CMF / CRF Details

CMF ID: 5128

Provide a raised median


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: 1 Star   [View score details]
Crash Modification Factor (CMF)
Value: 1.031
Adjusted Standard Error:
Unadjusted Standard Error: 0.511
Crash Reduction Factor (CRF)
Value: -3.1   (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 51.1
Crash Type: Vehicle/bicycle
Crash Severity: All
Roadway Types: Principal Arterial Other
Number of Lanes: 4 to 6
Road Division Type: Divided by TWLTL
Speed Limit:
Area Type: Urban and suburban
Traffic Volume:
Average Traffic Volume: 35120 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
State: FL
Country: USA
Type of Methodology Used: Simple before/after
Sample Size (crashes): 8 crashes before, 10 crashes after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Aug-01-2013
Comments: -On low-speed arterials (speed limit of either 35 or 40 mph)