Abstract: A boiler operator was lighting a burst wood-fired boiler. The fire in the boiler had gone out because of a jam-up of the boiler's carburetor, which prevented more chips from falling down into the boiler. He took a pile of wood chips and placed them inside the boiler, just inside the door openings. He then extracted 0.25 gallon of hydraulic fluid from a 50-gallon container, pouring it into a 5-gallon container. He opened the boiler door and threw the hydraulic fluid in onto the pile of wood chips. The hydraulic fluid contacted hot ash, causing it to ignite. The flame blew back at him because he had failed to turn off the induced draft and combustion air fans. He received first-degree burns to his nose and hands. Management has instructed employees to first shut the fans off. No personal protective equipment had been worn while lighting the fire.