CMF / CRF Details

CMF ID: 7123

Install median barrier

Description:

Prior Condition: No median barrier present

Category: Roadside

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

 
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Crash Modification Factor (CMF)
Value: 2.28
Adjusted Standard Error:
Unadjusted Standard Error: 0.141
Crash Reduction Factor (CRF)
Value: -128   (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 14.11
Applicability
Crash Type: Other
Crash Severity: All
Roadway Types: Principal Arterial Other Freeways and Expressways
Number of Lanes: 4
Road Division Type: Divided by Median
Speed Limit:
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: 2000 to 2007
Municipality:
State: MO, NC, OH
Country: USA
Type of Methodology Used: Before/after using empirical Bayes or full Bayes
Sample Size (sites): 238 sites before, 238 sites after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Nov-01-2015
Comments: This CMF applies to other median-related crashes for flexible barriers installed on four-lane freeways.