CMF / CRF Details

CMF ID: 5513

Decrease median width from 64ft to 22ft

Description: Decrease median width from 64ft to 22ft

Prior Condition:  64 ft wide median

Category: Access management

Study: Using multivariate adaptive regression splines (MARS) to develop crash modification factors for urban freeway interchange influence areas, Haleem et al., 2013

Star Quality Rating:4 Stars  [View score details]
Rating Points Total:115
Crash Modification Factor (CMF)
Adjusted Standard Error:
Unadjusted Standard Error:0.329
Crash Reduction Factor (CRF)
Value:-222.7  (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:32.9
Crash Type:All
Crash Severity:K (fatal),A (serious injury),B (minor injury),C (possible injury)
Roadway Types:Principal Arterial Other Freeways and Expressways
Street Type:
Minimum Number of Lanes:4
Maximum Number of Lanes:
Number of Lanes Direction:
Number of Lanes Comment:4 - 6+ Lanes
Crash Weather:Not specified
Road Division Type:Divided by Median
Minimum Speed Limit:
Maximum Speed Limit:
Speed Unit:
Speed Limit Comment:
Area Type:Urban
Traffic Volume:Minimum of 5700 to Maximum of 309000 Annual Average Daily Traffic (AADT)
Average Traffic Volume:95338 Annual Average Daily Traffic (AADT)
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:2007 to 2010
Type of Methodology Used:Regression cross-section
Sample Size (crashes):18525 crashes
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Apr 30, 2014
Comments:CMF for urban freeway interchange areas