Tip from my old AF jet engine mechanic days - take off your watch & any rings when working around equipment, especially if you're up on a ladder, stand, or scaffolding. We were shown pictures in tech school of guys with the meat torn off their fingers when not obeying that rule.
Yup had a motorcycle tech that worked for me lose his ring finger. He said he couldn't take his off because his wife said so...the chain and rear sprocket disagreed. Worst part was, she was screwing around on the poor fella. Now his finger and his wife are gone. isn't life ironic?