Study Details

Study Title: Public Good Relative to Right-Turn-on-Red in South Carolina and Alabama.

Authors: Clark et al.

Publication Date: 1983

Abstract: The effects of South Carolina's and Alabama's right-turn-on-red (RTOR) laws on highway safety, fuel consumption, and air pollution were investigated. Accidents at signalized intersections involving right-turning vehicles (RT) before and after the passage of RTOR laws in both states were studied and compared with accidents at signalized intersections that did not involve vehicles making a right turn (NRT). Data for two years before and three years after the effective date of South Carolina's RTOR law were analyzed; the Alabama data included three years before and five years after. The findings of this study indicated that the rate of change of RT property damage accidents in South Carolina was significantly higher for RT property damage accidents in the after after period than the corresponding change for NRT accidents. The rate of change of RT property damage accidents in Alabama was not found to be significantly higher for RT accidents in the after period than the corresponding change for NRT accidents. The findings of this study also indicated that there was no significant difference in the rates of change of RT fatality or injury accidents when compared with the corresponding change for NRT fatality or injury accidents in both South Carolina and Alabama. This study could find no evidence that pedestrian accidents in either state increased as a result of RTOR operations. A further analysis was performed on fuel and travel time savings resulting from RTOR operations. Based on the findings of this study and the benefits estimated, no changes are warranted in either Alabama's or South Carolina's RTOR law, and the laws should remain in effect.

Study Citation: Clark, J. E., Maghsoodloo, S., and Brown, D. B., "Public Good Relative to Right-Turn-on-Red in South Carolina and Alabama." Transportation Research Record 926, Washington, D.C., Transportation Research Board, National Research Council, (1983) pp. 24-31.

Study Report: Download the Study Report Document


CMFs Associated With This Study

Category: Intersection traffic control

Countermeasure: Permit right-turn-on-red

CMF CRF(%)QualityCrash TypeCrash SeverityRoadway TypeArea Type
1.07[B]-71 StarAllAllNot specifiedNot specified