CMF / CRF Details

Install Dual Left Turn Lanes (DLTLs)

Countermeasure ID: 11892

Description:

Prior Condition: No Prior Condition(s)

Category: Intersection geometry

Study: Safety Evaluation of Dual Left-Turn Lane Installations in North Carolina, Timothy Nye and Carrie Simpson, 2024

Study Type: Journal Article/Book

 
Star Quality Rating:2 Stars  [View score details]
Rating Points Total:40
Crash Modification Factor (CMF)
Value:0.937
Adjusted Standard Error:
Unadjusted Standard Error:0.06
Crash Reduction Factor (CRF)
Value:6.3  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:6
Applicability
Crash Type:Rear end
Crash Severity:All
Roadway Types:Principal Arterial Other Freeways and Expressways, Principal Arterial Other, Minor Arterial, Major Collector
Street Type:
Minimum Number of Lanes:
Maximum Number of Lanes:
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather:
Road Division Type:
Minimum Speed Limit:
Maximum Speed Limit:
Speed Unit:
Speed Limit Comment:
Area Type:
Traffic Volume:
Average Traffic Volume:
Time of Day:
If countermeasure is intersection-based
Intersection Type:Roadway/roadway (not interchange related)
Intersection Geometry:3-leg, 4-leg
Traffic Control:Signalized
Major Road Traffic Volume:Minimum of 21000 to Maximum of 69000 Annual Average Daily Traffic (AADT)
Minor Road Traffic Volume:
Average Major Road Volume :44667 Annual Average Daily Traffic (AADT)
Average Minor Road Volume :
Development Details
Date Range of Data Used:2005 to 2022
Municipality:
State:NC
Country:
Type of Methodology Used:
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Jan 01, 1970
Comments:This CMF is for 18 DLTL install sites with protected phasing throughout