WayRob1956, learned that lesson many years ago.
Worked in a grocery store and a couple of us that turned off lights at night use it the breaker panel that many were hot to the touch. Electrician determined that screws holding breakers to hot buss were loose. Well he started tightening with the panel still hot! Well as he put screw driver to one screw it fell out and landed between the buss and tub!!!!
I never saw such a Fireworks Show even on the 4th of July!!!! He was shaken, but unharmed.