The two‑second rule: Crucial safety measure often ignored by Canadians
Canadians often head out on the road. Family trips contribute to increased traffic, including on highways and expressways. The two-second rule — and sometimes even the three-second rule — is crucial in such conditions.
Despite attempts to enforce it through regulations regarding maintaining proper distance, this rule remains challenging to follow – partly because it does not apply during overtaking, which can confuse. Experienced drivers are well aware of the two-second rule, while older drivers also apply the three-second rule.
The rule is easy to remember: while driving, you should maintain a two-second gap from the vehicle in front of you. In practice, this means that when passing a post that the car in front has just passed, you should pass it after two, preferably three seconds.
Research from the Massachusetts Institute of Technology confirms the effectiveness of this rule. The studies aimed to analyze drivers' abilities in the context of autonomous driving systems. The study found that drivers over 55 needed an average of 403 milliseconds to notice a danger and 605 milliseconds to decide. In comparison, drivers aged 20 to 25 recorded these times at 220 and 388 milliseconds, respectively.
This means that younger drivers have a reaction time of 0.6 seconds, including an extra 0.1-0.2 seconds for response. On the other hand, older drivers need about 1.5 seconds for a full response. Additionally, activating the braking system takes about another 0.3 seconds.
The time-based rule is easier to apply than the distance in metres, as stated in the Road Traffic Act. Regulations require maintaining a distance equal to half the current speed (at 120 km/h, which is about 60 metres). Watching the milestone posts and counting the time they pass is much more convenient.
This issue is particularly important because failing to maintain proper distance is the fourth most common cause of accidents on Canadian roads. Accidents outside built-up areas are the most tragic – in one in five, a person dies, whereas in built-up areas – in one in fifteen.
