Made me Smile.................

Would that really stop a train or tram from severing the hose?  Could it derail the vehicle?  

You got it all wrong:they were waiting for a car travelling on the rails with tyres.

Dungassin posted:

Would that really stop a train or tram from severing the hose?  Could it derail the vehicle?  

Try as I might, I can't begin to imagine how their minds were working !

Probably just 'following the manual' without any thought of what their actions might actually cause.   The logical thing to do would be to contact the train company (assuming it's a railway line) and ask them to suspend services for a short time.

Phototshop maybe?