U.S. Department of Energy - Energy Efficiency and Renewable Energy
Fuel Cell Technologies Office – Safety, Codes & Standards
Hydrogen-Fueled Vehicle Safety Systems Animation (Text Version)
Hydrogen fueled vehicles have multiple safety systems that detect and prevent the accidental release of hydrogen. There are sensors that detect leaks, a computer that monitors fuel flow, and an excess flow shut-off valve. Hydrogen tanks also have a pressure release device, much like those on natural gas water heaters in our homes. If a leak is detected, the flow of fuel is shut off so the amount that leaks would be small and most likely vent harmlessly into the air.