CMF / CRF Details

Add Two-Way-Left-Turn-Lane (TWLTL) to the major approach of an unsignalized 3-leg intersection

Countermeasure ID: 3005

Description: Install Two-Way-Left-Turn-Lane (TWLTL) on major approach to unsignalized 3-leg intersection

Prior Condition: unsignalized 3-leg intersection with an open median on the major approach

Category: Access management

Study: The Group Least Absolute Shrinkage and Selection Operator "GLASSO" Technique: Application in Variable Selection and Crash Prediction at Unsignalized Intersections, Haleem and Abdel-Aty, 2010

 
Star Quality Rating:3 Stars  [View score details]
Rating Points Total:95
Crash Modification Factor (CMF)
Value:0.69
Adjusted Standard Error:
Unadjusted Standard Error:0.0894
Crash Reduction Factor (CRF)
Value:31  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:8.94
Applicability
Crash Type:All
Crash Severity:All
Roadway Types:Not Specified
Street Type:
Minimum Number of Lanes:2
Maximum Number of Lanes:8
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather:Not specified
Road Division Type:
Minimum Speed Limit:
Maximum Speed Limit:
Speed Unit:
Speed Limit Comment:
Area Type:All
Traffic Volume:
Average Traffic Volume:
Time of Day:All
If countermeasure is intersection-based
Intersection Type:Roadway/roadway (not interchange related)
Intersection Geometry:3-leg
Traffic Control:Stop-controlled
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used:2003 to 2006
Municipality:
State:FL
Country:U.S.A.
Type of Methodology Used:Regression cross-section
Sample Size (sites):1735 sites
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Jul 15, 2011
Comments:

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