During a power outage, the vehicle and pedestrian displays will be dark and the signalized intersection must be treated as an all-way stop. The following should be followed

  • the first vehicle to come to a complete stop at the intersection goes first
  • if two vehicles arrive and stop at the same time, the one on the right goes first
  • if two vehicles stop at the intersection at about the same time and are facing each other, the one making a left turn yields to the one going straight through; otherwise, both vehicles proceed straight through at the same time
  • in all cases, vehicles yield to pedestrians
  • report the issue to 311

Unless equipped with battery back-up systems, traffic signals in the affected area will not be operational.

All traffic signals in Toronto are equipped with LEDs (Light Emitting Diodes) instead of incandescent bulbs. High-efficiency, long-life LEDs facilitate energy cost savings since they consume 80 – 90 per cent less energy than comparable incandescent bulbs. LEDs also facilitate savings in maintenance costs since they are replaced every five years compared to the one year cycle for incandescent bulbs. Compared to incandescent bulbs, LEDs provide an annual energy savings of more than 20,000 kilowatts resulting in an annual savings of about two million dollars. The energy savings translates into a reduction of five million kilograms of carbon dioxide each year.

Due to the reduction in energy consumption, it is now more feasible to install battery back-up systems, also called uninterruptable power supplies (UPS), at signalized intersections. In the past, the installation cost of a UPS would be prohibitive since a larger capacity UPS would be required to continue the full operations of the traffic signals equipped with incandescent bulbs. Now that all Toronto signals are equipped with LEDs, it is possible to install UPS at signalized intersections at a more reasonable cost. Toronto has a program to install UPS at major signalized intersections across the city to ensure that signals continue to function during a power failure. A UPS can operate a signalized intersection in a fully functional mode for six to eight hours and in an emergency all-red flash mode for an additional four to six hours. As of June 2019, 111 UPS have been installed at signalized intersections.

Traffic signal backplates (also called backboards) are thin plates of material that surround traffic signal indications. They are intended to improve the visibility of a traffic signal by providing a consistent and controlled-contrast background. The addition of narrow strips of retroreflective tape or sheeting around the border of the backplates enhances the visibility of traffic signals which leads to fewer crashes at signalized intersections.

Retroreflective borders also enhance the visibility of traffic signals for aging and color-vision impaired drivers, better enabling them to determine which signal indication is illuminated. Retroreflective borders also alert drivers to signalized intersections during power outages when the signals would otherwise be dark and non-reflective signal heads and backplates would be less conspicuous.