CMF / CRF Details

CMF ID: 5514

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)
Value: 5.732
Adjusted Standard Error:
Unadjusted Standard Error: 0.673
Crash Reduction Factor (CRF)
Value: -473.2   (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 67.3
Crash Type: Rear end
Crash Severity: All
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
State: FL
Country: USA
Type of Methodology Used: Regression cross-section
Sample Size (crashes): 15520 crashes
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Apr-30-2014
Comments: CMF for urban freeway interchange areas