SANTA FE SPRINGS, Calif., Nov. 9, 2016 /PRNewswire-USNewswire/ -- Cal/OSHA has cited AAA Roofing by Gene, Inc. for serious safety violations following an asphalt tanker explosion in Santa Fe Springs that burned two workers and launched them 10 feet onto the ground. Both workers suffered third-degree burns. One worker's burns covered up to 36 percent of his body. AAA Roofing had been hired to repair the flat roof of a warehouse when the accident occurred on May 2, 2016. Two employees standing on top of a tanker truck were attempting to turn the truck's discharge pipe to face another direction. Cal/OSHA inspectors learned that the workers' foreman instructed them to heat the pipe with a propane torch to loosen it. The tanker was half-filled with hot liquid asphalt. Heated liquid asphalt releases flammable vapors. "Flammable vapors accumulated in kettles and tankers, if ignited, can burn or explode," said Cal/OSHA Chief Juliann Sum. "Employers must ensure that no source of ignition is permitted in any location, indoors or outdoors, where the concentration of flammable gases or vapors exceeds or may reasonably be expected to exceed 25 percent of the lower explosive limit." Cal/OSHA issued three workplace safety citations to AAA Roofing by Gene this week, with proposed penalties of $24,575. Two of the citations are serious, and one is regulatory in nature. One of the serious citations involves AAA's failure to ensure the tanker truck was equipped with a 42-inch guardrail. This could have helped ensure the workers did not fall 10 feet as they did. The other serious citation was for allowing a source of ignition to be introduced where the flammable gases exceeded 25 percent of the lower explosive limit. A serious violation is cited when there is a realistic possibility that death or serious harm could result from the actual hazardous condition.