Nighttime and Drowsy Driving

The single biggest risk factor

Fifty-six percent of teen crash deaths occur between 6pm and 6am¹. As reported by a 2010 study by Texas A&M Transportation Institute, this is primarily due to a combination of the visibility challenges caused by dark conditions, slower response time brought about by fatigue, and a lack of experience driving under such conditions. It is largely for these reasons that most states include a nighttime driving restriction in Graduated Driver License (GDL) laws. In most states with a GDL law, the nighttime restriction and a limit on the number of passengers allowed are the most widely implemented features of that law.

The problem of visibility:

• 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 hazards².
• High Intensity lights are becoming more common. These lights are brighter to on-coming traffic and require your eyes to adjust faster³.
• 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 darkness⁴.
• 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 areas⁵.
• 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 am⁶.

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 down³.
• 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 vehicle³.
• Keep your headlights and windshield clean. A thin film of debris on your headlights can reduce your visibility significantly².
• 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 guide³.
• Have your headlights properly aimed. Misaimed headlights blind other drivers and reduce your ability to see the road³.

The problem of drowsy driving:

• Research suggests that teens should have 8 to 10 hours of sleep each night. Most teens do not get enough sleep — one study found that only 15% reported sleeping 8 1/2 hours on school nights⁶.
• Being awake for 18 hours is similar to having a blood alcohol concentration of .05 and .10 after 24 hrs. .08 is legally intoxicated for adults over 21⁶.
• Young drivers have a higher risk of falling asleep behind the wheel⁶.
• Sleepiness or fatigue causes the following⁷:
  • Impaired reaction time, judgment, and vision
  • Problems with information processing and short-term memory
  • Decreased performance, vigilance, and motivation
  • Increased moodiness and aggressive behaviors
• 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 vehicle⁸.
• A recent 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 night⁹.
  • 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 over¹⁰:
  • 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 are¹⁰:
  • Sleep-deprived or fatigued (6 hours 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
  • Taking medications that make you tired (cold tablets, antihistamines)
  • 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 driving¹⁰:

    • Get a good night’s sleep before you hit the road. You’ll want to be alert for the drive, so be sure to get adequate sleep the night before you go
    • 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. Just as you should not swim alone, avoid driving alone for long distances. 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 run
    • Take a nap—find a safe place to take a 15 to 20-minute nap, if you think you might fall asleep. Be cautious about excessive drowsiness after waking up
    • Avoid alcohol and medications that cause drowsiness as a side-effect
    • Avoid driving at times when you would normally be asleep
    • Consume caffeine. The equivalent of two cups of coffee can increase alertness for several hours

Sources:

1. Insurance Institute for Highway Safety, 2015

2. Texas A&M Transportation Institute

3. AAA Foundation

4. National Safety Council

5. 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

6. National highway traffic safety, Query of FARS database

7. National Sleep Foundation

8. National Sleep Foundation: https://sleepfoundation.org/sleep-news/expert-consensus-panel-concludes-missing-night-sleep-renders-drivers-unfit

9. 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

10. DrowsyDriving.org