Abstract: On January 23, 2002, Employee #1, an electrician, and a coworker-helper were tasked with removing and replacing a defective emergency generator transfer switch for an elevator in a nursing home. Due to the age of the equipment, the switch had to be replaced. In order to maintain power to the building utilization equipment, it was necessary to reroute some of the wiring to the boiler room. The breaker to the switch was turned off, and the operation was completed. At this time, the generator needed to be reset to supply power to the boiler. Apparently a group of bunched "buck tailed" wires had shorted, tripping the breaker. A building engineer, who was in the boiler room, heard a "boom". The breaker had been damaged by the short, and Employee #1 and his helper went to their employer's shop to obtain another amplifier breaker. Upon returning to the nursing home, Employee #1 began removing the nine nuts holding the defective breaker in place when an arc blast occurred. He suffered first-, second-, and third-degree burns on his face, neck, chest, arms, and hands. During subsequent interviews, Employee #1 acknowledged that the panel had not been deenergized prior to starting the work. (It was reported that the panel could have been deenergized at a later time, but not at the time that the work was being performed.) He also stated that he and his employer had worked on jobs where the equipment had been de-energized or locked out. Causal factors of this accident include the employer's failure to ensure that lockout and tagout procedures were used, and the employer's failure to provide and ensure the use of appropriate PPE. The employer also did not have a written procedure in place.