CMF / CRF Details

CMF ID: 1485

Install additional signal head (to have one over each approach lane)

Description:

Prior Condition:  No Prior Condition(s)

Category: Intersection traffic control

Study: Making Intersections Safer: A Toolbox of Engineering Countermeasures to Reduce Red-Light Running, McGee et al., 2002

 
Star Quality Rating:1 Star  [View score details]
Rating Points Total:25
Crash Modification Factor (CMF)
Value:0.54
Adjusted Standard Error:
Unadjusted Standard Error:0.098
Crash Reduction Factor (CRF)
Value:46  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:9.8
Applicability
Crash Type:Angle
Crash Severity:All
Roadway Types:Not specified
Street Type:
Minimum Number of Lanes:
Maximum Number of Lanes:
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:Urban
Traffic Volume:
Average Traffic Volume:
Time of Day:All
If countermeasure is intersection-based
Intersection Type:Roadway/roadway (not interchange related)
Intersection Geometry:
Traffic Control:Signalized
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used:
Municipality:Winston Salem
State:NC
Country:usa
Type of Methodology Used:Simple before/after
Sample Size (crashes):87 crashes before, 44 crashes after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Dec 01, 2009
Comments:Author indicated that sites were selected based on locations where improvement is likely to be effective, and not on high crash experience. In this case, regression-to-the-mean is not accounted for in the evaluation, but likely to be minor.