CMF / CRF Details

CMF ID: 235

Convert intersection with minor-road stop control to modern roundabout

Description:

Prior Condition:  No Prior Condition(s)

Category: Intersection geometry

Study: NCHRP Report 572: Applying Roundabouts in the United States, Rodegerdts et al., 2007

 
Star Quality Rating:2 Stars  [View score details]
Rating Points Total:55
Crash Modification Factor (CMF)
Value:0.88
Adjusted Standard Error:0.21
Unadjusted Standard Error:0.17
Crash Reduction Factor (CRF)
Value:12  (This value indicates a decrease in crashes)
Adjusted Standard Error:21
Unadjusted Standard Error:17
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:
Maximum Speed Limit:
Speed Unit:
Speed Limit Comment:
Area Type:Urban
Traffic Volume:
Average Traffic Volume:
Time of Day:
If countermeasure is intersection-based
Intersection Type:Roadway/roadway (not interchange related)
Intersection Geometry:4-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:
Municipality:
State:
Country:
Type of Methodology Used:Before/after using empirical Bayes or full Bayes
Other Details
Included in Highway Safety Manual?Yes. HSM lists this CMF in italics font to indicate that it has a lower reliability than bold font CMFs since it has an adjusted standard error of 0.2 to 0.3.
Date Added to Clearinghouse:Dec 01, 2009
Comments:Countermeasure name changed from "convert two-way stop-controlled intersection to roundabout" to match HSM