The effects of fatigue are very powerful and can be devastating when combined with driving. For example, your reaction time will be just as poor after 24 hours without sleep as with 0.8 per mille alcohol in the blood. For this reason driving when fatigued is prohibited and the law equates causing an accident while driving fatigued with causing an accident while driving under the influence of alcohol or drugs.

Fatigue and alcohol are considered the single highest factors that cause traffic accidents.

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