Abstract: An electrical contractor was working at a rubber manufacturing plant. The contractor was modifying the wiring for a 150-horsepower mill motor, installing the wiring for another mill, making repairs to some conduit, and installing limit switches. The circuits involved were 120 to 240 volts single phase, 250 volts three phase, and 480 volts three phase. One of the contractor's employees had opened the doors to a cabinet enclosing circuit parts energized at 480 volts so that he could explain his work and the problems he encountered to an electrical inspector. (The panel was manufactured by the A-C Supply Company. It was rated 480 volts, three phase. It bore Serial No. 42006-C.) The working space in front of this cabinet was 0.76 meters deep and 2.4 meters wide. The employee, who was a licensed electrician, contacted the 480-volt busbar as he was explaining his work to the inspector. The electrician was electrocuted.