Abstract: At 1:30 p.m. on March 23, 2009, Employee #1 was in the pilot equipment laboratory room at the Lockheed Martin Aeronautics Company calibrating the oxygen fill system high pressure gauges with an oxygen laboratory gauge test kit. Employee #1, following the oxygen test procedures, pressurized the system to 1,900 psi as shown on the indicator. When Employee #1 pressurized the system, from 1,950 psi to 2,000 psi for precision, one of the hoses failed, leaking oxygen. This resulted in a fire and explosion in the laboratory equipment system weld valve set up. Employee #1 burned his right hand from the fire, and Employee #2, Employee #3, and Employee #4 helped Employee #1 to the water in the sink to cool his burned hand. Employee #2 then called the Fire Department and ambulance. Employee #1 was taken to Antelope Valley Hospital and was then transferred to the Sherman Oaks Burn Center, where he was admitted on March 26, 2009 for two days. Employee #1 received second- and third-degree burns to his right hand.