Excessive sleepiness may result in an increased risk of a motor vehicle crash either because the motorist falls asleep while driving or because he experiences reduced attention to road events and driving tasks due to fatigue/sleepiness. These crashes are primarily of the "drift-off-the-road" sort, as driving off the road may reflect the behaviour of a sleepy driver. The amount of legal and scientific evidence regarding driver fatigue is large enough to warrant special attention towards investigating ways of preventing crashes that have drowsiness as a major contributing factor to the cause. The temporal occurrence of these fall-asleep crashes corresponds with the known circadian variations in sleepiness. There is a primary peak in the number of automobile accidents in the early morning hours, and a secondary peak during the mid-afternoon siesta time, around 3:00 p.m. Further, the temporal occurrence of these fall asleep crashes is a function of age. These crashes occur mostly during the late night and early morning hours for persons between 18-45 years of age, and during the afternoon siesta time for the elderly. It is assumed that drivers engage in a variety of behaviours to remain alert at the wheel. However, very little is known about the actual techniques employed to stay awake. This study aims to examine the countermeasures that have been shown to be effective, ineffective, or potentially effective in combating drowsy driving. (Author/publisher)
Abstract