by W.H. Garcia

Created on: September 23, 2007

Surveys have shown that the prevalence of road accidents related to driver drowsiness might be higher than suggested by statistics compiled from post-accident investigations.

Knipling and Wang (1995) estimated that drowsiness likely contributes to 79000-103000 collisions and 1500 fatalities in the United States annually, a higher estimate than the 56000 collisions identified in police reports [1].

Horne and Reyner (1995) estimated that 20 percent of serious collisions on motorways in the United Kingdom are due to sleepiness [2].

Much focus has been placed on curbing the rise of alcohol related accidents. As a result, other accident-causing factors such as driver fatigue and speeding have been neglected.

As our highway networks are frequently expanded to accommodate the insatiable demand for efficiency and accessibility, it is expected that the problem of driver fatigue would become more prominent as drivers spend more time on the highways. Driver fatigue is also one of the main factors that endanger the life of people engaged in driving professions (for example: tour bus drivers, taxi drivers, truck drivers).

Road monotony has been cited as one major reason for driver fatigue. It is not uncommon for modern highways to stretch for hundreds of miles on end without traffic lights and turns. Unchanging landscape also adds to the problem, especially at night. Other causes include driving alone, drugs and lack of sleep the night before.

Clearly, there are two categories of fatigue. Active fatigue is related to deprivation of sleep and physical exertion. Passive fatigue, on the other hand, develops over time when there appears to be little or no interesting stimulation [3].

In Brazil, there have been reported cases of truck drivers resorting to taking drugs like amphetamines to keep alert during drives. This poses a serious health risk to people involved in these driving professions. Over-reliance on these drugs would also mean more danger on the roads when addicts do not get their usual dosage.

There have been attempts to devise driving systems that would warn drivers of fatigue and prompt them to take short rests before continuing. Most of these systems monitor for head nodding and eye blinking movements that are symptomatic of drowsiness. Alert signals in the form of visual, audio or physical cues (e.g. tightening of seat belt) would then be triggered to warn the driver. Attempts have also been made to create systems that can track how well the driver is doing at lane maintenance.

However, it ultimately depends on the driver whether he or she wants to heed the warning signals. Therefore, education has to play a part also in reminding the driving public not to over-estimate their driving abilities. Guidelines should be given as to how to prevent driver fatigue. For example, drivers should be encouraged to take a short rest after every 3 hours of driving. Also, drivers should have adequate rest before undertaking long trips.

References

[1] Knipling RR, Wang SS. (1995) Revised estimates of US drowsy driver crash problem size based on general estimate system case reviews. Pro. 39th annual Association for advancement of Automotive Medicine, pp. 451-466.

[2] Horne JA, Reyner LA. (1995) Sleep-related vehicle accidents. British Medical Journal, Vol. 310, pp. 556-567.

[3] Ronen A, Oron-Gilad T. (2007) Road Characteristics and Driver Fatigue: A Simulator Study, Traffic Injury Prevention, 8:281-289.

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