Few things are as healthy as a good dose of sleep – except when we’re driving. Then, nodding off becomes a lethal danger, and instantaneously. Emma Latham Jones sat down with road safety expert Veronique Feypell on World Sleep Day 2020 to talk about driver fatigue and why it is underestimated.

ELJ: What exactly is “driver fatigue”?

VF: There are two main types of fatigue from a road safety perspective. For one thing, it is the result of a lack of sleep. Simply put, drivers who are tired because they either haven’t slept enough or haven’t slept well are at risk of fatigue. The second type of fatigue is as a direct result of the task of driving. Perhaps the driver has been driving too long without taking a break. Perhaps they have had a long work day and is already tired when getting in the car. For truck drivers, this second type of fatigue could result from the waiting time during the loading and unloading. These two kinds of fatigue have different causes, but both have same negative effect on the ability to drive a car safely.

ELJ: How does that negative effect manifest itself?

In a number of ways. Loss of vigilance is one. Drivers suffering from fatigue may misperceive the road environment. They may not notice important road signs and warnings; or they may not register the complexity of a traffic situation at an intersection. Fatigue makes it more likely that the driver will overlook other road users, as it negatively affects vision. Tired drivers are much less likely to spot a cyclist in their peripheral vision, or a pedestrian coming out into the road. And since fatigue also reduces reaction time, the result can be fatal. In the extreme case, drivers may feel asleep and completely lose the control of their vehicles.

ELJ: Who is most likely to get drowsy when driving and should take particular care?

One might think that older drivers are particularly susceptible to concentration loss. But in fact young drivers are also very much at risk from fatigue. They have less experience on the road, so even slight fatigue may affect their driving performance. Certain medications can contribute to drowsiness. Also, those driving long distances on motorways are more at risk to fall asleep at the wheel. Fatigue is a main source of fatal crashes on motorways. Driving there can be pretty monotonous, which contributes to the fatigue.

ELJ: How big of a problem is driver fatigue? What do the statistics tell us?

VF: We don’t have a lot of statistics, unfortunately, and the ones we have are not very accurate. If one follows the police statistics, one or two percent of fatal crashes are due to fatigue. But a crash usually involves multiple factors, so the link to fatigue is often not obvious. It’s very difficult for the police officer at the scene to pick up all of this. Hence there is probably significant under-reporting. In-depth investigations put the share of crashes in which fatigue played a role at up to 10 percent.

ELJ: Are there attempts to measure how many drivers experience drowsiness, without there necessarily being a crash?

Some such studies exist, but far too few because it’s not easy. You can measure seat belt use by simply about counting who wears them and who doesn’t. But you can’t sit on the roadside and reliably count who is falling asleep at the wheel. Most studies rely on drivers to report their experience. In the United States, a survey by the National Sleep Foundation found that 60% of adult drivers had experienced fatigue while driving at least once per year. But there have also been some studies with monitoring equipment in cars to evaluate drowsiness. They use cameras that detect how often the driver blinks and also register other movements that are indications of fatigue.

ELJ: Couldn’t such technology also be used to warn drivers when they’re about to fall asleep?

VF: Absolutely, that is something researchers and the car industry are working on. It won’t be very long until new cars will be equipped with sensors that can detect drowsy drivers and then triggers a loud “wake up” message. This sort of driving assistance system might play an important role in enhancing road safety. But then there are also very effective low-tech means. On motorways, rumble strips are very good at waking up drowsy drivers when they drift off their lane.

ELJ: What should drivers do who don’t have hi-tech helpers?

VF: Nobody should take the risk of relying on sensors to keep them awake. Stop for a break when you notice you are getting tired. It’s okay to take a 15-minute nap in your car at a petrol station or on a parking area on the roadside. Many countries recommend a break from driving is recommended every two hours. Freight managers also should be encouraged to provide proper information about the risk of fatigue and how to prevent it to their drivers. And freight companies must of course respect legislation on driving time. A cup of strong coffee make help for a short time, but don’t make the mistake of thinking that it will get you home safely if you have a long drive– it won’t. What you need is enough sleep.

ELJ: Thank you so much for your time on World Sleep Day, Veronique.

Veronique Feypell manages the road safety work of the International Transport Forum. She is currently working on, among other things, on the creation of regional road observatories for Africa and the Asia-Pacific. These will help countries in those regions to collect better crash data and use them to inform more effective road safety measures.

Emma Latham Jones is a Young Associate at the International Transport Forum.

Road safety will also be on the agenda at the International Transport Forum’s 2020 Summit on “Transport Innovation for Sustainable Mobility”, inter alia in a session on Road Safety and Security in The Age of New Mobility.