Technology Transfer Series
The National Highway Traffic Safety Administration (NHTSA) recently submitted a Report to Congress on the safety impact of permitting right turns at red lights (RTOR). The Energy Policy Act of 1992 directed NHTSA, in consultation with State agencies, to conduct this study with particular emphasis on the impact on pedestrian safety. The report summarizes the current status of state implementation of laws permitting right and left turns at red lights and has a brief review of previous research. It also presents the results of analyses of currently available data assessing the safety impact of permitting right turns on red.
Since January 1, 1980, all 50 states and the District of Columbia and Puerto Rico have had laws permitting right-turn-on-red unless a sign prohibits the turn. As of January 1, 1994, 43 jurisdictions provided for left-turn-on-red (LTOR) and nine did not. LTOR is permitted only at the intersection of a one-way street with another one-way street.
Two Sources of Data
Two sources of data were used to analyze the problem. NHTSA's Fatal Accident Reporting System (FARS) is a census of all of the fatal crashes in the U.S. The FARS includes a code for a right-turn-on-red vehicle maneuver. However, it does not include information on whether a vehicle was turning right on red or turning right on green at the time of the crash. The data only report that the vehicle was turning right at the time of the crash at an intersection where RTOR is permitted. This distinction is important.
State crash data files of Illinois, Indiana, Maryland, and Missouri include either a code for a right-turn-on-red vehicle maneuver or other codes that make it possible to determine that a RTOR maneuver was executed. The state data cover the years 1989 through 1992, except for Illinois where it covers 1989 through 1991.
Since neither FARS nor the state crash files include information for a left-turn-on-red vehicle maneuver, and since there are relatively few intersections where a left-turn-on-red is permissible, an analysis of the safety impact of LTOR was not possible. The incidence of LTOR crashes is undoubtedly extremely low.
Analysis of FARS Data
Thus, less than 0.2 percent of all fatalities involved a right-turning vehicle maneuver at an intersection where RTOR is permitted. FARS, however, does not discern whether the traffic signal was red. Therefore, the actual number of fatal RTOR crashes is somewhere between zero and 84 and may be closer to zero than 84.
Analysis of Four States' Crash Data
In conclusion, there are a relatively small number of deaths and injuries each year caused by right-turn-on-red crashes. These represent a very small percentage of all crashes, deaths, and injuries. Because the number of crashes due to right-turn-on-red is small, the impact on traffic safety, therefore, has also been small. Insufficient data exist to analyze left turn on red.
For a copy of the report, Safety Impact of Permitting Right-Turn-on-Red, contact: Richard Compton, Ph.D., Office of Program Development and Evaluation, NHTSA, NTS-33, 400 Seventh Street, S.W. Washington, DC 20950, or send a fax to (202) 366-7096.
U.S. Department of
400 Seventh Street, S.W. NTS-33
Washington, DC 20590
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