Abstract: At approximately 10:30 AM on August 27, 2007, Employee #1 and Employee #2 were performing a regular maintenance on boiler heater (Teledyne Laars, Model # PW1670IN09C1AR, Serial # 1923823). After performing the maintenance, employee #1 turned on the ignition switch to relight the heater, however, the pilot did not come on, and he heard some rattling noise from the valve. So employee #1 turned off the switch and called his supervisor over the phone for further technical assistance. Employee #1 again turned on the ignition switch and asked the Employee #2 to bend down and see if the heater had ignited. As Employee #2 bent to see the pilot, a flare up occurred which burned Employee #1 and employee #2's face. This explosion disappeared after 1-2 seconds. Nothing else was burned or blackened in the boiler room where other 3 boilers were present. Both employees were taken to the Stanford Hospital where they were observed and released. It was determined that both employees suffered minor first-degree burns.