Work Truck Logo
MenuMENU
SearchSEARCH

Why Underestimating Drowsiness Leads to Crashes

A new study by the AAA Foundation revealed the most drivers underestimate their level of drowsiness. Here are key findings and common symptoms to look out for.

Why Underestimating Drowsiness Leads to Crashes

Drivers underestimated their drowsiness 75% of the time.

Photo: Work Truck

3 min to read


Drowsy driving is a widely experienced yet often underestimated issue among drivers, leading to a significant role in traffic crashes, injuries, and fatalities.

Ad Loading...

While government statistics may not fully capture its extent, the AAA Foundation for Traffic Safety research suggests that around 16% to 21% of fatal vehicle crashes involve drowsy driving.

Ad Loading...

A recent study by the Foundation revealed that drivers tend to underestimate their drowsiness, leading them to continue driving instead of taking a necessary break.

Educating on the Early Signs

Dr. David Yang, the president and executive director of the Foundation, warns that driving while drowsy is a dangerous form of impairment that doesn't improve with continued driving.

The objective is to educate drivers about early warning signs of drowsiness so they can recognize when it's time to stop, rest, and continue their journey safely.

Drowsiness refers to an increased tendency to fall asleep, which poses the risk of dozing off at the wheel and impairs a driver's alertness.

Crashes caused by drowsy driving can be severe as the driver may not attempt to avoid the collision, resulting in high-speed impacts. Additionally, a drowsy driver may lose control of the vehicle due to being startled.

Ad Loading...

Drivers Underestimated Their Level of Drowsiness

To better understand the impact of drowsiness, researchers conducted a simulated nighttime highway driving experiment covering 150 miles.

Participants could stop at simulated "rest areas" every 20 miles to rest, nap, or refresh themselves. The study found that drivers' perception of their drowsiness didn't always align with their actual level of sleepiness, affecting their decision-making on when to take breaks.

Key findings from the study include:

  • Drivers often underestimated their level of drowsiness, with 75% rating themselves as less drowsy than they actually were.

  • Even when drivers' eyes were closed for extended periods, indicating severe drowsiness, one in four still rated their drowsiness as low.

  • Drivers rarely took breaks unless they felt extremely drowsy, and even then, they declined 75% of their opportunities to rest and kept driving.

The results highlight the need for drivers to recognize their level of drowsiness and be aware of warning signs to avoid falling asleep while driving.

Ad Loading...

Look out for These Common Symptoms  

Common symptoms of drowsiness include difficulty keeping eyes open, lane drifting, and difficulty recalling the last few miles driven.

Drivers should not wait for their bodies to give them an alarm; it's crucial to prioritize getting at least seven hours of sleep before embarking on a journey. AAA recommends several measures to prevent drowsy driving:

  • Travel during times when you are normally awake.

  • Avoid heavy meals before driving.

  • Refrain from using medications that cause drowsiness or impairment.

For longer trips, drivers are advised to take breaks every two hours or every 100 miles, consider traveling with an alert passenger to share driving duties, and not underestimate the benefits of a short nap (around 20 to 30 minutes) at rest stops to stay alert.

AAA supports the development of vehicle technology that can passively monitor drivers for impairment and intervene if necessary, including detecting drowsiness, medical impairment, or the influence of drugs or alcohol.

Ad Loading...

The 2021 Infrastructure Investment and Jobs Act mandates NHTSA to establish testing standards for such technology to enhance road safety.

More Safety & Compliance

Work Truck graphic with “Fall Back” and “Keep Fleet Safety in Focus” over a sunlit field, with a clock illustration on the right.
Safety & Compliance•by Lauren Fletcher•October 30, 2026

Navigating the Effects of Daylight Saving Time on Work Truck Fleets

Discover how daylight saving time impacts work truck fleets and get essential tips for fleet managers and drivers to navigate the "fall back" transition.

Read More →
Three glowing jack-o’-lanterns beneath a full moon, with silhouetted trees and gravestones. Text reads “Keeping Your Drivers Safe?” above the Work Truck logo.
Safety & Compliance•by Lauren Fletcher•October 29, 2026

How Halloween Changes the Job for Work Truck Drivers

Truck traffic doesn’t take the same Halloween break as other drivers. What fleet managers should know about timing, neighborhood stops, and braking data.

Read More →
Safe Driving on Halloween over spooky fall road
Safety & Compliance•by Staff•October 25, 2026

Tips for Driving Safely on Halloween Night

This video features a reminder from the Connecticut Department of Transportation (DOT) and the Connecticut Police Chiefs Association, urging drivers to prioritize safety this Halloween.

Read More →
Ad Loading...
Work Truck graphic with a truck engine and the text “Rerating GVWR — What Fleets Need to Know.”
Safety & Compliance•by Staff•October 22, 2026

Re-rating Gross Vehicle Weight Ratings (GVWR): Why and How it's Done

Sometimes, it is not in a fleet’s best interests to have a vehicle at a given GVWR. Changing the GVWR to a special value can be done, but the process is complicated.

Read More →
Work gloves, a hard hat, tablet, keys, and paperwork sit on a workbench beside a calendar marked “Out of Service,” illustrating the operational disruption caused by a missing work truck.
Safety & Compliance•October 22, 2026

When a Work Truck Gets Stolen, the Real Loss Is Time

A stolen work truck can take more than a vehicle off the road. From tools and access cards to crew downtime, here’s how fleets can prepare for theft before it disrupts the entire workday.

Read More →
Ten members of the America's Road Team pose in front of a white Volvo semi-truck featuring patriotic graphics and the America's Road Team logo at the MCE26 conference and exhibition.
Safety & Compliance•by News/Media Release•October 21, 2026

Volvo Trucks Marks 25 Years as Exclusive Sponsor of America's Road Team

Volvo Trucks North America will serve as the exclusive sponsor of the American Trucking Associations' America's Road Team, marking 25 years of Volvo sponsorship. The group of professional drivers promotes safety and the industry as they travel the country.

Read More →
Ad Loading...
Streamlight Portable Scene Light III displayed on a tripod with a close-up of its LED light head, alongside a badge recognizing it as the 2026 OH&S New Product of the Year winner.
Safety & Compliance•by News/Media Release•October 21, 2026

Streamlight’s High-Output Scene Light Recognized with Occupational Safety Award

Streamlight’s Portable Scene Light III (PSL III) won the 2026 Occupational Health & Safety (OH&S) New Product of the Year Award in the Lighting category.

Read More →
Fleetworthy Expedited Inspection graphic featuring a commercial vehicle inspector walking toward a white semi-truck, with tablet and smartphone displays showing digital driver vehicle examination reports.
Safety & Compliance•by News/Media Release•October 14, 2026

Fleetworthy Expands Expedited Inspection to 5 States

Following its industry-first launch in Nevada, Fleetworthy’s automated inspection technology is now live in California, Michigan, Vermont, and Maine.

Read More →
Red and Black Promo graphic with Kathy Close of JJ Keller that says Behind the Article, Under 26,001 lbs.? IRP May still apply.
Safety & Compliance•by Lauren Fletcher•October 12, 2026

Crossing State Lines in a Light-Duty Work Truck? Check These Rules First

Crossing state lines in a lighter work truck? J.J. Keller's Kathy Close explains when IRP registration, trip permits, and towing rules come into play.

Read More →
Ad Loading...
Safety & Compliance•by Staff•October 12, 2026

Simple Tire Checks That Help Keep Your Business Fleet Moving

A survey found that nearly one in every 10 passenger vehicles has at least one bald tire. What's more, 27% -- more than one in four -- of vehicles are driven with one or more severely under-inflated tires.

Read More →