Drowsy driving is a major problem. The Governor’s Highway Safety Association estimates that the annual cost of automobile accidents related to sleep issues and drowsiness is $109 billion., While distracted driving gets most of the public’s attention, there is very limited understanding of what drowsy driving is, what the warning signs are, and how to prevent it.
Drowsy driving is the operation of a motor vehicle while being impaired by sleep deprivation. Drowsy driving does not only include falling asleep at the wheel; it also includes slower reaction times, shorter attention span, and impaired judgment and decision making.
Studies about drowsy driving have had some surprising (and scary!) results. For example, the Centers for Disease Control and Prevention (CDC) found that an estimated 1 in 25 adult drivers (aged 18 years or older) reported having fallen asleep while driving in the previous 30 days.,, In 2015, the AAA Foundation found that almost one third (32%) of all drivers admitted to driving within the past 30 days when they were so tired that they had trouble keeping their eyes open.
Drowsy Driving Estimates
It is difficult to identify instances where drowsiness contributed to accidents, because there is usually no way to test for drowsy driving after an accident occurred. As a result, statistics vary widely. The National Highway Traffic Administration estimated that drowsy driving caused over 72,000 crashes, 44,000 injuries, and over 800 deaths in 2013. In contrast, the Governors Highway Safety Association (GHSA) released a report in August 2016 that estimated that drowsy driving causes an average of 328,000 annual crashes, 109,000 injuries, and 6,400 deaths on U.S. roadways.
While most current national and state-wide database estimates place fatigue-related crashes at approximately 2-4% of total crashes, estimates from some states suggest a higher percentage. One recent Virginia Tech study of Washington, DC and Virginia drivers found that fatigue was a factor in 12% of all crashes and 10% of all near-crashes observed in their study. The Texas Department of Transportation captures fatigued or asleep as a contributing factor on its crash reporting form. From 2013 through 2015 in Texas, there were 27,996 crashes attributed to a drowsy driver.
Characteristics of Vehicle Crashes
Despite the difficulty in establishing that drowsy driving contributed to an accident, certain crash characteristics indicate that drowsy driving was a factor: no skid marks, the accident happened late at night/very early morning (approximately midnight-6am) or in the mid-afternoon (approximately 1pm to 4pm), or a single person was in the car, and/or the accident occurred on a relatively narrow straight road such as a two-lane highway, long country roads, or suburban roads. In a National Highway Traffic Safety Administration survey using state data, 60% of the 4,010 respondents admitted to falling asleep while driving on an interstate-type highway with posted speeds of 55 MPH or higher and nearly half of the respondents reported nodding off between 1pm and 4pm and 9pm and 6am., The National Highway traffic survey also found that 0.7% of drivers have been involved in a crash in which drowsy driving was the main factor. This amounts to an estimated 800,000 to 1.88 million drivers a year when compared to all US drivers.
Tips for Avoiding Drowsy Driving
Sleep-deprived drivers: The National Sleep Foundation recommends 7-8 hours of sleep per night or at least a 30 minute nap right before driving.
Young or new drivers: According to the National Sleep Foundation, sleep-related crashes are most common in younger workers such as ambulance drivers and truck drivers.
Shift workers: Individuals who work early morning/late night shifts and extended hours
People who drive long hours: This includes long-haul truck drivers and drivers such as truck drivers, bus drivers, cab drivers including UBER, & delivery drivers
People with sleep disorders: Those who are untreated are at increased risk
Drivers who take medication: Prescribed and over-the-counter drugs can induce sleep
Travelers: Individuals who change time zones frequently such as airline pilots, stewards, stewardesses, flight crews, and frequent business travelers
Drowsiness is a growing health problem in the police force, too. Researchers from Harvard found that 46% of police officers reported drowsy driving and even falling asleep. A quarter of these officers said that drowsy driving happened one to two times a month, and about 40% of the officers in the study screened positive for sleep disorders. That is nearly double the rate of the general population.
It is important to be able to recognize signs that you may be too drowsy to drive in order to keep yourself and others safe. For example, you should take precautions if you are yawning repeatedly, you have difficulty focusing and keeping your eyes open. Other warning signs might include: disconnected thoughts; difficulties with recall; trouble reading signs and/or following directions; and swerving in and out of your driving lane. Drowsy driving symptoms often mimic symptoms of drunk driving.
