CMF / CRF Details

CMF ID: 4194

Conversion of signalized intersection into single- or multi-lane roundabout

Description:

Prior Condition:  Signalized intersection

Category: Intersection geometry

Study: Safety Effectiveness of Converting Signalized Intersections to Roundabouts, Gross et al., 2012

 
Star Quality Rating:4 Stars  [View score details]
Rating Points Total:110
Crash Modification Factor (CMF)
Value:0.81
Adjusted Standard Error:
Unadjusted Standard Error:0.06
Crash Reduction Factor (CRF)
Value:19  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:6
Applicability
Crash Type:All
Crash Severity:All
Roadway Types:Not Specified
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:
Minimum Speed Limit:15
Maximum Speed Limit:35
Speed Unit:mph
Speed Limit Comment:
Area Type:Urban and suburban
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,4-leg
Traffic Control:Roundabout
Major Road Traffic Volume:Minimum of 5300 to Maximum of 52500 Annual Average Daily Traffic (AADT)
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used:2000 to 2009
Municipality:
State:CO,FL,IN,MD,MI,NY,NC,SC,VT,WA
Country:
Type of Methodology Used:Before/after using empirical Bayes or full Bayes
Sample Size (sites):16 sites after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Nov 01, 2012
Comments:Conversion to 2-lane roundabout