Please don't cross post. I am closing the other thread because this probably belongs here.
In the original thread you didn't mention the MCC or VFD, that makes a difference. Locking off the breaker / disconnect of a panel does NOT make it totally safe to be in it without PPE, so long as the LINE SIDE of the equipment is sharing the same space. So in an MCC bucket, if you only lock off the UNIT disconnect, it doesn't qualify as not needing PPE if the REST of the MCC is still live, because an arc flash event elsewhere could still propagate the plasma and blast pressure right into your face; the bus bar barriers are NOT intended to withstand that. The only way to avoid having to wear PPE to work on an MCC bucket is to power down the ENTIRE MCC, or to remove the bucket and work on it on the bench. The same is true in a VFD enclosure; a dropped tool or insulation failure on the line side of the disconnect would still have you exposed to the dangers (I personally have lived through that one, but I was lucky). So that's why I had qualified my earlier statement to say IF THERE IS NO LINE VOLTAGE, you don't need PPE. that is NOT the case of there are line power devices and the line power is still hot anywhere in the panel.