CMF / CRF Details

CMF ID: 10269

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: Time-based coordinated signal system

Category: Intersection traffic control

Study: Safety Analysis and Crash Modification Factors of an Adaptive Signal Control Technology along a Corridor, Osorio, J. and R. Benekohal., 2019

Star Quality Rating: 4 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 0.96
Adjusted Standard Error:
Unadjusted Standard Error: 0.15
Crash Reduction Factor (CRF)
Value: 4   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 15
Crash Type: All
Crash Severity: All
Roadway Types: Principal Arterial Other
Number of Lanes:
Road Division Type:
Speed Limit:
Area Type: Urban
Traffic Volume:
Average Traffic Volume:
Time of Day: All
If countermeasure is intersection-based
Intersection Type: Roadway/roadway (not interchange related)
Intersection Geometry: 3-leg,4-leg
Traffic Control: Signalized
Major Road Traffic Volume: Minimum of 19200 to Maximum of 21370 Annual Average Daily Traffic (AADT)
Minor Road Traffic Volume: Minimum of 1300 to Maximum of 15560 Annual Average Daily Traffic (AADT)
Average Major Road Volume : 20063 Annual Average Daily Traffic (AADT)
Average Minor Road Volume : 6928 Annual Average Daily Traffic (AADT)
Development Details
Date Range of Data Used: 2012 to 2016
Municipality: Champaign
State: IL
Type of Methodology Used: Before/after using empirical Bayes or full Bayes
Sample Size (crashes): 134 crashes before, 68 crashes after
Sample Size (sites): 6 sites before, 6 sites after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Dec-07-2019
Comments: This CMF is for Four- and Three-Leg intersections combined and uses calibrated-HSM SPFs.