CMF / CRF Details

CMF ID: 4740

Install wider edgelines (4 in to 6 in)

Description: Widen edgelines from 4 inches to 6 inches

Prior Condition:  4 in wide edgelines

Category: Delineation

Study: Safety effects of wider edge lines on rural, two-lane highways, Park et al., 2012

 
Star Quality Rating:3 Stars  [View score details]
Rating Points Total:90
Crash Modification Factor (CMF)
Value:0.962
Adjusted Standard Error:
Unadjusted Standard Error:0.043
Crash Reduction Factor (CRF)
Value:3.8  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:4.3
Applicability
Crash Type:Nighttime
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:
Minimum Speed Limit:
Maximum Speed Limit:
Speed Unit:
Speed Limit Comment:
Area Type:Rural
Traffic Volume:
Average Traffic Volume:
Time of Day:Night
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:2001 to 2007
Municipality:
State:KS
Country:
Type of Methodology Used:Before/after using empirical Bayes or full Bayes
Sample Size (miles):1178 miles before, 1178 miles after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:May 01, 2013
Comments:Crash type also excludes intersection/interchange crashes and winter month crashes