I saw a short tv report last week showing a test done on a hydrogen powered locomotive. It was done on a test track and worked, albeit a short run? The equipment was all inside a carriage and the next step was to modify it to fit beneath the floor. I don’t know if it was fuel cell based or hydrogen gas based.
A diesel train detailed near us a couple of weeks ago. Ruptured tanks spilled a significant volume. Checks are ongoing on the estuary re pollution. There are worries about the local shellfish industry, fish migration, sludge affecting flora/fauna.
A fire was put out despite difficult access.
If it was hydrogen gas then other than initial fire/explosion risk, leakage would be dispersed by winds. Localised air/hydrogen would be risky but as distance increased less so until none.
Having said that I think hydrogen gas tankers would be designed with added safety, as with current ones transporting dangerous materials. Cryogenic stainless steel, double skin, impact resistant cradles/cages.
