Abstract: An electrical contractor was remodeling the electrical service to a state office building. The contractor's employees were moving panelboards to a new electrical room located on the same floor. A shutdown of the building had been scheduled for that day and the following day; however, a large group had arranged a meeting for the auditorium in the building 9 months earlier. A decision was apparently made to continue work without locking out the electrical service. (After the accident, there was disagreement between the State and the contractor over whether the State ordered the contractor to work with the circuits energized. In any event, the State's project coordinator, who is responsible for authorizing electrical outages, did not check on the status of the lockout for that day.) One of the contractor's employees was connecting a neutral conductor to the middle panel's busbar mounting bracket, apparently because the conductor was loose and because the contractor was concerned that it might contact the busbar. The owner of the contracting firm was installing a circuit breaker in the middle panel. Although the circuit breaker he was working on was open, the main disconnect switch for the 480-volt, 1200-ampere, three-phase, four-wire panel was closed. As the contractor, whose only protective equipment was a pair of safety glasses, was moving out away from the panel, an electrical fault involving all three phases occurred. The contractor was burned on the left side of his face by the ensuing electric arc. He was hospitalized for his injuries. The other employee, who was kneeling low near the neutral connection to the panel's busbar frame, was not injured. The cause of the electrical fault was not determined conclusively. However, there was circumstantial evidence that it occurred when an 8-inch-long metal tie wire dropped into the panel.