CMF / CRF Details

CMF ID: 321

Install a traffic signal


Prior Condition:  No Prior Condition(s)

Category: Intersection traffic control

Study: NCHRP Report 491: Crash Experience Warrant for Traffic Signals, McGee et al., 2003

Star Quality Rating:4 Stars  [View score details]
Rating Points Total:120
Crash Modification Factor (CMF)
Adjusted Standard Error:0.46
Unadjusted Standard Error:0.39
Crash Reduction Factor (CRF)
Value:-38  (This value indicates an increase in crashes)
Adjusted Standard Error:46
Unadjusted Standard Error:39
Crash Type:Rear end
Crash Severity:K (fatal),A (serious injury),B (minor injury),C (possible injury)
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:
If countermeasure is intersection-based
Intersection Type:Roadway/roadway (not interchange related)
Intersection Geometry:4-leg
Traffic Control:Stop-controlled
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used:
Type of Methodology Used:Before/after using empirical Bayes or full Bayes
Other Details
Included in Highway Safety Manual?No
Date Added to Clearinghouse:Dec 01, 2009
Comments:Countermeasure name has been slightly modified for consistency across Clearinghouse