N-N-N-N-never. yup, 480 volt one phase in each hand was the worst, tuck, rolled and ducked out of the way of several arc blasts.

A friend of mine was working in a lighting contactor panel last week though, someone turned a switch on and he leaned against a live 277 volt conductor. The crush of his muscle broke the socket of his upper arm (Nope, he ain't that big) as well as destroyed some tendons, he'll be out a while.