CMF / CRF Details

CMF ID: 8954

Implement systemic signing and visibility improvements at signalized intersections

Description: Replace all signal heads. Replace pedestrian signal heads, pushbuttons, and signs. Install backplates with retroreflective borders on all signal heads. Re-stripe stop lines. Re-stripe crosswalks. Install advance warning signs. Install overhead signs (e.g., R10‐12, R3‐5L, R3‐5R in the MUTCD(4)). Install curb ramps.

Prior Condition: Signalized intersection without systemic signing and visibility improvements

Category: Intersection traffic control

Study: Safety Effects of Low-Cost Systemic Safety Improvements at Signalized and Stop-Controlled Intersections, Le et al., 2017

 
Star Quality Rating: 3 Stars   [View score details]
Crash Modification Factor (CMF)
Value: 0.988
Adjusted Standard Error:
Unadjusted Standard Error: 0.036
Crash Reduction Factor (CRF)
Value: 1.2   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 3.6
Applicability
Crash Type: Rear end
Crash Severity: All
Roadway Types: All
Number of Lanes: 2,4
Road Division Type:
Speed Limit:
Area Type: All
Traffic Volume:
Average Traffic Volume:
Time of Day: All
If countermeasure is intersection-based
Intersection Type:
Intersection Geometry: 3-leg,4-leg
Traffic Control: Signalized
Major Road Traffic Volume: Minimum of 4272 to Maximum of 41100 Annual Average Daily Traffic (AADT)
Minor Road Traffic Volume: Minimum of 111 to Maximum of 20000 Annual Average Daily Traffic (AADT)
Average Major Road Volume : 20447 Annual Average Daily Traffic (AADT)
Average Minor Road Volume : 5864 Annual Average Daily Traffic (AADT)
Development Details
Date Range of Data Used: 2005 to 2014
Municipality:
State: SC
Country:
Type of Methodology Used: Before/after using empirical Bayes or full Bayes
Sample Size (sites): 64 sites before, 64 sites after
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Nov-17-2017
Comments: CMF for 4 mainline lanes and 2 cross street lanes intersections.