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Drowsy driver

Additional NHTSA Research

  • Completed Research Studies
    • Assessment of a Drowsy Driving Warning System for Heavy-Vehicle Drivers A field operational test of an early prototype Drowsy Driver Warning System was conducted based on research and laboratory studies by NHTSA and FMCSA. This project included Control and Test groups consisting of 102 drivers from 3 for-hire trucking fleets using 46 instrumented trucks. Fifty-seven drivers were line-haul, and 45 were long-haul operators. This system uses a near-infrared camera coupled with processing equipment to estimate the driver’s percentage of eye-closure, which has proven to be a reliable measure of driver drowsiness. Results showed that drivers in the Test Group were less drowsy. Drivers with favoring opinions of the system tended to have an increase in safety benefits. Results of the assessment revealed that the early prototype device had an overall positive impact on driver safety. DOT HS 811 117 (PDF 7MB)
    • Development and Testing of Countermeasures for Fatigue-Related Highway Crashes Focus groups of young men and shift workers were convened to gain insight into their experiences, behavior, attitudes, and perceptions regarding drowsy driving. Additional focus groups were conducted to identify possible educational strategies and safety messages that would help them to change behavior or lifestyle choices that contributed to drowsy driving. (Read more)
    • Drowsy Driving and Automobile Crashes An expert panel on driver fatigue and sleepiness was convened to identify and articulate key issues involved in the drowsy-driving problem. Sponsored by the National Center on Sleep Disorders Research of the National Institutes of Health, and NHTSA, this 1998 report provided the foundation for developing future countermeasures on drowsy driving. (Read more)
    • National Survey of Distracted and Drowsy Driving Attitudes and Behaviors Report A survey of drivers was conducted in 2002 to collect data on the nature and scope of the drowsy-driving problem. Thirty-seven percent of drivers had nodded off for at least a moment or fallen asleep while driving at least once:
      • Eight percent had done so in the past six months.
      • Characteristics of Drowsy-Driving Trips:
      • Nodding off or falling asleep recently was most prevalent among drivers ages 21-29 (13%) and males (11%) and least prevalent among drivers over age 64 (4%) and females (5%).
      • Characteristics of Drowsy-Driving Trips:
        • Driver averaged 6 hours of sleep the previous night (and 24% had slept fewer than 5 hours)
        • Driver had been driving for an average of 2.9 hours (but 22% had been driving for more than 4 hours)
        • Occurred while driving on an interstate type highway with posted speed limits of 55 mph or higher (59%)
        • Nearly half (48%) nodded off between 9 p.m. and 6 a.m. (Read more) DOT HS 809 566


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