Hydrogen safety problems

Abstract Consideration of use of hydrogen as a common fuel always raises questions on the matter of safety. The hazardous properties of hydrogen should not disqualify it for widespread use. Hydrogen has been used as a transmissible fuel for 150 yr (mixed with carbon monoxide in water gas) and as a portable fuel in cryogenic form within this generation. The accident experience with hydrogen, other than its use in lighter-than-air craft, has not been inordinately worse than the accident experience with more commonly used fuels. Hydrogen has unique properties which require special treatment to lessen risk: broad combustible range, low energy for ignition, rapid diffusion rate and, as a cryogen, the capability to create high pressures if confined without available relief, and the ability to condense all other gases except helium.