David, here’s my take on your question.
The US Occupational Safety and Health Administration deals primarily with safety issues, but does not so much address administration of certification and licensing of tradesmen. Whereas OSHA is a federal “umbrella” organization, this does not preclude states from having their own occupational-safety enforcement—usually adapted for regional conditions and historic aspects.
OSHA sections 29CFR1910.331, .332, .333, .334, .335 are often grouped together as dictating rudimentary electrical training for electricians and non-electricians in the workplace. Custodians use electrical appliances that have recognized electrical-safety considerations. Painters need to recognize exposed conductors normally isolated by elevation but reachable by ladder. These correspond to very basic concepts, and have become mandatory rules for places of employment that evolved from statically significant categories of injuries and deaths in industry.
For example, “qualified” electrical employees need to fundamentally understand what specific parts of electrical equipment are energized, at what voltage class they operate and procedures to test and secure the subject equipment before direct contact or adjacent work is attempted.
[§1910 generally excludes regulations unique to construction sites and equipment, which are primarily covered in §1926.] http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9908
A preamble states: The provisions of 1910.331 through 1910.335 cover electrical safety work practices for both qualified persons (those who have training in avoiding the electrical hazards of working on or near exposed energized parts) and unqualified persons (those with little or no such training)…