Everything You Need to Know About Emergency Braking Systems

As icy roads and harsh weather conditions are the norm in Canada, emergency braking systems are vital in helping to prevent collisions and accidents. After George Westinghouse first developed railway braking systems in the late 19th century, the mechanical drum brake - which is considered to be the first modern braking system - was later developed in 1902 by French manufacturer Louis Renault.

This article continues our series on vehicle safety. The previous in this series was an overview of airbags.

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What Are Emergency Brakes?

Every car has a manual emergency brake, with some modern cars also featuring an autonomous braking system. While emergency brakes should be used when there is any kind of imminent crash, they should also be applied when parking to ensure the vehicle is locked into place, which is particularly important when parked on an incline. Because of this, emergency brakes are also referred to as parking brakes. They perform the important role of decelerating the vehicle in the event that the primary brakes fail or are inaccessible.

Manual Emergency Braking

Automatic emergency braking systems aside, there are four types of manual emergency brakes found in cars:

  A stick lever, which is generally found under the instrument panel in older vehicles

  A center lever, which is commonly found between the front seats

  A foot pedal, which is situated left of the other floor pedals

  A push-button on the console controls


When the emergency brake is applied, the brake cable is passed through an intermediate lever which increases the force of the brake action, before being passed through an equaliser which splits the cable in two so that the force can be sent evenly across the two cables connected to the rear wheels. This results in the vehicle being brought to a complete stop while also being locked into place until the brakes are released.

Automatic Emergency Braking (AEB) Systems

Throughout the course of the 20th century, brake technology continued to develop, with automatic emergency braking systems emerging in the early 21st century, initially appearing in some luxury vehicle models.  These systems improve driving safety by detecting potential collisions and applying the brakes independently. The more advanced systems can detect imminent collisions with smaller targets such as pedestrians and bicycles. Some vehicles feature forward collision warning, which alerts the driver to an impending collision with a vehicle or object

Studies have even found that these braking systems could reduce fatal accidents by up to 25%. Other studies have concluded that autonomous emergency braking systems reduce rear-end crashes by 38%. 


Unlike standard parking brakes, autonomous emergency braking systems allow the vehicle to detect and automatically react to potential collisions ahead, slowing down / stopping the vehicle or even steering it out of the way of a collision. Any car that is fitted with an autonomous system must also feature a manual emergency brake, as these systems cannot hold a car in place after it has come to a stop.

It goes without saying that automatic emergency braking is an added safety feature, intended to reduce the frequency and severity of collisions. It is important to remember what it is not: a substitute for alertness and skill on the road.

Emergency Braking Regulations

Despite strong evidence in favour the effectiveness of automatic braking in preventing accidents, it was estimated in 2018 that only 30% of new cars are being fitted with such systems.

US federal regulations state that all vehicles must have some form of emergency braking system, with autonomous braking being required on most newly-registered heavy goods vehicles. Meanwhile, Transport Canada is considering updating the Motor Vehicle Safety Regulations to make automatic emergency braking and pedestrian automatic emergency braking systems mandatory.  As car safety regulations continue to develop, it is likely that more and more vehicles will be fitted with AEB. 


Read our other articles on safety and a variety of topics here.

John Framigllia
Technical Writer
Our technical writer is known for simplifying automotive parts and services. Intuitive with various vehicles and manufacturers, he knows how to simplify complicated problems.