CMF / CRF Details

CMF ID: 10283

Install safety edge treatment with 1-2 ft. lane widening

Description:

Prior Condition: No Prior Condition(s)

Category: Shoulder treatments

Study: An Alternative Regression-Based Approach to Estimate the Crash Modification Factors of Multiple Treatments Using Before-and-After Data, Galgamuwa, U. and S. Dissanayake., 2018

 
Star Quality Rating: 3 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 0.51
Adjusted Standard Error:
Unadjusted Standard Error: 0.115
Crash Reduction Factor (CRF)
Value: 49   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 11.5
Applicability
Crash Type: All
Crash Severity: All
Roadway Types: All
Number of Lanes:
Road Division Type:
Speed Limit:
Area Type: All
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: 2009 to 2014
Municipality:
State: KS
Country:
Type of Methodology Used: Before/after using empirical Bayes or full Bayes
Sample Size (crashes): 29 crashes after
Sample Size (miles): 72 miles before, 72 miles after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Dec-07-2019
Comments: This is a combined CMF for multiple treatments.

 

The information contained in the Crash Modification Factors (CMF) Clearinghouse is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in the CMF Clearinghouse. The information contained in the CMF Clearinghouse does not constitute a standard, specification, or regulation, nor is it a substitute for sound engineering judgment.