Other Causes of Drowsy Driving
Sleep problems include “microsleeps,” which are periods of time in which individuals lose the ability to pay attention to their surroundings. Also included are effects of sleeping aids or sleep apnea. Between 50-70 million Americans have a sleeping disorder that could affect their driving skills.,
Sleep apnea is a common disorder in which a person has difficulties breathing during sleep. Obstructive Sleep Apnea (OSA) is the most common medical disorder that affects driving during the daytime. OSA can greatly disturb sleep, so that even if individuals have slept for 8 hours, they will not feel rested and are more likely to be impaired, resulting in higher traffic accident rates.
The best way to make sure your mind and body are in optimal shape for driving is to plan ahead and get 7-8 hours of sleep before you drive. However, avoid sleeping pills the night before you drive because they rarely increase sleeping enough to make for sleepiness caused the next morning while the sleeping pill is still in your body. For example, Belsomra stays in the body for more than 12 hours.
Other tips include:
- Drive with someone else in the car so you can switch drivers if you become drowsy.
- Use public transportation or car pool.
- When driving more than 100 miles or over two hours, schedule a break.
- Avoid driving very late at night or early in the morning.
- If you feel sleepy, pull over and rest for at least thirty minutes.
In addition, drinking a caffeinated beverage can help you to avoid drowsy driving symptoms. However, caffeine will take about 30 minutes to kick in and can be less effective if you drink a lot of caffeine on a daily basis. Caffeine and a nap will help improve your function more than just a nap or the caffeine alone.
Be aware that opening the window, eating, having a conversation, turning on the heater/air conditioner, or using car functions such as turning on lights, using chair massage functions/devices, or playing loud music will not help you become less drowsy.
In general, being overweight is associated with drowsy driving. Avoid eating starchy foods or drinking alcohol right before and during your drive. Be aware that roads with many rest stops, well-defined lanes, and rumble strips are less likely to have drowsy driving accidents compared to other roads such as country roads.
Working to Solve the Problem
According to the national database in the United Kingdom, drowsy driving is involved in about 4% of all road crashes. However, these figures are believed to be a very significantly under-estimation because fatigue is hard to spot; unlike alcohol and drugs, police can’t test for tiredness. According to a national survey drowsiness contributed to one in five fatal automobile crashes in the UK.
In 2008, the UK started a national campaign entitled THINK!, which is run by the Department of Transportation to increase awareness of drowsy driving issues through ads, online videos, posters, and driver’s education classes. State governments in the United States have looked at this project as a possible model. The project reports great results in preventing and educating drivers about drowsy driving; however no data to support the drowsy driving claims is publicly available on the Internet.
New York State started The New York State Partnership Against Drowsy Driving, a coalition that teaches officers to be on the lookout for erratically driven large trucks/buses, which might indicate signs of distraction, alcohol or drug impairment, and/or drowsy driving. Officers are instructed to advise operators to stop driving when these signs are present. In addition, the coalition implemented later school start times and drowsy driving education has been added to drivers’ education classes.
In Utah, a state-wide study concluded that two strategies helped to reduce the incidence of motor vehicle crashes by 63%: 1) highway signs reminding motorists that drowsy driving causes crashes and 2) encouraging drowsy drivers to pull over if necessary through use of PSAS and highway signs. The Iowa Department of Transportation now includes reminders about the dangers of driving drowsy on its 80 unique message signs located on highways across the state. The state’s goal is to start a public conversation about drowsy driving.
In 2016, Texas and Florida have started similar plans to report drowsy driving as a cause of accidents, to increase drowsy driving education through driver’s education classes, later school start times, and law enforcement training.
The National Highway Traffic Safety Administration (NHTSA) created a Drowsy Driving Research and Program Plan in 2016. The plan addresses the six key areas of focus for the United States: 1) measurement and problem identification, 2) public awareness and education, 3) policy development, 4) high-risk population monitoring, 5) vehicle technology, and 6) infrastructure updates.
NHTSA projects include plans to train police on how to ask about drowsy driving during a traffic stop, place new highway signs, and to examine certain state laws. NHTSA will develop guidelines addressing both distracted and drowsy driving as well as evidence-based awareness and educational materials (public service announcements, online videos, and new driver education materials on drowsy driving) similar to those adopted to reduce driving without seat belts.
