When I was a fireman I once made a run where a guy had been using a belt sander. It slipped and ran into his thigh, biting into his skin through his pants. About three inches of skin was caught between the belt roller and the housing. We had to take him to the ER with the belt sander attached to his thigh. Now, I made a lot of runs and saw some pretty egregious stuff, but nothing struck me as being any more painful than that.