CMF / CRF Details

CMF ID: 2228

Implement truck lane restrictions on 4-lane freeways (truck crashes)

Description: Restrict trucks traveling more than 15 mph below posted speed from the left lane on 4-lane interstate segments.

Prior Condition:  No Prior Condition(s)

Category: Roadway

Study: Impact of Truck Lane Restrictions on Four-Lane Freeways in Mountainous Areas, Fontaine, 2008

Star Quality Rating:1 Star  [View score details]
Rating Points Total:15
Crash Modification Factor (CMF)
Adjusted Standard Error:
Unadjusted Standard Error:0.214
Crash Reduction Factor (CRF)
Value:27  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:21.4
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:4
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather:Not specified
Road Division Type:
Minimum Speed Limit:
Maximum Speed Limit:
Speed Unit:
Speed Limit Comment:
Area Type:
Traffic Volume:Minimum of 4041 to Maximum of 24361 Annual Average Daily Traffic (AADT)
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 2006
Type of Methodology Used:Simple before/after
Sample Size (site-years):114 site-years before, 114 site-years after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Dec 01, 2009