The Danger of Drowsy Driving

Distracted driving is responsible for a large number of motor accidents, which is why many state legislatures have passed laws prohibiting texting and driving.  Speeding, reckless driving, improper equipment, and poor maintenance also cause many collisions, and there are laws against all of these.  However, another frequent cause of accidents is driving when a driver is drowsy.

Remaining alert is critical to being able to respond quickly and to properly handle a car, truck, bus or other motor vehicle.  Recent serious crashes in the national news involving buses where a drowsy driver is suspected to be a cause have highlighted this issue.[1]   Unfortunately, drowsy driving is very difficult to legislate against, in part because there is no standard measurable test for drowsiness.[2]   Despite the lack of a legislative solution, we should all be on guard against driving when we are sleepy.  Driving when drowsy not only puts the driver at risk, but also passengers and surrounding vehicles and pedestrians as well. When you are behind the wheel, you need to be attentive to your surroundings to drive safely.

Other than the obvious threat of falling asleep at the wheel, drowsy driving also negatively affects your ability to drive in the following ways:[3]

  • Impaired reaction time, judgment and vision;
  • Problems with information processing and short-term memory;
  • Decreased performance, vigilance and motivation; and
  • Increased moodiness and aggressive behaviors.

Anyone driving drowsy is at risk for causing an accident, but there are certain groups of people among whom drowsy driving is especially prevalent, including:[4]

  • Young people;
  • Shift workers and people with long work hours;
  • Commercial drivers – especially long-haul drivers; and
  • Business travelers.

Government studies show that truck driver fatigue is a contributing factor in at least 13% of all truck crashes.[5] Additionally, the number of crashes involving trucks has increased steadily over the past five years. Unfortunately, despite the obvious dangers of drowsy driving, the trucking industry has managed to persuade the Senate Appropriations Committee to suspend a new Department of Transportation (DOT) regulation aimed at reducing the occurrence of drowsy driving incidents among truck drivers.[6] Whether or not the trucking industry is ultimately successful in its attempts to curb the Department of Transportation’s regulations, you should always be aware of your surroundings when you are driving. Being able to react quickly and appropriately to road hazards is harder to do if you are drowsy.

Fortunately, there are a number of steps you can take to reduce your risk of drowsy driving:[7]

  • If you are planning on driving, make sure that you are adequately rested before your trip.
  • If the trip is a long one, make sure to schedule a break every 2 hours or 100 miles.
  • If possible, have someone accompany you on the trip – this person can help keep you alert during the trip and can share the driving.
  • Make sure to avoid drinking alcohol or taking sedating medications before you get behind the wheel.

How prevalent is this problem?  Among nearly 150,000 adults aged at least 18 years or older in 19 states and the District of Columbia, 4.2% reported that they had fallen asleep while driving at least once in the previous 30 days. Individuals who snored or usually slept 6 or fewer hours per day were more likely to report this behavior.[8]

For all of our safety on the roadways and highways, please try to get adequate sleep before driving.  The consequences of driving while drowsy can be unexpected, tragic and last a lifetime.

[1] See “Drowsy driving remains an elusive highway dilemma”, 5/11/13, at

[2] “There’s not a way to legislate against sleepiness,” said Bruce Hamilton, manager of research and communications at the AAA Foundation for Traffic Safety, which instead focuses on public education campaigns and issuing brochures advising on the dangers. See story at

[3] See “Drowsy Driving: Asleep at the Wheel”, Centers for Disease Control website at  See also for more information.

[4] See article, “Drowsy Driving: Who’s At Risk?”, at

[5] See study, “Report to Congress on the Large Truck Crash Causation Study”, Federal Motor Carrier Safety Administration, Nov. 2005, “Table 8 – Estimated Number of Trucks in All Crashes by Associated Factor”, in pdf form at

[6] The Editorial Board, Drowsy Drivers, Dangerous Highways: The Trucking Industry Wants to Weaken Safety Rules, N.Y. Times (June 13, 2014),

[7] See these and additional preventive tips, see

[8] See data from this study at Centers for Disease Control and Prevention (CDC). “Drowsy driving – 19 states and the District of Columbia, 2009-2010” (1/4/13). MMWR. 2013;61:1033-7, at