Abstract: A maintenance electrician in a large wheel manufacturing plant was replacing circuit breakers in a panelboard. The circuit breakers had been damaged during the failure of the transformer fuses protecting the building's electrical service. The maintenance electrician removed all the breakers from the panelboard before a service crew from the electric utility arrived and replaced the transformer fuses. That crew left after checking to see that the main circuit breaker was still open. The maintenance electrician checked the position of the main circuit breaker handle and checked the busbars on the panelboard with a multimeter before he started installing the replacement breakers. The panelboard became energized, however, and an electrical fault occurred when the electrician installed one of the breakers. The maintenance electrician suffered second- and third-degree burns on his face and both forearms from the ensuing electric arc. He was hospitalized for his injuries.