Abstract: At approximately 3:00 a.m. on July 13, 2009, Employee #1, a shift team leader, relieved a coworker, a laborer, for a dinner break. The coworker had been working on a high temperature ceramic melt furnace designated "Eagle" by the employer, and Employee #1 now assumed this role. Another coworker, a maintenance technician, had been clearing a jam in the furnace prior to Employee #1 beginning work on the furnace. The coworker began clearing the jam by idling the furnace at approximately 9:30 p.m. on July 12, 2009. The job of clearing the jam took approximately 6 hours during which time the coworker inserted a shop-fabricated tool called a basket in the back end of the furnace where parts exit. The purpose of inserting the basket was to lift a sealing material called angel hair up and out of the way so that a rod could be inserted into the furnace to clear the jam. After clearing the jam the coworker forgot to remove the basket, and with this device still in place the angel hair could not seal the furnace. Hydrogen is injected into the furnace during operation. At approximately 3:05 a.m. Employee #1 began working on the furnace a few minutes after it had returned to operating temperature air leaked into the furnace and mixed with the hydrogen. The flash fire occurred when the fuel and air mixture reached the appropriate level to ignite. Employee #1 was standing at the front end of the furnace where parts are inserted. Employee #1 was removing slack from a conveyor belt that runs the length of the furnace when a flash fire occurred in the furnace. Employee #1 received first-degree and second-degree burns to the wrists, arms, face, and neck. Employee #1 was treated for her injuries but was not hospitalized.