CMF / CRF Details
CMF ID: 9233
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: | [View score details] |
Rating Points Total: | 135 |
Crash Modification Factor (CMF) | |
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Value: | 0.695 |
Adjusted Standard Error: | |
Unadjusted Standard Error: | 0.094 |
Crash Reduction Factor (CRF) | |
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Value: | 30.5 (This value indicates a decrease in crashes) |
Adjusted Standard Error: | |
Unadjusted Standard Error: | 9.4 |
Applicability | |
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Crash Type: | Run off road |
Crash Severity: | All |
Roadway Types: | Principal Arterial Other |
Street Type: | |
Minimum Number of Lanes: | |
Maximum Number of Lanes: | |
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: | |
Average Traffic Volume: | 3958 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 | |
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Date Range of Data Used: | 2005 to 2014 |
Municipality: | |
State: | FL,IA,NC,OH,PA |
Country: | |
Type of Methodology Used: | Before/after using empirical Bayes or full Bayes |
Sample Size (crashes): | 74 crashes after |
Sample Size (sites): | 335 sites before, 335 sites after |