Drowsy Driving is Impaired Driving

According to the National Sleep Foundation, about half of U.S. adult drivers admit to consistently getting behind the wheel while feeling drowsy. About 20% admit to falling asleep behind the wheel at some point in the past year – with more than 40% admitting this has happened at least once in their driving careers.

These startling figures show how prevalent drowsy driving is. What drivers may not realize is how much drowsy driving puts themselves – and others – at risk. In fact, an estimated 5,000 people died in 2015 in crashes involving drowsy driving, according to a Governors Highway Safety Association report.

Impact of Drowsiness on Driving

Driving while drowsy is similar to driving under influence of alcohol:

• Drivers’ reaction times, awareness of hazards and ability to sustain attention all worsen the drowsier the driver is
• Driving after going more than 20 hours without sleep is the equivalent of driving with a blood-alcohol concentration of 0.08% – the U.S. legal limit
• You are three times more likely to be in a car crash if you are fatigued

A driver might not even know when he or she is fatigued because signs of fatigue are hard to identify. Some people may also experience micro-sleep – short, involuntary periods of inattention. In the 4 or 5 seconds a driver experiences micro-sleep, at highway speed, the vehicle will travel the length of a football field.

Prevalence of Drowsy Driving Crashes

According to the National Highway Traffic Safety Administration, every year about 100,000 police-reported crashes involve drowsy driving. These crashes result in more than 1,550 fatalities and 71,000 injuries. The real number may be much higher, however, as it is difficult to determine whether a driver was drowsy at the time of a crash.

A study by the AAA Foundation for Traffic Safety estimated that 328,000 drowsy driving crashes occur annually. That's more than three times the police-reported number. The same study found that 109,000 of those drowsy driving crashes resulted in an injury and about 6,400 were fatal. The researchers suggest the prevalence of drowsy driving fatalities is more than 350% greater than reported.

Beyond the human toll is the economic one. NHTSA estimates fatigue-related crashes resulting in injury or death cost society $109 billion annually, not including property damage.

Interventions for Drowsy Driving

Drowsy driving affects everyone, but especially those under age 25, who make up an estimated 50% or more of drowsy driving crashes.

That means interventions focusing on this age group – males especially – can help reduce drowsy driving among those vulnerable. One such intervention is for parents to incorporate discussions and rules on drowsy driving while completing their parent-teen driving agreements.

Other ways to reduce drowsy driving include:

• Crash avoidance technologies: New and existing safety technologies, such as drowsiness alert and lane departure warnings, can detect common drowsy driving patterns and warn drivers to stay in their lane or take a break
• University interventions: College students receive less than average sleep, with some estimates at less than six hours a night; education programs aimed at college students may help curb drowsy driving and instill healthier behaviors that can last into adulthood
• Getting more sleep: According to the American Academy of Sleep Medicine and the Sleep Research Society, adults should get seven or more hours of sleep each night
• Medication labels: A 2015 article by Consumer Reports found that side effects warnings are not always clear; new labeling guidelines may help drivers understand when to drive or not drive after taking these medications
• Employers: Workplaces with strong off-the-job safety and health programs can include key information on getting sufficient sleep and refraining from driving drowsy

Key Resources and Drowsy Driving Initiatives

• Drowsy Driving Prevention Week
• U.S. Department of Health and Human Services' Healthy People 2020 Program
• NTSB Most Wanted List of Transportation Safety Improvements: Reduce Fatigue-Related Accidents

Too Tired to Drive?

The following are signs and symptoms of drowsy driving, according to the American Academy of Sleep Medicine:

• Frequent yawning or difficulty keeping your eyes open
• "Nodding off" or having trouble keeping your head up
• Inability to remember driving the last few miles
• Missing road signs or turns
• Difficulty maintaining your speed
• Drifting out of your lane