Never let an Acetylene tank lay on it's side, or upside down.
Never get oil near pure Oxygen. Never use your Oxygen tank to fill anything (I heard of a guy who filled his tire, and yet improbably, survived it.)
Use soapy water to check for leaks.
Fill old fuel tanks with water if you have to cut or weld on them.
Teflon tape goes only on pipe threads, not in flare fittings, compression fittings, or anything else that isn't a NPT pipe fitting.
I should have worn ear plugs, I love to listen to music, can't hear it as well anymore.
Brains trumps brawn.
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