Abstract: On September 6, 2011, an electrician with the Alameda County General Services Agency, was part of a four-person crew trouble-shooting displaced insulators in 12KV "B" bus bar switchgear. After reviewing the panel circuit diagram, the crew shut off bus bar "B" and the team tested for power. Employee #1 checked the phases with a tick tester to ensure that the circuits were not energized. He then used an Ideal multi-meter (rated for 600 volts maximum) and found phase "A" to ground indicated 84 volts, Phase "B" to ground indicated 83.5 volts, and Phase "C" indicated 84.5 volts. To locate the source of the residual power, Employee #1 went to the back of the panel, retested the wires with the tick tester in the same sequence, and no power registered. As he placed the meter's positive prong on the phase "C" conductor and the negative prong on the ground conductor, an arc flash occurred. Employee #1 and two other employees were transported to Eden Medical Center. Employee #1 was transferred to St. Francis Hospital's burn unit, where he was admitted for treatment of second-degree burns. The other two employees were released after evaluation.