CMF / CRF Details

CMF ID: 6953

Increase median shoulder width

Description: Increase median shoulder width

Prior Condition:  Median shoulder with unspecified width

Category: Shoulder treatments

Study: NCHRP Report 794: Median Cross-Section Design for Rural Divided Highways, Graham et al., 2014

 
Star Quality Rating:2 Stars  [View score details]
Rating Points Total:70
Crash Modification Factor (CMF)
Value:0.948
Adjusted Standard Error:
Unadjusted Standard Error:0.037
Crash Reduction Factor (CRF)
Value:5.2  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:3.7
Applicability
Crash Type:Other
Crash Severity:All
Roadway Types:Not specified
Street Type:
Minimum Number of Lanes:4
Maximum Number of Lanes:4
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather:Not specified
Road Division Type:Divided by Median
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:2000 to 2007
Municipality:
State:CA,MO,NC,WA
Country:USA
Type of Methodology Used:Regression cross-section
Sample Size (miles):393 miles
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Nov 01, 2015
Comments:This CMF applies to a one foot increase in median shoulder width for other median-related crashes on four-lane non-freeways with traversable medians.