CMF / CRF Details

CMF ID: 4479

Changing left turn phasing on one approach from permissive to protected-permissive

Description: CMFs are calculated the intersection level and not the treated approach(es) level.

Prior Condition:  Permissive only left turn phasing on the treated approach

Category: Intersection traffic control

Study: Crash Modification Factors for Changing Left Turn Phasing, Srinivasan et al., 2012

 
Star Quality Rating:4 Stars  [View score details]
Rating Points Total:125
Crash Modification Factor (CMF)
Value:1.091
Adjusted Standard Error:
Unadjusted Standard Error:0.046
Crash Reduction Factor (CRF)
Value:-9.1  (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:4.6
Applicability
Crash Type:Rear end
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:
Maximum Speed Limit:
Speed Unit:
Speed Limit Comment:
Area Type:Urban
Traffic Volume:
Average Traffic Volume:
Time of Day:Not specified
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 11504 to Maximum of 74990 Annual Average Daily Traffic (AADT)
Minor Road Traffic Volume:Minimum of 1466 to Maximum of 42723 Annual Average Daily Traffic (AADT)
Average Major Road Volume :35174 Annual Average Daily Traffic (AADT)
Average Minor Road Volume :18423 Annual Average Daily Traffic (AADT)
Development Details
Date Range of Data Used:
Municipality:Toronto
State:notusa
Country:Canada
Type of Methodology Used:Before/after using empirical Bayes or full Bayes
Sample Size (crashes):1894 crashes before, 1383 crashes after
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Nov 01, 2012
Comments: