A trade union boss has branded the ScotRail train which decoupled and abandoned rush hour passengers as the “most serious railway incident in recent years”.
An investigation is still ongoing as to how Monday’s train separated at Uphall and sped off, leaving commuters in the back three carriages behind.
The incident comes two years after a £19 million upgrade to all 40 of the Class 334 three-car electric units which included the installation of new heated couplers to increase the number of six car trains able to run the network and reduce defects.
The improvements were introduced to “increase the speed at which train units can be linked and separated, improving turnaround times to match the number of carriages to passenger demand more effectively”.
But an anonymous train driver told the Evening News: “This is a concern for all drivers in ScotRail, safety of us and travelling public. Apparently he [the driver] no indication that the units had uncoupled.”
People on board the stranded carriages of the 5.20pm service from Waverley to Helensburgh Central were forced to activate the emergency release to open the doors as fears grew regarding other inbound trains to the platform.
Meanwhile, customers on board the front three carriages continued on their journey a further two stops to Bathgate, where the service terminated.
Safety fears have been raised by rail experts and passengers alike with an expectation that the emergency brakes should have activated on the train when the carriages divided.
Kevin Lindsay, the Scottish organiser of the Associated Society of Locomotive Engineers and Firemen, said: “This is the most serious railway incident in recent years. This is how seriously we are taking it. It is a highly unusual case and in all my time I have not come across another similar incident in the UK.
“100 per cent the train’s brakes should have activated and it is a concern that the safety system in place has not worked. The last thing we want is an unsafe railway. We need to get to the bottom of this as safety for us paramount.”
Passengers were left frustrated at being left in limbo for half an hour until British Transport Police and an engineer arrived.
The Rail Accident Investigation Branch has conducted initial enquiries into the incident.
A ScotRail spokesman said: “We are working hard to find out the cause.”