CMF / CRF Details

CMF ID: 6832

Widen shoulder

Description:

Prior Condition: Narrower paved shoulder than after condition

Category: Shoulder treatments

Study: Safety Impacts of Highway Shoulder Attributes in Illinois, Bamzai et al., 2011

 
Star Quality Rating: 3 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 0.49
Adjusted Standard Error:
Unadjusted Standard Error:
Crash Reduction Factor (CRF)
Value: 51   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:
Applicability
Crash Type: Fixed object,Head on,Run off road,Sideswipe
Crash Severity: O (property damage only)
Roadway Types: Not specified
Number of Lanes: Multilane
Road Division Type: All
Speed Limit: 35-65
Area Type: Urban
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 : NULL
Average Minor Road Volume : NULL
Development Details
Date Range of Data Used: 2000 to 2006
Municipality:
State: IL
Country: USA
Type of Methodology Used: Before/after using empirical Bayes or full Bayes
Sample Size (crashes): NULL crashes
Sample Size (sites): NULL sites
Sample Size (site-years): NULL site-years
Sample Size (miles): NULL miles
Sample Size (mile-years): NULL mile-years
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Jun-22-2015
Comments: This CMF applies to urban multilane highways with a combined lane width and outside paved shoulder width less than or equal to 20 ft. This CMF applies to shoulder related crashes, defined as head-on, fixed object, sideswipe opposite direction, and run-off-road.