It’s National Drowsy Drivers Awareness Day and driving while too tired is nothing to joke about.  

In fact, one study found that a crash risk is highest if you get fewer than four hours of shuteye a night.  Studies also found that it’s like driving with a blood alcohol concentration roughly 1.5 times the legal limit. 

Tired drivers are more likely to be distracted, slower to react, and prone to dangerous decisions than well-rested drivers. Obvious signs of fatigue include frequent yawning, an inability to keep your eyes open, and drifting into the opposite lane or shoulder of the road. 

Drowsy drivers may find themselves weaving back and forth7 between lanes. They may have trouble maintaining the right speed and keeping an appropriate distance from other vehicles8, and may be unable to react in time to avoid an obstacle. A significant proportion of drowsy driving accidents involve a single driver driving off the road9 or into another lane at high speed. 

If you do find you are drowsy while driving, take regular breaks, and when you notice yourself getting sleepy, pull over and take a 20-minute nap in a safe place. Caffeine, opening the window, and turning up the radio are only short-term fixes and may leave you vulnerable to dangerous “microsleeps.”