You haven’t had a drink all day, so why are the cops pulling you over? They measure your eye movements and declare that you’re sleep deprived. They take away your car keys for 24 hours. That scenario is pure fiction, maybe even a little Orwellian. Nonetheless, an alarming 1 in 5 Canadians admitted that they nodded off or fell asleep at the wheel at least once during the 12 month period prior to being surveyed. The evidence suggests that when we drive sleep-deprived we can be as dangerous as a drunk driver.
How serious is driver fatigue? And should you be concerned about it?
Studies in Canada, Britain and the U.S. all point to the increased risks that drowsy or sleep-deprived drivers create for themselves and others. It’s common sense that fatigue decreases our level of awareness, impairs our judgement and slows our reaction time. Yet, the majority of us don’t give it a second thought—we drive when over-tired or even sleepy.
No big deal? The evidence suggests otherwise. The following statistics should be a wake-up call for all drivers.
- An alarming 20% of Canadians (4.1 million) indicated that they nodded off or fell asleep at the wheel at least once over the previous 12 months.
- Sleep deprivation increased the risk of inappropriate line crossing by 8.1 times.
- Fatigue was considered to be a factor in almost 18% of all fatal collisions and 26.5% of collisions causing injury during the period of 2000 – 2004. According to this statistical model, this represents some 400 deaths of Canadians every year where fatigue played a significant role.
- Sleep-deprived subjects became most affected after 17-19 hours of wakefulness and showed performance similar to those drivers with a blood alcohol content (BAC) of 0.05%.
Who are particularly at risk for driver fatigue?
Accident data indicates that the most frequent drowsy drivers include those who:
- Have varied work hours
- Insist on driving through the night or drive long distances without breaks
- Take medication (or alcohol), which causes drowsiness
- Drive alone, or are high-mileage drivers
- Suffer from sleep disorders
How do I know that I’m fatigued while driving, or if I’m a passenger, that the driver is sleep impaired?
Here are some obvious signs:
- Confused behaviour
- Restlessness, fidgeting
- Tailgating, driving onto raised pavement markers or rumble strips
- Jerking neck, frequent yawning, shallow breathing
- Reduced eye blinking
What can you do to keep awake?
Choose Your Time of Travel. Avoid driving between midnight and 6:00 a.m. This is the peak time for fatigue-related crashes. If at all possible, don’t start a long drive after a full day’s work.
Avoid Alcohol. Avoid alcohol 24 hours before a long trip or at least the night before, as well as during your trip. Alcohol disrupts your sleep and it stays in the body for several hours, making you sleepier.
Check Your Medicines. Check any medications you may be taking (prescription and non-prescription), to see whether any of them can cause drowsiness. If they do, check with your doctor or pharmacist about a non-drowsy alternative.
Get Adequate Sleep Before a Trip. If you stay up late packing your bags and caring for other last minute details, you will be sleep deprived, with an increased risk of driver fatigue. Plan your trip and try pack in advance to allow yourself a full night’s sleep. Or, plan for an overnight stop part way through your trip. When neither of these options are possible, at the first signs of driver fatigue, stop for a power nap.
Share the Driving. This is particularly important for longer trips. If you are the only driver, do not try to complete long journeys non-stop.
Take Regular Breaks. When traveling for more than a few hours, take a break at least once every two hours. If you are feeling drowsy, stop and have a power nap. Power naps (15-20 minutes) are a proven way to improve alertness even when one is sleep deprived. Remember, though that you may be groggy for about 15 minutes once you wake up, if your nap is longer than 20 minutes. Also, try exercising vigorously during your break, which will increase your heart rate and circulation and in turn improve your alertness.
Try Caffeine: Even in low doses, caffeinated drinks can improve your alertness when drowsy. Some studies indicate that it takes two strong cups of coffee (over 150 ml of caffeine) to work. Even at that, it can take up to 30 minutes before it has any effect. Note however, that although coffee can help you stay alert if you are sleep deprived and/or drowsy; it is not a substitute for sleep.
Traffic Injury Research Foundation, (2004) Road Safety Monitor: Drowsy Driving
Philip et al., (2005) Fatigue, sleep restriction and driving performance, Accident Analysis and Prevention, Vol. 27 37, pp. 473 -478.
Elzohairy, Yoassry; Senior Advisor, Ministry of Transportation, Fatal and Injury Fatigue-Related Crashes on Ontario’s Roads: A 5-year Review, 2008
Williamson, Ann, M., et al. Developing measures of fatigue using an alcohol comparison to validate the effects of fatigue on performance, Accident Analysis and Prevention 33 (2001) 313-326. 8