Abstract: At approximately 12:00 p.m. on November 14, 2003, the owner of a painting company and a licensed contractor doing business as a sole owner, and Employee #1, a helper, were working in a single-family residence that was being remodeled. At the time of the accident, Employee #1 and the company owner were doing a final clean up of the floor of a basement room, using 2 gallons of lacquer thinner, a flammable liquid. They had previously stripped the old coating off the floor using paint remover. The room measured approximately 17-ft-by-17-ft and was 7-ft high. A natural gas fired water heater in a utility room adjacent to the room ignited the vapors, which flashed back into the larger basement room. The company owner suffered burns and later died of his injuries. Employee #1 had been by an exit door when the flash back occurred, and escaped with minor burns to a thumb. Employee #1 was not hospitalized. (Original narrative does not list the owner as a fatality.)