Abstract: An employee was hanging drywall in a tenant improvement construction project. He was working with a helper and his supervisor. The drywall installer was standing on the fourth step of a 2.4-meter-tall, Werner Class 1A, double-sided stepladder. The stepladder had four rubber feet. The helper was on the other side of the ladder, holding his Hilti Kwik Driver screwdriver (Serial No. 197338/KT). There was no electrical power in the work area, so the tool was connected by an extension cord set to a permanent outlet that was down the hall about 10 meters. The tool had a ground fault that energized its case. (The voltage was later measured to be 31.5 volts with the tool off.) The installer uttered "pipe" twice (in Spanish) and slumped over the top of the ladder, unconscious. He had been electrocuted. The employee's forehead had contacted an overhead condensate drainpipe, which provided a path to ground. The helper had been holding the screwdriver against the ladder, energizing it.