Abstract: At approximately 10:00 on August 14, 1996, Employee #1 and a crew were assigned to rebuild a rotary selector valve. All input lines were locked and tagged out. A vacuum truck was present. The line was connected to the drain port and vacuuming was started and terminated four to five minutes later. The bolts holding the cap were removed but the cap stuck in place. A pry bar was used to remove the cap. The pry bar moved the cap about one inch and then the cap came off with explosive force. Hot oil sprayed on the crew. Paramedics were called and Employee #1 was transported to the Sherman Oaks Burn Center where he was hospitalized. Four coworkers were treated and released.