Appreciate the info, everyone - my scenarios are hypothetical, and in some of these examples, I AM the boss, so it's not about the boss not caring - it's the opposite of the boss not caring.
What I'm trying to is establish if our workplace policies HERE apply EVERYWHERE, and to violate them on the road is the same as violating them here, whether or not OSHA is involved.
But OSHA does insist we have a safety policy in place.
More practically - I have some renegade service techs who insist they are In The Clear as long as they adhere to the local policies. I believe that to be incorrect - but I'm having a hard time finding real proof of that.