Study Details

Study Title: Development of Crash Modification Factors for Bicycle Treatments at Intersections

Authors: Avelar et al.

Publication Date: AUG, 2023

Abstract: This research developed crash modification factors (CMFs) for bicycle treatments at urban intersections in the United States. The treatments evaluated were the presence of bicycle lanes, extension lines, through bicycle lanes, buffered bicycle lanes, and chevrons along the intersections. The research team compiled and analyzed safety data from Virginia and Texas. The evaluation considered the total number of vehicular crashes, including those crashes resulting in fatality and injury. Safety data collection focused on locations with available bicycle traffic data, or where direct demand models were applicable, and at intersections where bicycle intersection countermeasures were sufficient to conduct a statistical analysis. The research team included bicycle traffic volume counts as a key factor in the analysis, similar to how average annual daily traffic accounts for motor vehicle exposure. For the Virginia study sites, the research team developed estimates of average daily bicycle traffic using actual bicycle counts. For the Texas sites, the bicycle volume estimates were based on direct demand models developed by team members for this evaluation. The analysis found that having separated bicycle lanes and providing a mixing zone between bicyclists and motor vehicles at intersection approaches was associated with reductions in total, fatal and injury, and non-weather-related crashes in Texas. Other evaluations that considered bicycle and vehicular traffic volume, traffic control devices, and other geometric design features yielded CMFs that were not statistically significant. For the economic evaluations, benefit–cost ratios for the two identified treatments were estimated as low as 5.9 when additional right of way was assumed, and up to 113.3 otherwise. Results indicate that these treatments are economically feasible.

Study Citation: Avelar, R., B. Kutela, and X. Li. "Developing Crash Modification Factors for Bicycle Treatments at Intersections." Report No. FHWA-HRT-23-020. Federal Highway Administration. McVean, VA (2023).

Related Citations: Avelar, R., B. Kutela, and X. Li. "Tech Brief - Developing Crash Modification Factors for Bicycle Treatments at Intersections." Report No. FHWA-HRT-23-031. Federal Highway Administration. McVean, VA (2023).

Study Report: Download the Study Report Document


CMFs Associated With This Study

Category: Bicyclists

Countermeasure: Install bicycle lanes

CMF CRF(%)QualityCrash TypeCrash SeverityRoadway TypeArea Type
0.27472.63 StarsVehicle/bicycleAllNot specifiedAll
1.4314-43.143 StarsVehicle/bicycleAllNot specifiedAll
0.163983.613 StarsVehicle/bicycleAllNot specifiedAll
0.349865.023 StarsVehicle/bicycleAllNot specifiedAll
0.95484.523 StarsAllAllNot specifiedAll
1.0278-2.783 StarsAllAllNot specifiedAll
1.1828-18.283 StarsAllAllNot specifiedAll
0.265473.463 StarsAllAllNot specifiedAll
0.33566.53 StarsAllK,A,B,CNot specifiedAll
0.410858.923 StarsAllK,A,B,CNot specifiedAll
0.891310.873 StarsAllK,A,B,CNot specifiedAll
0.583341.673 StarsAllK,A,B,CNot specifiedAll
0.67432.63 StarsAllAllNot specifiedAll
0.57142.94 StarsAllK,A,B,CNot specifiedAll
0.61938.13 StarsAllAllNot specifiedAll
0.66633.43 StarsAllK,A,B,CNot specifiedAll
0.60639.43 StarsAllAllNot specifiedAll
1.236-23.63 StarsAllAllNot specifiedAll

Countermeasure: Install separated bicycle lane

CMF CRF(%)QualityCrash TypeCrash SeverityRoadway TypeArea Type
0.55244.84 StarsAllAllNot specifiedAll
0.45654.44 StarsAllAllNot specifiedAll