facilities. In maritime transport, the regulations for the use of LNG as a marine fuel are set out in the IGF Code. In its liquid state, LNG is not explosive and can not ignite. For LNG to burn, it must first vaporize, then mix with air in the proper proportions (the flammable range is 5 percent to 15 percent), and then be ignited. In the case of a leak, LNG vaporizes rapidly, turning into a gas (methane plus trace gases), and mixing with air. If this mixture is within the flammable range, there is risk of ignition, which would create fire and thermal radiation hazards. Gas venting from vehicles powered by LNG may create a flammability hazard if parked indoors for longer than a week. Additionally, due to its low temperature, refueling a LNG-powered vehicle requires training to avoid the risk of frostbite. LNG tankers have sailed over 100 million miles without a shipboard death or even a major accident. Several on-site accidents involving or related to LNG are listed below: October 20, 1944, Cleveland, Ohio, U.S. The East Ohio Natural Gas Co. experienced a failure of an LNG tank. 128 people perished in the explosion and fire. The tank did not have a dike retaining wall, and it was made during World War II, when metal rationing was very strict. The steel of the tank was made with an extremely low amount of nickel, which meant the tank was brittle when exposed to the cryogenic nature of LNG. The tank ruptured, spilling LNG into the city sewer system. The LNG vaporized and turned into gas, which exploded and burned. February 10, 1973, Staten Island, New York, U.S. During a cleaning operation, 42 workers were inside one of the TETCo LNG tanks, which had supposedly been completely drained ten months earlier. However, ignition occurred, causing a plume of combusting gas to rise within the tank. Two workers near the top felt the heat and rushed to the safety of scaffolding outside, while the other 40 workers died as the concrete cap on the tank rose 20–30 feet in the air and then came crashing back down, crushing them to death. October 6, 1979, Lusby, Maryland, US. A pump seal failed at the Cove Point LNG import facility, releasing natural gas vapors (not LNG), which entered an electrical conduit. A worker switched off a circuit breaker, which ignited the gas vapors.