Abstract: A power plant operator was working in a high voltage switchgear room. The employee had been assigned the task of installing earthquake clips inside the metal-clad, 4160-volt switchgear. The employee opened the rear of the bus section, exposing the bus and current transformers. The employee believed the current transformers to be step-down transformers. He obtained a tester rated at 600 volts and applied it to the current transformer terminals. The tester failed, and the ensuing electric arc burned the employee, who became engulfed in flames. The employee was severely burned on his arms, torso, and face and was hospitalized for his injuries.