It’s obvious driving and sleepiness don’t mix. But some new research shows just how much of a threat tired drivers can pose to other road users.
It’s not only nodding off at the wheel that can be dangerous. Tired drivers struggle to anticipate hazards, drive too quickly and aren’t as aware of other road users. They’re all the traits we associate with drink driving. Hardly surprising that statistics show driver fatigue may play its part in up to one in five road crashes.
How was the study carried out?
Car magazine Auto Express had one reporter go without sleep for more than 24 hours. Southampton University researchers then put him through his paces in a simulator and compared his results to a well-rested colleague.
The simulator uses a Land Rover Discovery Sport with a series of screens hooked up to it. The two ‘drivers’ get behind the wheel of the car and drive through a virtual world. Researchers assessed their driving and how their reaction times compared in various situations. These included pedestrians stepping out in the road in front of them and virtual cars cutting them up. They also monitored speed through corners and the smoothness of their driving.
What were the results?
The tired driver struggled to plan ahead and anticipate hazards which meant he was braking more often.
More worryingly, the tired driver drove at an average of 63 per cent faster than the alert tester. He also frequently broke the speed limit.
Senior research fellow in transportation and human factors at Southampton University, Rich McIlroy, analysed the drivers’ performance. He noted that the tired driver’s approach to hazards was sometimes to accelerate and veer around them while his fresher colleague saw them coming, adjusted his speed accordingly and avoided any problems.
The fresher driver didn’t need to brake as much because he could anticipate stopping events better. The tired driver didn’t have the capacity to do this: “In one case, he went slightly off the carriageway to avoid a pedestrian and avoid braking,” said McIlroy.
What tired drivers should do
According to the Royal Society for the Prevention of Accidents, around 40 per cent of sleep-related accidents involved commercial drivers. But it’s not only van, lorry and coach drivers who are at risk. Two thirds of those who fall asleep at the wheel are car drivers. More than four in five (85 per cent) are men and a third are 30 years old or under.
To prevent themselves falling asleep at the wheel, the advice is for drivers to take breaks every two hours. And they should never to drive more than 300 miles in a day. Director of policy and research at road safety charity IAM Roadsmart, Neil Greig added: “When you do take a break, it should be for at least 20 minutes. Have a coffee, have a rest. But you can’t expect to recharge your batteries with a one-hour nap every 24 hours.” Anyone going on a long drive is advised to have a good night’s sleep before.
What if you have a medical condition?
Drivers who suffer from medical conditions that cause excessive sleepiness must inform the Driver Vehicle Licencing Agency (DVLA). This includes moderate or severe sleep apnoea syndrome, narcolepsy, cataplexy or both, or any other medical condition that results in excessive sleepiness.
The authorities take medical conditions like these very seriously. Anyone who doesn’t tell the DVLA and continues to drive can be fined up to £1000 if they’re involved in an accident.