A crankcase explosion is caused by ignition of oil mist, itself created by the presence of a hot spot, which led to the evaporation of lubricating oil and its condensation into an oil mist. Its consequences can be severe, including death and serious injury to personnel and extensive damage to the engine. Oil mist detection/monitoring equipment is the prime protection for an engine. Should a crankcase explosion occur, the provision of effective explosion relief valves is the main means for mitigating the effects on people and to the engine.