Daylight Saving Time Dangers: Deadly Crashes Spike, Studies Show

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The phrase “beware the ides of March” alludes to the dangers that lurk in mid-March, specifically in Shakespeare’s account of Julius Caesar’s assassination on March 15. But while most of us don’t need to worry about death by betrayal, there is a more relatable threat looming for drivers and pedestrians this time of year — daylight saving time. As we spring forward this Sunday, losing just one hour of sleep can be dangerous (or lethal), studies show. Luckily, taking a few precautions before getting behind the wheel or setting out on foot can prevent the worst-case scenario, experts say.

Related: Daylight Saving Time Is a Good Time to Check for Car Recalls

Darker mornings along with the drowsiness that drivers experience after daylight saving time lead to a significant increase in traffic accidents and fatalities, according to a 20-year study published in Current Biology. The study, which examined over 732,000 fatal crashes, showed a 6% increase in fatal-accident risk in the U.S. following daylight saving time, with the biggest impact seen in the morning hours of the days immediately following the time change. After about a week, accidents returned to baseline levels.

Groggy Drivers to Blame

While the study indicates that changes in illumination, specifically during the darker morning commute, may contribute to the increased accident risk following daylight saving time, the bigger concern is sleep deprivation. A separate study from the AAA Foundation for Traffic Safety found that the percentage of crashes involving sleep-deprived drivers is likely much higher than federal estimates indicate. The agency’s research shows that 16% to 21% of all police-reported fatal vehicle crashes likely involve drowsy driving.

According to an AAA press release, “crashes caused by drowsy driving tend to be severe because the driver may not attempt to brake or swerve to avoid a collision, so the resulting impact occurs at a high rate of speed. A drowsy driver may also be startled and lose control of the vehicle.”

Another unsettling finding from a 2018 AAA survey showed that while 96% of drivers view drowsy driving as a serious threat and an unacceptable behavior, many respondents didn’t practice what they preach: 29% reported that they had a hard time keeping their eyes open while driving in the previous month. The disruption of sleep patterns caused by daylight saving time is only exacerbating the problem.

Aside from aiming to get the recommended 7-8 hours of sleep and having an extra cup of coffee before hitting the road, there are some simple steps that drivers and pedestrians can take to reduce the risks this time of year.

Spring Forward Safely

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Just like how cell phones and multimedia systems can cause distractions, taking your eyes off the road to eat or drink can lead to an accident, even if it’s just for a second. “You may feel hungrier due to the time change and eating and drinking while driving can be a visual, manual and cognitive distraction,” wrote a spokesperson for Travelers Insurance in an email to “Don’t take your early morning breakfast from the car — reaching into a food bag or opening up a wrapper can divert your attention even for just a few seconds and cause a sudden accident on the road.” While it’s always necessary to pay attention, it’s even more critical when many drivers are sleep-deprived in the days after the time change. It also pays to plan more time for your commute in the days following daylight saving time; this allows you to slow down in anticipation that other drivers will be off their game.

AAA likens the dangers of drowsy driving to drunk driving and offers these additional tips for drivers in the coming days: Avoid heavy foods before driving, avoid medications that cause drowsiness or other impairment, and for longer trips, schedule a break every two hours or 100 miles.

Watch for Warning Signs

AAA notes that drivers often underestimate their level of drowsiness and calls out several warning signs that indicate you should pull over and take a break or swap drivers, if possible. The common symptoms of drowsy driving include drifting out of your lane, difficulty keeping your eyes open and not remembering the past few miles driven.

Pedestrian Precautions

In a 2022 report, the National Highway Traffic Safety Administration found that while overall traffic fatalities leveled off, the same can’t be said of pedestrian fatalities: Pedestrian and cyclist deaths climbed 2% and 8%, respectively, in the first half of 2022 compared to the prior year. Pedestrians are especially vulnerable after the time change, says AAA.

“Many will find on Monday that their normal morning commutes will be darker than they’re used to, which can be especially dangerous for pedestrians and children waiting at bus stops,” said Terri Rae Anthony, safety advisor for AAA East Central, in a statement.

The agency recommends that pedestrians pay extra attention while walking, specifically near crosswalks. Additionally, pedestrians should wear bright colors or reflective clothing when it’s dark out; carry a flashlight; make eye contact with drivers before crossing the street; walk on the sidewalk or face traffic when walking in the road; and cross at intersections.

Do Driver-Assistance Systems Help?

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Advanced driver-assistance systems like adaptive cruise control and hands-on lane centering are becoming more common on new vehicles and may prevent or reduce the impact of a crash due to driver error (or drowsiness). However, drivers shouldn’t rely on these systems to replace their own attention and alertness. Many safety systems don’t function properly in inclement weather or darkness. Pedestrian detection systems, for example, have been shown to be ineffective in the dark, which presents a greater threat during the darker morning hours following daylight saving time.

Some automakers — like Ford, GM and Subaru — offer camera-based driver-monitoring systems in select vehicles that monitor the driver’s face and alert them if drowsy or distracted driving is detected. Although these systems can be used as an additional warning sign that it’s time to pull over, drivers should still heed the advice above proactively instead of waiting for their vehicle to tell them they are sleep-deprived.

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Former News Editor Jane Ulitskaya joined the team in 2021, and her areas of focus included researching and reporting on vehicle pricing, inventory and auto finance trends. Email Jane Ulitskaya

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