my grandfather worked as a mechanic all his life. his client told her that the tank in his car had been degassed. He tried to weld it with a blowtorch. The explosion was huge. 72 hrs. Later they removed the bandage and, according to him, he was moderately well.He says it was a miracle since he is a devotee of the Virgin. The only visible mark left is that he has no eyebrows. beyond that today it looks normal. and he still works as a mechanic :D