Any guesses on what caused this raging dumpster fire? Turns out, a contractor working on a home remodel for a family in Colorado, had his crew throw oily rags into the dumpster. As the rags dried they began to heat up until they spontaneously combusted.
Spontaneous combustion of oily rags occurs when a rag or cloth is slowly heated to its ignition point through oxidation. A substance will begin to release heat as it oxidizes. If this heat has no way to escape, like in this dumpster, the temperature will raise to a level high enough to ignite the flammable vapors and ignite the rag or cloth.
Oil-soaked rags should never be disposed of in trash compactors, trash dumpsters, or ordinary trash cans. Instead, all oily rags must be disposed of in covered metal containers. A metal safety can with a self-closing lid manufactured specifically to hold oily waste is recommended. These safety cans should be placed at key locations (away from ignition sources) and should be emptied and properly disposed of regularly.