The risks of driving on roadways with 50 miles per hour posted speed limit

The occurrence of fatalities on rural roads is twice or more than that on urban roads (National Highway Traffic Safety Administration, 2001). This brief article presents the findings of a paper given at the Traffic Records Forum in Buffalo, NY in 2005. The authors report on the Nebraska Crash Outcome Data Evaluation System (CODES) study undertaken to identify potential risk factors attributable to the increased crash fatality and injury rates on 50 mph roads. Crashes and crash victims were classified into three groups: crashes or people involved in crashes on the roadways with posted speed limits below 50mph, 50mph, and above 50mph. Crash proportions, fatality and injury rates, hospital charge, and odds ratio were compared among the three groups. The authors found that pronounced increases in crash injury and death rates were observed for crashes on 50mph roads. Only 8% of total crashes during 1999-2000 were on 50mph roads, but accounted for 22% of total fatal crashes and 9% of total injury crashes. The authors conclude that higher risks of deaths and serious injuries in crashes on 50mph roads were associated with teen driver involvement, low restraint use, alcohol involvement, single-vehicle fixed object, and rollover crashes as a result of speeding or driving too fast for conditions.