CHENNAI: Passengers travelling on trains that pass through non-interlocked level crossing (LC) gates, as well as road users crossing the gates, face potential safety risks as the Southern Railway (SR) has no mechanism to detect or prevent human error at these gates. In particular, there is no safeguard if a gatekeeper at a non-interlocked LC fails to close the gate or reopens it prematurely before the train has passed.
SR operates 1,602 level crossing gates along its 7,761-km network. Of these, 1,365 gates are integrated with interlocked signalling systems, while the rest 237 gates are manually operated.
An interlocked LC gate is connected to the signalling system at a nearby station cabin. When a gate needs to be closed for a train to pass, the Assistant Station Master (ASM) or Station Master (SM) alerts the gatekeeper, who then lowers the barriers and removes a key from the LC locking device.
This key is inserted into the signalling equipment hut (relay room), which energises a relay and sends an indication to the station control panel. Only after receiving this confirmation can the SM or ASM set the route for the train. Once the route is set, the key gets locked, preventing the gatekeeper from removing it until the train has passed.
After the train crosses the LC, the SM releases the route by pressing buttons in his cabin, unlocking the key in the relay hut. The gatekeeper then retrieves the key, replaces it in the LC equipment, and opens the gate.
“If the gatekeeper becomes incapacitated, fails to act, or falsely claims the gate is closed, the SM will see the actual gate status on the control panel and will not clear the train for movement. The station master cannot manually bypass the system to clear the signal to ‘green’ if the level crossing gate remains open,” said a railway official.
In contrast, non-interlocked gates operate solely on verbal communication. The SM or ASM contacts the gatekeeper over railway phone to instruct them to close the gate when a train approaches. “If the gatekeeper falsely claims the gate is closed without closing it, the SM has no way of verifying the gate’s status,” the official added. Such a lapse occurred at Semmankuppam, when the SM was allegedly informed the gates were closed, but they were not.