CMF / CRF Details

CMF ID: 6955

Change horizontal alignment

Description: change horizontal alignment

Prior Condition:  horizontal tangent

Category: Alignment

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

 
Star Quality Rating:3 Stars  [View score details]
Rating Points Total:80
Crash Modification Factor (CMF)
Value:1.295
Adjusted Standard Error:
Unadjusted Standard Error:0.162
Crash Reduction Factor (CRF)
Value:-29.5  (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:16.2
Applicability
Crash Type:Other
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: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:2001 to 2005
Municipality:
State:CA
Country:USA
Type of Methodology Used:Regression cross-section
Sample Size (miles):303 miles
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Nov 01, 2015
Comments:This CMF applies to the presence of a horizontal curve versus a tangent for rollover crashes on four-lane freeways with a traversable median.