If there is a spill of liquid hydrogen, why will it likely burst into flame spontaneously?

Coal gasification electric power plants are now operating commercially in the United States and in other nations. This technology produces clean-burning hydrogen that can be transferred to customer facilities by pipeline. Hydrogen can also be transported in bulk by highway or rail.

  1. If there is a spill of liquid hydrogen, why will it likely burst into flame spontaneously?
  2. Why do experts recommend the use of a thermal-imaging camera for detecting a hydrogen leak from a pipe fitting connected to a steel cylinder of hydrogen?

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