In 1979 3M revamped its technology--sold under the Opticom brand--to allow it to recognize two different priority levels: a high level for emergency vehicles, which could force traffic lights to change immediately and a lower level for transit vehicles, which could hold off changing the light entirely if changing the light to green would snarl traffic.

FORBES: Magazine Article

Network Rail said the level crossing was not deemed as "high risk", as it is on a quiet road with little traffic.

BBC: Level crossing crash: One dead as train hits car