Google search for the picture of the US Soldier who blew off his hand using a [I think] .50 cal round as a hammer...

Then stick to Propane.

I've edited the thread title and the original post. I work in the safety industry servicing breathing air systems and anything involving pure oxygen scares the living shit out of me. I know a few guys who have lost various body parts servicing the medical gas cylinder and they've blown up due to improper procedures. There is no "that was close" when working with oxygen. My shop won't even touch the stuff.