CMF / CRF Details

CMF ID: 5148

Provide a raised median

Description:

Prior Condition:  Two-way left-turn lane

Category: Access management

Study: Before-and-after safety study of roadways Where new medians have been added, Alluri et al., 2012

 
Star Quality Rating:2 Stars  [View score details]
Rating Points Total:50
Crash Modification Factor (CMF)
Value:0.735
Adjusted Standard Error:
Unadjusted Standard Error:0.024
Crash Reduction Factor (CRF)
Value:26.5  (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:2.4
Applicability
Crash Type:All
Crash Severity:All
Roadway Types:Principal Arterial Other
Street Type:
Minimum Number of Lanes:4
Maximum Number of Lanes:6
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather:Not specified
Road Division Type:Divided by TWLTL
Minimum Speed Limit:
Maximum Speed Limit:
Speed Unit:
Speed Limit Comment:
Area Type:Urban and suburban
Traffic Volume:
Average Traffic Volume:37578 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:2003 to 2010
Municipality:
State:FL
Country:USA
Type of Methodology Used:Simple before/after
Sample Size (crashes):2234 crashes before, 1569 crashes after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Aug 01, 2013
Comments:-On high-speed arterials (speed limit of either 45, 50, or 55 mph)