LNG Spill

A liquefied natural gas (LNG) spill can happen during an accident or an intentional act such as terrorism. LNG is normally stored and transported in liquid form at a temperature of approximately -161 degrees Celsius. If this supercooled liquid is released from a storage facility, pipeline, or LNG transport ship it begins to warm. As LNG warms above its storage temperature the liquid begins to vaporize. The resulting gas produced by this warming is typically methane, which is the major component (with some ethane) of natural gas. If a spill occurs and the vapor does not ignite, it would build to higher concentrations. At higher concentrations, the vaporized methane will cause an asphyxiation hazard to anyone exposed. If a spill or leak followed by a vaporization event were to occur in a marine environment, the water can facilitate the vaporization process and increase vapor concentration. According to the 2004 Sandia report this is of special concern to ship and pilot-boat crews, emergency response personnel, or others who are exposed. During a spill, LNG vapor concentrations will reach a level where explosion and fire are a likely outcome. As the methane concentration reaches the right level in proximity to an ignition source, an explosion will occur.