How NFPA 70E relates to the rules that bind you
NFPA 70E is not law. No state has adopted it as a binding regulation. It is still the document your work practices get measured against, and understanding why is worth ten minutes.
What OSHA does
OSHA sets outcomes. Employees must be trained in safe work practices. Energized parts must be guarded or the work justified. The rules say what must be true, not how to make it true.
What NFPA 70E does
NFPA 70E supplies the method. Risk assessment procedure, approach boundaries, incident energy analysis and PPE selection, energized work permits, the training content behind a qualified person determination. It is written by the people who need it to work in practice, and revised on a three-year cycle.
How they connect
OSHA recognises consensus standards as evidence of what a reasonable employer does. When an inspector asks how you decided a boundary or selected PPE, NFPA 70E is the answer that holds up. The General Duty Clause and the training rules are the mechanism through which it bites, which is why calling it optional is a mistake even though calling it law is also a mistake.
Which edition
The 2027 edition is current. Working to a superseded edition is a defensible position only until someone asks why, and it rarely survives the question.