I'm struggling with the example of the pill conveyor. If LO/TO is for the inadvertent startup of equipment i.e. controls malfunction why would it be safe to use an e-stop or sorts? I also struggle with the comment NFPA 70E is for protecting electrical workers.
There are numerous ways of applying Machine Safety Systems that protect workers with tested and certified systems allowing routine machine entry for inspection, cleaning, clearing tasks during normal operation. Those systems have checks, cross checks and re-checks, along with established re-start routines that ensure worker safety, WITHOUT having to power down the entire machinery. Although not
yet codified here in North America, that is the standard in the rest of the world and because of that, it is already ALLOWABLE by OSHA. At some point those Safety Systems will be codified here as well, just not yet.
But that is NOT about protecting an ELECTRICAL worker who will have their hands in the ELECTRICAL equipment. For that, you MUST have a means of isolating all electrical energy away from the enclosure being worked on, as well as any potential for Arc Flash blast pressure. So that makes LO/TO for electrical work DIFFERENT from machine safety systems. Yes, if you use electrical LO/TO for any kind of machinery process work it's perfectly legit, just possibly impractical for routine operations.