Analysis has shown that liquid hydrogen can be significantly safer than liquid methane and synjet, the other alternative fuels for aircraft. With LH2 there will be less risk of a major spill occurring in the event of a crash in which passengers can survive the impact. If fuel is spilled, and assuming ignition does not occur, LH2 will not spread as far before it vaporizes, becomes buoyant, and dissipates in the atmosphere. If the spilled fuel is ignited, as will occur more than 80% of the time with any of the fuels, the resulting hydrogen fire will be of such short duration and will be confined to such a small area that the passenger survival rate can be expected to be much higher.