Background: Automatic emergency braking systems

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Automatic emergency braking (AEB) is a technology that monitors a vehicle’s surroundings when it is in motion, and automatically applies the brakes if an imminent crash is detected. The system doesn’t replace the driver’s reaction, but is a last resort to reduce speed if a driver doesn’t react. By slowing the vehicle before a collision, the collision will be less severe, and in some cases it could be completely avoided.

Automatic emergency braking systems could help in various situations. The most common is when a vehicle is about to rear-end another vehicle that’s either stopped or travelling at a slower speed in the same direction. Some systems can also detect and intervene when it senses a pedestrian, cyclist, or other obstacles. These extra capabilities are more complex and cost more money.

We’ve been studying automatic emergency braking for several years now. The results of this work show that the system slows a vehicle before a collision and helps keep drivers and passengers safe. Our research is consistent with other studies that have found that vehicles with automatic emergency braking are involved in fewer rear-end collisions. Reducing the speed of collisions can also help reduce injuries for vulnerable roads users, like pedestrians and cyclists.

There’s no guarantee that an automatic emergency braking system will always intervene. Some types of weather, like snow or rain, could keep the system from detecting an obstacle. Even the sun being low in the sky could affect it how it operates. Regardless, we expect that the technology will continue to evolve. System performance and reliability will improve, and the technology will get cheaper over time.

Automatic emergency braking isn’t required on new vehicles in Canada, but some manufacturers include it as a standard or as an optional feature on some models.

In the United States, 20 automakers have committed that automatic emergency braking will be installed as standard equipment on most new light vehicles (passenger cars, multi-purpose passenger vehicles and most pickup trucks) made between September 2025 and August 2026.

As of July 2022, the European Union will require automatic emergency braking as standard equipment for most new heavy vehicles (commercial trucks and most buses). It will be required in light vehicles as of July 2024. By 2026, the systems installed in new light vehicles must also be able to intervene in an imminent collision with a pedestrian.

If we require this technology, we may use outcome-based regulations.

Consultation questions

As part of this consultation, we’d like to know:

  • Do you see any challenges with installing a pedestrian automatic emergency braking system on a vehicle? Can systems be as effective if the pedestrian is the size of a small child instead of an adult?
  • Should automatic emergency braking systems be able to function even at very low speeds? Should it work when the vehicle is at a crawling speed?
  • What is a metric (or set of metrics) that Transport Canada could use to see whether an automatic emergency braking system makes a vehicle safer? What would be the signs of an automatic emergency braking system that doesn’t make a vehicle safer
  • In your opinion, what are the pros and cons of using outcome-based regulations instead of using traditional tests and minimum performance requirements?  Do you have a preference? Why?
  • What information would be beneficial to manufacturers to help them determine if they meet outcome-based regulations?

Coming into force

This is an informal consultation as part of a pre-regulatory process. If a regulatory proposal is created based on this notice, it would be published with a proposed coming into force date in the Canada Gazette, Part I, followed by a formal comment period. You will also have the opportunity to provide feedback during this formal comment period. Any new regulatory requirement would come into force after it is published in the Canada Gazette, Part II.

The regulation may include separate mandatory compliance dates depending on how far the technology has evolved, and how often the systems are being used in light and heavy vehicles.

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