Abstract: Four employees were installing new cables for an emergency generator. Two of the employees were outside, removing the temporary power cables and coiling them up. These two employees were also running new permanent cables into the emergency generator trailer. The other two employees, an apprentice electrician and a coworker, were working inside the bottom section of a 480-volt, 4000-ampere switchboard, connecting the permanent cables for the emergency generator. In a prejob meeting, the coworker told the apprentice that the disconnect was open, deenergizing the section they were going to work on, but that the upper half of the switchboard was energized. The apprentice and his coworker used test equipment and determined that a 480-volt, 1-ampere meter circuit was energized. The disconnect for the meter circuit was a toggle switch. The meter circuit, which was not protected by the ground-fault circuit interrupter protecting the generator output, included three fuses in a fuse block, three transformers, and two meters. The coworker turned off the meter circuit disconnect switch and placed cardboard over the switch, the fuse block, transformers, and associated wiring. The cardboard was intended to protect the equipment from damage and to protect the workers from electric shock. (The employees did not have any rubber insulating blankets or matting or plastic insulating sheeting in their truck.) The two employees were about to connect the last of the cables, the neutral conductor, which was located near the back of the switchboard, but the cable was too short and needed a splice. The coworker went to the truck to get a crimper and duct tape, while the apprentice remained at the switchboard. When the coworker returned, he saw the apprentice lying on the concrete floor with his head and arms inside the switchboard cabinet. The coworker also noticed that the cardboard that had been covering the meter circuit had slipped further inside the cabinet and that the meter circuit disconnect switch was closed. The left arm of the apprentice was resting on the fuses. The coworker tried to pull him out of the switchboard but failed to move him. The coworker and the remaining two employees pulled the apprentice electrician out of the switchboard cabinet, and one of them administered cardio-pulmonary resuscitation. However, their efforts to rescue the apprentice failed; he was pronounced dead at the hospital. He had been electrocuted.