Abstract: At approximately 5:15 a.m. on October 1, 2012, Employee #1 volunteered to inspect the fuel oil level in a tanker. The tanker was an uninspected over the road DOT-406, 8000-gallon Fruehauf liquid non-pressurized tanker trailer that was stationary and was being used as an above ground fuel storage tank. The tanker contained an unknown amount of number-5 recycled waste oil. Employee #1 climbed the ladder on the rear of the tanker between the pump housing and the rear. He walked down the unguarded cat walk to the middle of the trailer and opened the 22-inch manhole cover. He knelt down and dropped his tape measure into the tank. The area around the tank manhole cover was dark and he used a butane disposable cigarette lighter and leaned into the manhole with the lit lighter. The tanker exploded and Employee #1 flew through the air on fire and landed head first onto the roof of the fuel oil transfer pump housing then bounced off and landed face first on the ground. Employee #1 received second and third degree burns, blunt force traumas, multiple broken bones, internal injuries. The employee was killed.