CMF / CRF Details

CMF ID: 10976

Install Edge Lane Road (ELR)

Description: An edge lane road (ELR) belongs to a class of roadways that supports two-way automobile traffic within a single center lane and accommodates vulnerable road users (VRUs), such as bicyclists or pedestrians, in the edge lanes on either side. Automobiles may use the edge lanes to pass approaching vehicles after yielding to any VRUs there. ELRs are alternatively referred to as advisory bike lanes (ABLs), advisory shoulders, or dashed bicycle lanes. An ELR has no centerline. The center lane is separated from the edge lanes with broken lane markings. The broken lane markings indicate a permissive condition allowing motor vehicles to move into the edge lanes after yielding to any VRUs there.

Prior Condition: Two-Lane Undivided Road

Category: Roadway

Study: Safety Considerations for All Road Users on Edge Lane Roads, Williams et al., 2021

Star Quality Rating: 3 Stars   [View score details]
Rating Points Total: 80
Crash Modification Factor (CMF)
Value: 0.56
Adjusted Standard Error:
Unadjusted Standard Error:
Crash Reduction Factor (CRF)
Value: 44   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:
Crash Type: All
Crash Severity: All
Roadway Types: Principal Arterial Other
Street Type:
Minimum Number of Lanes: 2
Maximum Number of Lanes: 2
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather: Not specified
Road Division Type: Undivided
Minimum Speed Limit:
Maximum Speed Limit:
Speed Unit:
Speed Limit Comment:
Area Type: All
Traffic Volume: Minimum of 200 to Maximum of 4349 Annual Average Daily Traffic (AADT)
Average Traffic Volume: 1720 Annual Average Daily Traffic (AADT)
Time of Day: All
If countermeasure is intersection-based
Intersection Type:
Intersection Geometry:
Traffic Control:
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used: 2005 to 2019
State: CO, ID, IN, ME, MA, MN, VT
Type of Methodology Used:
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Aug-11-2021