnerable to chemicals and other workplace hazards, which is why the U.S. Department of Labor and the Occupational Safety and Health Act established workplace standards for auto mechanics and the shops they work in. Regulations cover everything from letting mechanics know their rights to making the proper equipment available to workers
While many mechanics grumble about the regulatory burden, OSHA regulations are based on industry-specific safety best practices developed in response to data on actual workplace injuries. Since OSHA came into being, workplace injuries and fatalities have impressively declined.