Over 100,000 police-reported crashes involving drowsy driving occur every year, according to the National Highway Traffic Safety Administration. Moreover, these collisions result in more than 1,550 fatalities and 71,000 injuries, notes the National Safety Council.

People across the nation set their clocks back this past weekend, and that means shorter days and more hours for driving in the dark — a particular challenge for commercial fleets. Darker days can affect the body’s natural sleep cycle and increase driver fatigue.

Now is a good time to remind your drivers about the dangers of being tired while behind the wheel.

In a survey conducted by the National Sleep Foundation, approximately half of U.S. adult drivers admit to consistently getting behind the wheel while feeling drowsy. About 20% say they fell asleep behind the wheel at some point in the past year, while another 40% admit to dozing off at least once during their driving history.

Nodding off is no minor issue. For example, some people may 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, according to the National Safety Council.

Fleet operators can keep their drivers safer by reminding them to be cognizant of the following signs of drowsy driving, and urging them to pull over and take a break in the event they feel fatigued. The American Academy of Sleep Medicine says drowsy driving is likely an issue when a motorist experiences any of the following:

• Frequent yawning or difficultly keeping eyes open

• “Nodding off” or trouble holding up head

• Inability to recall driving the last few miles

• Missing road signs, turns, and exits

• Difficulty maintaining consistent speed

• Drifting out of one’s lane

Fleet operators can help driver’s avoid fatigue and boost overall safety by recommending the following action steps drivers can take.

• Get the right amount of sleep. Experts recommend adults consistently get 7 to 9 hours of sleep every night.

• Test for sleep apnea or other disorders. Some drivers may not know that they have an underlying condition that causes drowsiness, such as sleep apnea or insomnia. If they are consistently tired, they should see their physician and get tested.

• Avoid medications that cause drowsiness. Certain prescription drugs will cause drowsiness. Drivers need to work with their doctors to make sure their medications are not interfering with their ability to drive safely.

• Take breaks. Drivers should pull over and take a 10-minute break every two hours if possible. It’s important to stretch one’s legs, move about, and get reinvigorated before getting back behind the wheel.

• Use crash avoidance technologies. While over-reliance is not recommended, some safety technologies like drowsiness alert and lane departure warnings can detect common drowsy driving patterns and warn drivers to stay in their lane or take a break.