CMF / CRF Details

CMF ID: 6941

Install centerline and shoulder rumble strips

Description: Milled or rolled rumble strips.

Prior Condition:  Existing shoulder rumble strips, centerline rumble strips are added

Category: Roadway

Study: Safety Evaluation of Centerline Plus Shoulder Rumble Strips, Persaud et al., 2015

 
Star Quality Rating:4 Stars  [View score details]
Rating Points Total:110
Crash Modification Factor (CMF)
Value:0.891
Adjusted Standard Error:
Unadjusted Standard Error:0.21
Crash Reduction Factor (CRF)
Value:10.9  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:21
Applicability
Crash Type:Sideswipe
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:Undivided
Minimum Speed Limit:
Maximum Speed Limit:
Speed Unit:
Speed Limit Comment:
Area Type:Rural
Traffic Volume:Minimum of 1282 to Maximum of 20433 Annual Average Daily Traffic (AADT)
Average Traffic Volume:6101 Annual Average Daily Traffic (AADT)
Time of Day:All
If countermeasure is intersection-based
Intersection Type:
Intersection Geometry:
Traffic Control:
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:KY
Country:USA
Type of Methodology Used:Before/after using empirical Bayes or full Bayes
Sample Size (crashes):60 crashes before, 31 crashes after
Sample Size (miles):164 miles before, 164 miles after
Sample Size (miles):604 mile-years before, 764 mile-years after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Nov 01, 2015
Comments:CMF for sideswipe, opposite direction crashes (all severity levels) excludes intersection-related and animal crashes. This may only reflect the benefit of added centerline rumble strips because centerline rumble strips were added to existing shoulder rumble strips.