Driver Fatigue – ‘A Dangerous Form Of Impairment’- Continues To Take Lives

On Tuesday, the National Transportation Safety Board (NTSB) found that driver fatigue led to a deadly multivehicle crash in Phoenix in June 2021 that killed four and injured 11 after a tractor-trailer carrying milk rammed into stopped traffic of passenger vehicles.

The investigation revealed that the driver had less than a six-hour opportunity for sleep the day of the crash, and regularly worked 70 – 80 hours a week. The trucking company did not have a program to manage driver fatigue, had poor oversight over its drivers, and did not enforce its own policies regarding the maximum hours employees could work.

A program to manage driver fatigue, as well as collision avoidance technology, would have prevented the fatal collision, the safety agency said, highlighting the dangers of being drowsy behind the wheel.

New research announced earlier this month by the AAA Foundation for Traffic Safety, a nonprofit research and education association, found that many drivers may be unaware of how drowsy they are, and as a result, fail to take breaks because they may not realize the risks until it’s too late.

“Being drowsy while driving is a dangerous form of impairment, and it does not resolve or improve with continued driving,” David Yang, the AAA Foundation’s president and executive director, said in a statement. “Our goal is to help drivers learn to heed the early warning signs of drowsiness so they can stop, rest, and then continue their journey as safely as possible.”

Drowsy driving plays a significant role in traffic crashes, injuries, and deaths, the safety group noted. Previous research estimated that 16% to 21% of all police-reported fatal vehicle crashes likely involve drowsy driving. Beyond the danger of falling asleep at the wheel, researchers said, drowsiness also reduces drivers’ alertness.

“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,” according to the research.

For the report, “Drowsiness and Decision Making During Long Drives:A Driving Simulation Study,” researchers designed a nighttime highway driving experiment, which included a survey to gauge how drowsy drivers felt and measured the percentage of time their eyes were closed.

The results of the assessment showed that levels of drowsiness generally increased throughout the 3-hour long driving simulation, and while participants were usually aware that they were drowsy, their perceptions about their levels of sleepiness were not always accurate and affected decision-making.

Key findings from the study:

• When drivers rated their level of drowsiness as low, 75% of them were, in fact, moderately or severely drowsy.
• Even when drivers’ eyes were closed for 15 seconds or longer over a one-minute window— indicative of severe drowsiness—one in four still rated their drowsiness as low.
• Drivers very rarely took breaks unless they perceived that they were very drowsy.
• Even when drivers recognized they were extremely drowsy, they still declined 75% of their opportunities to take breaks and kept driving.

“Obtaining sufficient sleep, napping, and consuming caffeine are among the few evidence-based countermeasures that drivers can employ to prevent or mitigate drowsy driving,” the safety group said.

For more information about the research, tips to recognize and avoid drowsy driving, and access to the full report, click here.