The NHTSA, the National Sleep Foundation, The Governors Highway Safety Association, and AAA recommend organizational policy changes to control and reduce drowsy driving accidents:
- Incorporate drowsy driver prevention issues into policies that affect young drivers (nighttime driving restrictions, later school start times, tools to help high schools, colleges and universities educate their students)
- Incorporate drowsy driver prevention issues into workplace policies (trucking hours of service, ambulance and bus drivers hours of service, taxi polices on work hours, hospital policies on work hours, and police agency policies on hours worked)
- Educate drivers: through new drivers education classes, work place posters and public service announcements, and as part of renewing licenses
- Educate law enforcement: identify symptoms and signs of a drowsy driver by looking for erratic drivers and signs of sleepiness, such as droopy eye lids or no signs of breaking (no skid marks)
- Initiate state drowsy driving campaigns
Current Drowsy Driving Laws
Trucking Industry Regulations
In 2015, a short report entitled Regulating Danger on the Highways: Hours of Service Regulations, found that the commercial truck driver hours of service provisions in the United States, Canada, and the European Union permit drivers to work as many as 14 hours. Australian permit drivers can work as many as 12 hours. Current hours of service regulations governing commercial truck drivers in the United States leave gaps that could permit drivers to work long hours on a regular basis and allow drivers to drive after no sleep for 24 hours.
Current federal regulations require that within a 24-hour period, a truck driver may drive for no more than 11 hours and may work for 3 additional hours on work-related tasks that do not involve driving. A truck driver may not drive after 60 hours on duty during 7 consecutive days or 70 hours on duty during 8 consecutive days. A driver may not begin a new 7- or 8-day consecutive period until he or she takes 34 or more consecutive hours off duty.,
Here is a comparison of the rule that was in place from 2003 to 2015 and the rule in place as of December 20th 2016:
34-Hour Restart Rule
|34-Hour Rule (Prior to 2016)||34-Hour New Rule (Since 2016)|
|Driver’s 34-hour restart must include two periods between 1AM to 5AM||34 hour restart no longer requires two periods between 1 AM to 5AM|
|Driver may use the 34-hour restart provision only once every 168 hours||168-hour provision no longer applies|
|Driver can use 34-hour restart at anytime|
During the first year of the Trump Administration, they are considering revising laws and regulations that affect hours of service and required meal/break times for truckers. These laws/regulations might also add more truck-only lanes and change the speeds at which cars and trucks would be allowed to travel. Through its anti-regulation rule, the Trump administration has stopped the implementation of a truck speed limit rule. This rule would have set different speed limits for trucks than for cars and would have allowed monitoring of truck speeds through a new device put on the truck.
Each state regulates drowsy driving in its own way, if at all. In 1997, the state of Washington was one of the first states to attempt to pass legislation addressing drowsy driving. The law, which did not pass, would have charged drivers who drove drowsy with a moving violation and if someone died the driver could be charged under homicide regulations. Most states only have awareness laws, which set up days or weeks to enhance awareness of drowsy driving problems. During these awareness periods the states run public service announcements, drowsy driving classes and post signs on highways. New Jersey and Arkansas are the only states that have standalone drowsy driving laws that address what to do in the event of an accident.
New Jersey: Drivers that have been without sleep for 24 hours are considered to be driving recklessly, comparable to an intoxicated driver. (New Jersey Statutes §2C:11-5)
Arkansas: The state classifies “fatigued driving” as an offense under negligent homicide, punishable by a class A misdemeanor (up to one year in jail and a fine up to $2,500), when the driver involved in a fatal accident has been without sleep for 24 consecutive hours or is in a state of sleep after being without sleep for 24 consecutive hours.,
These laws arose because of a state resident dying in a drowsy-driving vehicle crash in which lack of sleep was the leading cause of the crash. These laws do not make drowsy driving a punishable offense if a driver is pulled over in a drowsy state. The laws make it possible to prosecute someone for a more serious offense like negligent homicide if that driver has not had a certain amount of sleep. Many states have brought cases to court regarding drowsy driving, including Florida, New Jersey, New York, Virginia, and Texas. For example, in Virginia a bus driver was charged with involuntary manslaughter based on drowsy driving regulations. A driver who fell asleep at the wheel in Minnesota received a punishment of 7 years in jail. Actor Tracy Morgan’s accident in 2014 involved a sleep-deprived truck driver who had been awake for more than 24 hours. His case continued until 2017 and raised awareness of the issue of drowsy driving.
In 2016, NHTSA started the Drowsy Driving Research and Program Plan to work with other governmental and outside nonprofit groups to kick-start a national response to drowsiness that will shape the policy of drowsy driving. Some of the key aspects of the project are to start a collection of crash data, educate police officers on questions to ask to find out if someone is driving drowsy, and initiate a national public service announcement education campaign. For example, the program has started to put slogans on highway signs and used videos and public service announcements on the Internet and in driver’s ed materials to inform drivers about the dangers of drowsy driving.
As individuals the best way to reduce accidents caused by drowsy driving is to be aware of the signs of drowsy driving and to know how to prevent it.
All articles are reviewed and approved by Dr. Diana Zuckerman and other senior staff.
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