CMF / CRF Details

CMF ID: 4706

Convert high-speed rural intersection to roundabout

Description: Convert high-speed rural intersection to roundabout

Prior Condition: Stop controlled intersection (3 or 4 leg)

Category: Intersection geometry

Study: A Statistical Analysis and Development of a Crash Prediction Model for Roundabouts on High-Speed Rural Roadways, Isebrands, 2012

 
Star Quality Rating: 3 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 0.85
Adjusted Standard Error:
Unadjusted Standard Error:
Crash Reduction Factor (CRF)
Value: 15   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:
Applicability
Crash Type: Rear end
Crash Severity: All
Roadway Types: Not specified
Number of Lanes: 1 to 2
Road Division Type:
Speed Limit: 40-65 mph
Area Type: Rural
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: Roundabout
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume : 14000 Annual Average Daily Traffic (AADT)
Average Minor Road Volume : 5600 Annual Average Daily Traffic (AADT)
Development Details
Date Range of Data Used:
Municipality:
State: KS, MD, MN, OR, WA, WI
Country:
Type of Methodology Used: Simple before/after
Sample Size (site-years): 98 site-years before, 98 site-years after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: May-01-2013
Comments: