CMF / CRF Details

CMF ID: 8169

Decrease lane width from 11 feet to 10 feet

Description:

Prior Condition:  11-ft lane width

Category: Roadway

Study: Estimating the safety effects of lane widths on urban streets in Nebraska using the propensity scores-potential outcomes framework, Wood et al., 2015

 
Star Quality Rating:3 Stars  [View score details]
Rating Points Total:95
Crash Modification Factor (CMF)
Value:1.26
Adjusted Standard Error:
Unadjusted Standard Error:0.176
Crash Reduction Factor (CRF)
Value:-26  (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:17.6
Applicability
Crash Type:Sideswipe
Crash Severity:All
Roadway Types:All
Street Type:
Minimum Number of Lanes:2
Maximum Number of Lanes:12
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather:Not specified
Road Division Type:All
Minimum Speed Limit:25
Maximum Speed Limit:60
Speed Unit:mph
Speed Limit Comment:
Area Type:Urban
Traffic Volume:Minimum of 100 to Maximum of 19480 Annual Average Daily Traffic (AADT)
Average Traffic Volume:5348 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
Date Range of Data Used:2003 to 2012
Municipality:
State:NE
Country:USA
Type of Methodology Used:Regression cross-section
Sample Size (crashes):1985 crashes
Sample Size (sites):8901 sites
Sample Size (site-years):89010 site-years
Sample Size (miles):3445 miles
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Nov 10, 2016
Comments:CMF for changing from 11ft to 10ft lane width, sideswipe same direction. Applies to urban principal arterials, minor arterials, and collectors.