Are there any specific considerations, hazards or safety barriers that are applicable to the operation of hydrogen trains?

Hydrogen has been used as a fuel to operate cars, buses, trucks, submarines, aircraft, forklifts, trains and virtually every type of mobile equipment. Each has special considerations which often drive specific requirements for that vehicle type. For example, higher g-loadings of rail operations and operations within tunnels are a couple considerations, but there are no significant barriers that would prevent the application of hydrogen for trains for a properly designed system.