CMF / CRF Details

CMF ID: 2723

Replace Incandescent Traffic Signal Bulbs with Light Emitting Diodes (LEDs)

Description: At urban signalized intersections, incandescent traffic signal bulbs are replaced by light emitting diodes (LEDs) to improve signal visibility

Prior Condition:  incandescent bulbs in use at traffic signal

Category: Intersection traffic control

Study: Analyzing the Effects of LED Traffic Signals on Urban Intersection Safety, Eustace et al., 2010

 
Star Quality Rating:3 Stars  [View score details]
Rating Points Total:85
Crash Modification Factor (CMF)
Value:1.71
Adjusted Standard Error:
Unadjusted Standard Error:0.156
Crash Reduction Factor (CRF)
Value:-71  (This value indicates an increase in crashes)
Adjusted Standard Error:
Unadjusted Standard Error:15.6
Applicability
Crash Type:All
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:Not specified
Intersection Geometry:Not specified
Traffic Control:Signalized
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used:1999 to 2007
Municipality:Middletown
State:OH
Country:USA
Type of Methodology Used:Before/after using empirical Bayes or full Bayes
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Mar 21, 2011
Comments:The star rating for this CMF was modified from 1 to 2 stars in January 2015. The previous star rating was assigned using a sample size score based only on the crashes in the period after the countermeasure installation. The standard scoring method in the Clearinghouse is to score the sample size based on the crashes before the countermeasure installation plus the expected crashes in the after period.