Reduced visibility combined with sleep deprivation make driving at night dangerous
DID YOU KNOW…
Sleepiness and irregular sleep schedules have many unintended consequences, one of which is to negatively impact learning, memory, and performance (1).
Men are more likely to fall asleep while driving than women (1).
The dangerous combination of sleep loss and alcohol could impair driving performance even in students who are not legally intoxicated (1).
The problem of drowsy driving:
- Drowsy driving and impaired driving have similar effects (2,3) . Both cause:
- Problems with information processing and short-term memory
- Increased moodiness and aggressive behaviors
- Decreased performance, vigilance, and motivation
- Impaired reaction time, judgment, and vision
- Young drivers have a higher risk of falling asleep behind the wheel (3).
- A recent study (2015) found that individuals who have slept less than 2 hours in the prior 24 hours are too sleep deprived to get behind the wheel of a vehicle (4).
- A survey found that teens report being “reluctant to miss out” and have an “always-on lifestyle” that can contribute to drowsy driving as they are getting less than six hours of sleep each night (5).
- 70% of teens surveyed admitted to driving tired
- 50% reported actually falling asleep or nearly falling asleep at the wheel citing:
- A busy schedule: 43%
- Staying up late to do homework: 32%
- Staying up late for social activities: 24%
- Working late hours during the week: 20%
- Being tired or hung over from drinking/partying the night before: 10%
What to do about drowsy driving:
- Here are some signs of being tired and it’s time to pull over (6):
- Difficulty focusing, frequent blinking and/or heavy eyelids
- Difficulty keeping daydreams at bay
- Trouble keeping your head up
- Drifting from your lane, swerving, tailgating and/or hitting rumble strips
- Inability to clearly remember the last few miles driven
- Missing exits or traffic signs
- Yawning repeatedly
- Feeling restless, irritable, or aggressive
- Before you drive, consider whether you are (6):
- Sleep-deprived or fatigues (6 hrs of sleep or less triples your risk)
- Suffering from sleep loss (insomnia) or poor quality sleep
- Driving long distances without proper rest breaks
- Driving through the night or when you would normally be asleep
- Studying a lot or attending more activities than usual, which may be decreasing your sleep time
- Drinking even small amounts of alcohol
- Driving alone or on a long, rural dark or boring road
- What you can do to prevent falling asleep while driving (6):
- Get a good night’s sleep before you hit the road.
- Don’t be too rushed to arrive at your destination. Many drivers try to maximize the holiday weekend by driving at night or without stopping for breaks
- It’s better to allow the time to drive alert and arrive alive
- Use the buddy system. A buddy who remains awake for the journey can take a turn behind the wheel and help identify the warning signs of fatigue
- Take a break every 100 miles or 2 hours. Do something to refresh yourself like getting a snack, switching drivers or going for a jog
- Take a nap. Find a safe place to take a 15-20 minute nap if you think you might fall asleep. Be cautious about excessive drowsiness after waking up.
- Avoid alcohol and medications that may cause drowsiness as a side-effect
- Consume caffeine. The equivalent of two cups of coffee can increase alertness for several hours.
The problem of visibility at night:
- The average person’s field of vision is smaller without the aid of light, and glare from oncoming headlights can further limit the ability to see clearly and avoid hazards (7).
- High Intensity lights are becoming more common. These lights are brighter to on-coming traffic and require your eyes to adjust faster (7).
- It is more difficult to judge other vehicle’s speeds and distances at night.
- Dusk is the most dangerous time since your eyes are constantly having to adjust to more darkness (8).
- Rural roadways can be especially dangerous at night due to higher numbers of unlit roadways. In 2015, the number of people who died in a fatal crash was 2.6 times higher in rural areas than in urban areas (9).
- On average, 62% of fatal teen crashes occurred on rural roadways and an average of 53% of the fatal crashes occurred between 6 pm – 6 am (10).
What to do about poor visibility:
- As always, wear your seat belt. The danger of driving at night should not be multiplied by being unsecured.
- Keep distractions to a minimum to keep your eyes and attention on the road.
- Turn headlights on at dusk and observe night driving safety as soon as the sun goes down (11).
- Reduce your speed and increase your following distances. Don’t overdrive your headlights. You should be able to stop inside the illuminated area. If you can’t, you are creating a blind crash area in front of your vehicle (11).
- Keep your headlights and windshield clean. A thin film of debris on your headlights can reduce your visibility significantly (11).
- If an oncoming vehicle’s lights are too high, avoid glare by watching the right edge of the road and using it as a steering guide (11).
- Have your headlights properly aimed. Misaimed headlights blind other drivers and reduce your ability to see the road (11).
Sources:
- D. Hershner, and Chervin R.D. Causes and Consequences of Sleepiness Among College Students. Nature and Science of Sleep. 2014.
- Jackson ML, Croft RJ, Kennedy GA, Owens K, Howard ME. Cognitive components of simulated driving performance: sleep loss effects and predictors. Accid Anal Prev.2012;50:438.
- National Sleep Foundation
- National Sleep Foundation: https://sleepfoundation.org/sleep-news/expert-consensus-panel-concludes-missing-night-sleep-renders-drivers-unfit
- Liberty Mutual & SADD: https://www.libertymutualgroup.com/about-lm/news/news-release-archive/articles/new-study-finds-teens-fear-of-missing-out-is-proving-to-be-dangerous
- DrowsyDriving.org
- Texas A&M Transportation Institute
- National Safety Council
- National Highway Traffic Safety, Rural/Urban Comparison of Traffic Fatalities, Traffic Safety Facts, 2015 data, DOT HS 812 393 https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/812393
- National highway traffic safety, Query of FARS database
- AAA Foundation