Safety Evaluation of Red Light Camera and Intersection Speed Camera Programs in Alberta

Intersection related crashes constitute more than 20% of fatal crashes in the US. Red light running and high speed have been reported as contributing factors for severe crashes at signalized intersections that can be mitigated by using a system of automated enforcement. Red light cameras (RLC) have been deployed by many jurisdictions in the world. Unlike the RLCs, intersection speed cameras (ISC) have not commonly been used. RLCs have been evaluated by a number of researches; however, few studies quantified spillover effects in evaluating the effectiveness of RLCs. Additionally, little research has been conducted in evaluating the effectiveness of ISCs. In this study, data from various jurisdictions in the Province of Alberta in Canada were used to evaluate the effectiveness of both RLCs and ISCs with special emphasis on spillover effects for RLCs. Observational before and after studies were conducted using the empirical Bayes method to evaluate the changes in the intersections safety performance as a result of individual deployment of both RLCs and ISCs. Spillover effects for RLC intersections during the before period (before RLC activations) by considering a control group of unsignalized intersections were taken into account for before and after evaluation of RLCs. In addition, the magnitudes of spillover effects of the RLCs on all non-RLC signalized intersections (including RLCs during the before period) were also quantified. It was found that severe crashes decreased and property damage only crashes slightly increased for both RLCs and ISCs. Also, angle crashes significantly decreased (37.7% for RLCs and 31.3% for ISCs) and rear-end crashes increased (7.7% for RLCs and 9.4% for ISCs). In terms of spillover effect on all nonRLC signalized intersections, a significant drop in crashes (10.7% for Total, 6.6% for PDO, 22.7% Severe, 2.4% Angle, and 14.6% rear-end crashes) was noted.

• Supplemental Notes:
  • This paper was sponsored by TRB committee ANB40 Traffic Law Enforcement.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Izadpanah, Pedram
  • Thukral, Sheetal
  • Zarei, Hossain
  • Hadayeghi, Alireza
• Conference:
  • Transportation Research Board 94th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2015-1-11 to 2015-1-15
• Date: 2015

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: 13p
• Monograph Title: TRB 94th Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Automated enforcement; Before and after studies; Cameras; Highway safety; Red light running; Signalized intersections; Traffic law enforcement
• Geographic Terms: Alberta (Canada)
• Subject Areas: Highways; Operations and Traffic Management; Safety and Human Factors; I85: Safety Devices used in Transport Infrastructure;

Filing Info

• Accession Number: 01557418
• Record Type: Publication
• Report/Paper Numbers: 15-4704
• Files: TRIS, TRB, ATRI
• Created Date: Mar 20 2015 3:21PM