my neighbor is a boat mechanic. he has a medical condition that requires him to carry around a little bottle of oxygen with the tube that goes to your nose. he wears the bottle on a strap hanging over his shoulder. so I'm over ther B.S ing and he starts to weld something with his mig while the bottle is on and in use. seems unsafe to me. he tells me oxygen isn't flammable.. well no shit, but it just seems to me that adding pure oxygen to a burning situation is an accident waiting to happen what do you guys think??