CMF / CRF Details

CMF ID: 9778

Install adaptive traffic signal control

Description: ATSC is a traffic management strategy in which traffic signal timings change, or adapt, based on observed traffic demand. These systems utilize increased detection to continually collect data on observed demand, and signal timings are then re-optimized based on current data.

Prior Condition: Traditional traffic signal

Category: Intersection traffic control

Study: Estimating Safety Effects of Adaptive Signal Control Technology using the Empirical Bayes Method, Khattak et al., 2018

 
Star Quality Rating: 3 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 0.79
Adjusted Standard Error:
Unadjusted Standard Error: 0.09
Crash Reduction Factor (CRF)
Value: 21   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 9
Applicability
Crash Type: Multiple vehicle
Crash Severity: All
Roadway Types: Not specified
Number of Lanes:
Road Division Type:
Speed Limit:
Area Type: Urban and suburban
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:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used:
Municipality: Pittsburgh
State: PA
Country: United States
Type of Methodology Used: Before/after using empirical Bayes or full Bayes
Sample Size (sites): 23 sites before, 23 sites after
Sample Size (site-years): 92 site-years before, 69 site-years after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Oct-27-2018
Comments: Applies to crashes within 350 feet of an intersection. InSync adaptive signal control system installed