RAIB – the Rail Accident Investigation Branch – has released its Safety Digest on a near miss between a Virgin train and track workers that took place near Kirtlebridge, Dumfries and Galloway, on 14 November 2019.
The work site was protected by a radio-based Lookout Operated Warning System (LOWS), regularly used on the West Coast main line in southern Scotland because the combination of high train speeds and curved track often precludes use of a warning system relying on lookouts using flags. While the system was in place and had been tested, the remote lookout had not understood that he was now ‘looking out’ – it seems he was waiting for a telephone call from the controller to tell him his duty had started.
The LOWS team consisted of a controller with the equipment at the worksite – the receiver, lights and sirens that would alert the track workers to an approaching train – and two lookouts, one situated 1.8km north of the site of work and the other positioned 2.5km south.
Using the dedicated mobile phones provided with the LOWS equipment, the controller checked in with both north and south lookouts and they satisfactorily tested their transmitters to make sure they activated the warning lights and sirens.
However, the report states that, after checking with the northern lookout, “when the phone call ended the controller was expecting the lookout to send a warning when a train was approaching, but lookout (north) believed this was not yet required”.
So, when a train passed just two minutes later, “the LOWS transmitter is not operated because the LOWS lookout did not believe that he was required to start giving warnings for trains”.
Three members of the inspection team stepped onto the track to start work at about this time.
The train rounded a corner, saw the three workers on the track, sounded the horn and applied the emergency brake. The three workers jumped clear just in time – estimated to be one second before the train passed them.
The RAIB investigation received conflicting evidence about the words spoken during the last telephone conversation. The controller stated that he said “right, that’s you up and running”, while the lookout stated the controller told him he was going to phone the other lookout and thought the controller was then going to phone him back.
All the evidence pointed to the members of the LOWS team following their normal practice of using informal language, rather than the formal communication protocol mandated by Network Rail. Their conversation certainly did not result in a clear understanding between the staff involved.
Concluding its report, RAIB stated that this incident demonstrates the importance of:
- Staff reaching a clear understanding when communicating messages affecting the safety of people on the track;
- Ensuring that safety critical communication protocols are concise and easy to apply by those working on site;
- The need for LOWS lookouts to treat the system as live following a successful test, and to always start giving warnings of trains unless the LOWS controller has specifically instructed them not to.