Lads,

AFIAK, from the alarm signal that a train is approaching, a gate must be shut by a gatekeeper 5 minutes before a train approaches same; this window is in order to allow the last traffic clear through the crossing and for the gate keeper to communicate that the gate is free for a train to pass through; 2 minutes being accepted braking time for a train. One minute is allowed for the gate to be closed from start to finish; this leaves a gate keeper with just two minutes leeway in lieu of any issues arising or for a train to arrive earlier.

I have a gatekeeper manual at hand somewhere and will try to confirm the drill; automation will not speed up this operation greatly as of yet.