Paul Leach
Head of Human Factors, RSSB
As motorists we’ve all been there: quiet roads late at night with nothing to break up the monotony.
We finish the journey safely though a little tired and think we have coped well with the drive, but has it been as safe as we thought?
The problem is that if we have drifted off for a couple of seconds, having what they call a microsleep, we will be none the wiser.
Train drivers are not immune to this condition, though it is fair to say that thankfully rail accidents caused by microsleeps are few and far between.
But they do happen. Tragically in 2016, an early-morning Tramlink service in Croydon came off the rails after exiting a tunnel at Sandilands, killing seven passenger and injuring 61. The Rail Accident Investigation Branch concluded a possible explanation was that the driver had a loss of awareness after a microsleep, and that this was linked to fatigue.
More recently, in July 2022, a freight train ran into the back of another at Loversall Carr, near Doncaster, fortunately without serious injuries, and most likely due to the driver suffering from fatigue. There was significant infrastructure damage and the line was closed for 26 days.
And in December 2024, a Southern Railways passenger train collided with the buffers at London Bridge at low speed when the driver is thought to have experienced a microsleep. Again, thankfully no injuries.
Everyone in the rail industry is committed to reducing fatigue-related accidents but the reasons behind these are not as straightforward as they might first appear.
There are a range of factors that can lead to fatigue such as the start time or structure of a shift, when breaks are scheduled, proximity to the start or end of rest days or holidays, and of course personal circumstances, such as family issues, quality of sleep, or underlying medical issues such as sleep apnoea. In a nutshell, this comes under one simple but all-important heading: driver health and safety.
But in order to better understand these factors we need information which we don’t yet have. New data about microsleeps could lead to positive occupational health and system safety outcomes.
It may identify areas where support and help are needed, whether these are broad structural changes or the opportunity to have conversations and provide support to individuals.
Trials, led by RSSB, are currently being carried out with some train operators using driver alertness and monitoring technology. This technology detects the occurrence of microsleeps. It not only alerts the driver to keep them safe but also provides valuable data to help uncover the range of factors that lead to microsleeps. These can then be acted on.
It’s early days and the data will need careful examination and discussion among all those involved, but even at this stage it’s clear that new technology, data, and insights aiding driver health provide a potential route to greater safety on the railway. And that’s in everyone’s interest.