CMF / CRF Details

CMF ID: 77

Install changeable "Queue Ahead" warning signs

Description:

Prior Condition: No Prior Condition(s)

Category: Advanced technology and ITS

Study: Handbook of Road Safety Measures, Elvik, R. and Vaa, T., 2004

 
Star Quality Rating: 3 Stars
Crash Modification Factor (CMF)
Value: 1.16
Adjusted Standard Error:
Unadjusted Standard Error: 0.08
Crash Reduction Factor (CRF)
Value: -16   (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 8
Applicability
Crash Type: Rear end
Crash Severity: O (property damage only)
Roadway Types: Principal Arterial Other Freeways and Expressways
Number of Lanes:
Road Division Type:
Speed Limit:
Area Type: Urban
Traffic Volume:
Average Traffic Volume:
Time of Day:
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:
Municipality:
State:
Country:
Type of Methodology Used: Meta-analysis
Other Details
Included in Highway Safety Manual? Yes. HSM lists this CMF in italics font to indicate that it has a lower reliability than bold font CMFs since it has an adjusted standard error of 0.2 to 0.3.
Date Added to Clearinghouse: Dec-01-2009
Comments: Countermeasure name changed to match HSM