Study Details

Study Title: Safety Evaluation of Corner Clearance at Signalized Intersections

Authors: Le et al.

Publication Date:FEB, 2018

Abstract: This study evaluates corner clearance at signalized intersections under the Development of Crash Modification Factors program for the Evaluation of Low-Cost Safety Improvements Pooled Fund Study. Geometric, traffic, and crash data were obtained for signalized intersections with various corner clearances from the State of California and City of Charlotte, North Carolina. A cross-sectional analysis was conducted to estimate the effects of corner clearance while controlling for other differences among study sites. The estimated CMFs indicated that more limited clearance (i.e., driveway(s) within 50 ft of the signalized intersection) on receiving corners was associated with increases for all crash types, based on the data included in this analysis. These increases were statistically significant at the 90-percent level or greater for total, fatal and injury, rear-end, sideswipe, right-angle, and nighttime crashes. Only the results for turning crashes were not statistically significant at the 90-percent level. For limiter corner clearance on the approach corners, the results indicated statistically significant reductions in total, fatal and injury, and rear end crashes. The results also indicated reductions in sideswipe and nighttime crashes, and increases in right-angle and turning crashes, but none of these results were statistically significant at the 90-percent level.

Study Citation: Le, T. Q., Gross, F., Harmon, T, & Eccles, K. "Safety Evaluation of Corner Clearance at Signalized Intersections." Report No. 18-03676, Federal Highway Administration, Washington, D.C. (February 2018).

Study Report: Download the Study Report Document


CMFs Associated With This Study

Category: Access management

Countermeasure: Presence of driveway on an intersection approach corner

CMF CRF(%)QualityCrash TypeCrash SeverityRoadway TypeArea Type
0.82185 StarsAllAllNot specifiedNot specified
0.67335 StarsAllAllNot specifiedNot specified
0.79215 StarsAllK,A,B,CNot specifiedNot specified
0.62385 StarsAllK,A,B,CNot specifiedNot specified
0.79215 StarsRear endAllNot specifiedNot specified
0.63375 StarsRear endAllNot specifiedNot specified
0.83174 StarsSideswipeAllNot specifiedNot specified
0.69314 StarsSideswipeAllNot specifiedNot specified
1.03-34 StarsAngleAllNot specifiedNot specified
1.06-64 StarsAngleAllNot specifiedNot specified
104 StarsLeft turn,Right turnAllNot specifiedNot specified
1.01-14 StarsLeft turn,Right turnAllNot specifiedNot specified
0.9464 StarsNighttimeAllNot specifiedNot specified
0.87134 StarsNighttimeAllNot specifiedNot specified

Countermeasure: Presence of driveway on an intersection receiving corner

CMF CRF(%)QualityCrash TypeCrash SeverityRoadway TypeArea Type
1.33-335 StarsAllAllNot specifiedNot specified
1.76-765 StarsAllAllNot specifiedNot specified
1.29-295 StarsAllK,A,B,CNot specifiedNot specified
1.68-685 StarsAllK,A,B,CNot specifiedNot specified
1.36-365 StarsRear endAllNot specifiedNot specified
1.86-865 StarsRear endAllNot specifiedNot specified
1.31-315 StarsSideswipeAllNot specifiedNot specified
1.71-714 StarsAllAllNot specifiedNot specified
1.42-425 StarsAngleAllNot specifiedNot specified
2.02-1025 StarsAngleAllNot specifiedNot specified
1.22-224 StarsLeft turn,Right turnAllNot specifiedNot specified
1.49-494 StarsLeft turn,Right turnAllNot specifiedNot specified
1.29-295 StarsNighttimeAllNot specifiedNot specified
1.67-675 StarsNighttimeAllNot specifiedNot specified