Abstract: At 10:00 a.m. on August 20, 2009, a maintenance worker and his assistant were attempting to remove a substation, located inside a building, from service. The line side of the substation was supplied with three-phase power at 7,200 volts phase-to-phase or 4,160 volts phase-to-ground. The secondary side of the substation's transformer supplied power at 480 volts. Before opening the primary circuit, the worker placed a Square D Wiggy solenoid voltmeter, rated for use up to 600 volts, on one of the phase conductors. The 4,160-volt potential of the conductor was well over the meter's capabilities, and the meter failed immediately. An electric arc ensued, and the maintenance worker sustained partial thickness burns, also known as second-degree burns, to both arms. He was hospitalized. An investigation revealed that neither worker was properly trained or equipped to perform this task.