Abstract: A 59-year-old supervisor with over 37 years of experience (including 2 years at this site) was installing fire-barrier caulking and cardboard at the cable entry to a 12-kilovolt outdoor switchgear substation. He had placed the cardboard at the base of the cables and was placing the caulking on the cardboard. The employee was not using any electrical protective equipment. A phase conductor faulted, and the ensuing electric arc ignited the employee's shirt and coveralls. The employee suffered serious burns over 30 percent of his body, including his hands, arms, chest, face, head, and shoulders. He was hospitalized for these injuries. The cause of the electrical fault could not be determined.