Abstract: Employee #1 was assisting his wife in her job as an independent contract oil/gas well pumper. They arrived at the well site and the wife took meter readings while Employee #1 looked at the oil holding tanks. As Employee #1 approached the oil/gas separator, an unfired pressure vessel ruptured. He was struck by the lowest portion of the vessel, causing external and fatal internal injuries. The investigation was terminated as there was no employee exposure and an employee/employer relationship could not be established. The cause of the source of the overpressure to the vessel was not determined.