Abstract: At 10:30 a.m. on August 20, 2007, three employees of the L.A. City Department of Water and Power were installing a new electric service for a commercial building being constructed. They had installed switchgear and a transformer outside of the building in a parking lot. The switchgear was in a cabinet that consisted of three switches, one for each leg of a 34.5 KV, service. One of the employees touched an energized part with a tool which caused an arc flash. All three employees sustained second and third degree burns to their faces, hands, arms and stomachs from the arc flash. They were hospitalized at the L.A. County/USC Medical Center for treatment of their burns. They had been wearing fire retardant shirts but were not wearing hand, or face PPE.