When I was working at the Pareora Freezing Works, a few years ago, one of the sparkies there was repairing an Electric Forklift.
Smoko time came, so he turned off the the F/Lift and went to have a cup of char.
When he came back and switched it back on, it
shot through the wall in the workshop, as someone had tampered with the controls, during Smoko, it made one hell of a mess.