CMF / CRF Details

CMF ID: 9213

Install safety edge treatment

Description: The safety edge is a low-cost treatment that is implemented in conjunction with pavement resurfacing and is intended to help minimize drop-off-related crashes.

Prior Condition:  Drop-off pavement edge

Category: Shoulder treatments

Study: Development Of Crash Modification Factors For The Application Of The Safetyedge Treatment On Two-Lane Rural Roads, Donnell et al., 2017

 
Star Quality Rating:4 Stars  [View score details]
Rating Points Total:120
Crash Modification Factor (CMF)
Value:0.458
Adjusted Standard Error:
Unadjusted Standard Error:0.202
Crash Reduction Factor (CRF)
Value:54.2  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:20.2
Applicability
Crash Type:Head on
Crash Severity:All
Roadway Types:Principal Arterial Other
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:Rural
Traffic Volume:Minimum of 3200 to Maximum of 10167 Annual Average Daily Traffic (AADT)
Average Traffic Volume:5962 Annual Average Daily Traffic (AADT)
Time of Day:Not specified
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 2014
Municipality:Marion Co.
State:FL
Country:
Type of Methodology Used:Before/after using empirical Bayes or full Bayes
Sample Size (crashes):9 crashes before, 6 crashes after
Sample Size (sites):40 sites before, 40 sites after
Sample Size (miles):36 miles before, 36 miles after
Sample Size (miles):165 mile-years before, 127 mile-years after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Jun 17, 2018
Comments:Excludes intersection-related crashes and animal-related crashes.