CMF / CRF Details

CMF ID: 7692

Change from protected only to flashing yellow arrow protected/permissive left turn with time of day operation

Description: Change from protected only to FYA - protected/permissive left turn with time of day operation

Prior Condition:  Protected phasing

Category: Intersection traffic control

Study: Safety Effectiveness of Flashing Yellow Arrow: Evaluation of 222 Signalized Intersections in North Carolina, Simpson and Troy, 2015

 
Star Quality Rating:2 Stars  [View score details]
Rating Points Total:55
Crash Modification Factor (CMF)
Value:2.732
Adjusted Standard Error:
Unadjusted Standard Error:1.053
Crash Reduction Factor (CRF)
Value:-173.2  (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:105.3
Applicability
Crash Type:Left turn
Crash Severity:All
Roadway Types:Not specified
Street Type:
Minimum Number of Lanes:
Maximum Number of Lanes:
Number of Lanes Direction:
Number of Lanes Comment:
Crash Weather:Not specified
Road Division Type:
Minimum Speed Limit:35
Maximum Speed Limit:45
Speed Unit:mph
Speed Limit Comment:
Area Type:Not specified
Traffic Volume:
Average Traffic Volume:
Time of Day:All
If countermeasure is intersection-based
Intersection Type:Roadway/roadway (not interchange related)
Intersection Geometry:4-leg
Traffic Control:Signalized
Major Road Traffic Volume:Minimum of 18000 to Maximum of 41000 Annual Average Daily Traffic (AADT)
Minor Road Traffic Volume:Minimum of 3000 to Maximum of 32000 Annual Average Daily Traffic (AADT)
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used:2003 to 2013
Municipality:
State:NC
Country:
Type of Methodology Used:Other before/after
Sample Size (crashes):8 crashes before, 20 crashes after
Sample Size (sites):16 sites before, 16 sites after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Nov 01, 2015
Comments:Target crashes are defined as "left-turn same roadway crashes with the left-turner on an approach treated with FYA and occurring during the time of day when FYA is in operation".