Back in the 80's, when I was in High School, me and a mate were gas welding a patch in the lower front guard of his Anglia van. He was sitting on a beer crate with his running shoes on and positioned just below where he was welding. Little did we know but there had been an earlier repair done with lead and when it got hot enough the whole section collapsed onto the top off his shoe, instantly melting through the mesh material and landing on the top off his foot. The whole neighbourhood learned some choice new words that day and we learned that you always check the metal before welding and never leave your feet below what you are working on. Needless to say it made an awful mess of his foot.