According to [[scientific]] studies, "driver fatigue causes 40-percent of commercial truck accidents."<ref name="sciencedaily">[http://www.sciencedaily.com/videos/2008/0511-tired_truckers.htm Tired Truckers: Computer Scientists Test Fatigued Driver Behavior]</ref> The National Highway Traffic Safety Administration (NHTSA) estimates that 56,000 fatigue and sleep related crashes occur every year, resulting in over 1500 fatalities.<ref name="smartmotorist" /> Other estimates place the number much higher at around 100,000.<ref name="sciencedaily" />
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According to [[scientific]] studies, "driver fatigue causes 40-percent of commercial truck accidents."<ref name="sciencedaily">[https://www.sciencedaily.com/videos/2008/0511-tired_truckers.htm Tired Truckers: Computer Scientists Test Fatigued Driver Behavior]</ref> The National Highway Traffic Safety Administration (NHTSA) estimates that 56,000 fatigue and sleep related crashes occur every year, resulting in over 1500 fatalities.<ref name="smartmotorist" /> Other estimates place the number much higher at around 100,000.<ref name="sciencedaily" />