Research, commissioned and funded by online bed retailer, Time4Sleep.co.uk, was conducted to raise awareness around the safety issues of driving whilst tired – in particular those travelling for work. The experiment took place at the UK’s Transport Research Laboratory (TRL) with a set of triplets has revealed how dangerous it is to drive whilst tired, highlighting the problems surrounding UK workers.

To ensure the experiment was as fair as possible, a set of male triplets, aged 27 from Essex was sourced. Robert Davis (Assistant Manager in Retail), Steven Davis (Kitchen Designer) and Patrick Davis (Trade Customer Advisor).  

The night before
The experiment involved the triplets having differing levels of sleep. After picking straws, Robert chose the longest, which meant he had the luxury of a full night’s (normal) sleep, whereas Steven picked the mid-length straw, meaning he had a night of disrupted sleep thanks to a lifelike robotic baby. This was to mimic the sleeping patterns of a parent with a young child, who will often have to get up and drive to work the next day. Finally, Patrick selected the shortest straw meaning he was awake all night, to demonstrate the full effect of sleep deprivation on driving and to highlight the dangers of those that work at night and then drive home the next day. To record the experiment and to check Patrick didn’t fall asleep, he was asked to make a video diary every hour and send a text to one of the researchers every half an hour. GoPro cameras were also set up throughout the house to keep track of the triplets’ movements. To watch the full video of the experiment please click here: www.time4sleep.co.uk/dont-drive-tired  

The driving test
The next day the triplets each drove the same driving simulator at TRL, a provider of independent and impartial research, consultancy, testing and certification for all aspects of transport. This was a 90 minute drive in a real car surrounded by projections of a motorway, ensuring the experience was as true to real life as possible. Each drove whilst wearing a heart rate monitor which gave alerts when their heart rate dropped to a level classified as fatigued, observed by principal psychologist, Simon Tong, from the control room next door. 

Each triplet was asked to stick to the inside lane of the three-lane motorway and drive at a constant speed of 60mph. Every five minutes they were asked to rate their own level of sleepiness, with 1 being ‘very alert’ and 9 being ‘very sleepy’. Throughout the drive they were also asked to flash their headlights whenever a red bar appeared above the motorway, for the scientists to monitor their reaction times. The driving simulator recorded driver and vehicle movements throughout each drive so that there was a detailed record of speed, acceleration and lane keeping.  

Results
The results of the drives were shocking and revealed even disrupted sleep can have a huge impact on driving ability. Robert, who had a full night’s sleep had no fatigue alerts from the heart rate monitor and had the fewest lane departures (30 departures and a total of 39 seconds out of his lane) compared to Steven who had 4 fatigue alerts and left his lane a total of 58 times for a duration of 1 minute and 40 seconds. Patrick not only received 12 fatigue alerts but his ability to stay in the same lane was severely reduced, with 188 separate lane departures, equivalent to 6 minutes and 26 seconds travelling out of his lane.  

Summary of Time4Sleep.co.uk’s main results: 

Interestingly, it was Steven with disrupted sleep who had the slowest reaction times, which highlights that even people who have managed to have some sleep are still putting themselves and others at risk by driving – a common issue for workers with young children, or those that are travelling early in the morning after a lack of sleep. 

He failed to react ten times, which was twice as often as Patrick and substantially more than Robert, who had no missed reactions.  

A look at UK drivers
Time4Sleep.co.uk also commissioned a survey of 1000 UK drivers to support the experiment. The data discovered that over three quarters of drivers (83 percent) have driven tired with 1 in 10 confessing to doing it regularly.  

When looking at the main reasons why people have risked driving whilst tired, work related motives take up three of the top five:
1. On a long distance journey whilst travelling for pleasure (27 percent)
2. Going to work in the morning after lack of sleep (24 percent)
3. Driving home after a night shift at work (22 percent)
4. Driving home after a work trip (12 percent)
5. Taking a child to nursery (10 percent) 

Of those asked, 1 in 4 (23 percent) would be willing to drive for 30 – 60 minutes whilst feeling tired, which could involve driving on a motorway. Shockingly, a third of people (33 percent) admitted to feeling like they had put people at risk in the past whilst driving tired with 23 percent saying they didn’t feel in control and 19 percent saying they felt they would fall asleep at the wheel. A further 19 percent said they felt they had been in danger of causing an accident and a quarter (25 percent) revealed they felt their reactions were slower and they shouldn’t be driving. When it comes to being a passenger, 55 percent of respondents also said they had been a passenger of a tired driver in the past. 28 percent of those said they had been scared for their safety and a further 20 percent felt they were going to crash. Worryingly 19 percent also said they didn’t feel comfortable asking the driver to stop. 

Jonathan Warren, Director at Time4Sleep.co.uk who commissioned the research, said: “As a bed and mattresses retailer, we know sleep is very important and affects our health and wellbeing. What we found is that a lot of UK workers are putting themselves at risk, with the main reasons for getting behind the wheel when tired being for work related purposes. “We hope our research and video will encourage drivers to think twice before getting behind the wheel after experiencing lack of sleep, and UK companies will consider how best to ensure their employees are safe when driving for business.” 

What the experts say
Simon Tong, principal psychologist at TRL, commented on the findings: “The findings of our experiment reveal just how important it is to only undertake driving when feeling alert and having had sufficient sleep. The key finding here was how affected Steven was with disrupted sleep as this is most common to real life. “One dangerous aspect of fatigue is how it can come and go quite suddenly. You can get a false impression that you’ve overcome it, only to find that it strikes again a short time later when you perhaps aren’t expecting it. This was clearly seen when we observed Steven doing his drive. 

“Robert’s drive was near perfect, which is to be expected of someone who has had 7-8 hours sleep as Robert did the night before. However, Patrick was driving on a different level, with terribly slow responses, imprecise motor skills and a self-confessed lack of control. He was unable to stick to a lane or speed and his driving performance was akin to being drunk, if not worse.” Iain Temperton, Director of Communications for Road Safety GB, added: “We commend Time4Sleep.co.uk for investing the time and effort to highlight this very important issue. As you hear in the video, one in five road crashes are attributed to fatigue, which makes it a significant factor when considering the safety of our road network. “Many of us have experienced disturbed nights looking after children and many of us have also driven the following day. Driving or riding a vehicle is a responsibility; this video clearly shows us that doing so on reduced levels of sleep increases the likelihood of death or injury. I would urge all drivers to watch this video and would like to thank Time4Sleep.co.uk for producing it.”