CMF / CRF Details

CMF ID: 7744

Install shoulder rumble strips


Prior Condition:  Roadways without should rumble strips

Category: Shoulder treatments

Study: Validation and Application of Highway Safety Manual (Part D) in Florida, Abdel-Aty et al., 2014

Star Quality Rating:2 Stars  [View score details]
Rating Points Total:60
Crash Modification Factor (CMF)
Adjusted Standard Error:
Unadjusted Standard Error:0.182
Crash Reduction Factor (CRF)
Value:43.6  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:18.2
Crash Type:Run off road
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:
Average Traffic Volume:
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:2007 to 2010
Type of Methodology Used:Before/after using comparison group
Sample Size (crashes):23 crashes before, 12 crashes after
Sample Size (sites):48 sites before, 48 sites after
Sample Size (site-years):96 site-years before, 96 site-years after
Sample Size (miles):43.451 miles before, 43.451 miles after
Sample Size (miles):86.9 mile-years before, 86.9 mile-years after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Mar 08, 2016
Comments:This CMF applies to single-vehicle run-off-road crashes