Abstract: Employees were sealing a wood floor in a bathroom in a new addition to an existing building. The employees had no Class I, Division I, or Division II electrical equipment. The light being used for general illumination was lying on the floor with no bulb guard installed. Only one window and door were open in another room and the ventilation was inadequate. No respirators or other personnel protective equipment, such as chemical-type splash goggles or full face shield, or impermeable apron and gloves constructed of nitrile rubber, neoprene rubber or polyvinyl alcohol, were being used in the bathroom. A flash fire occurred when the vapors from the sealer ignited, killing Employee #1.