1. Slower speeds improve driver vision

A driver’s peripheral vision is reduced at higher speeds. By proactively slowing speeds in complex road environments, we can influence safe driving behaviour by increasing driver depth perception and field of vision.

2. Slower speeds create vibrant, livable communities

High speeds discourage people from riding their bikes for short trips – because higher speed roads can be perceived as hostile or intimidating environments. Less people riding or walking leads to less physical activity and social interaction. 

3. Slower speeds don’t make trips longer

In cities, average road speeds are more greatly determined by the frequency of intersections, rather than speed limits. In fact, slower speeds can create more uniform speeds and reduce midblock accelerations while adding little to journey times.

A speed limit of 30km/h rather than 50km/h has been shown to only add 18 seconds of travel time between intersections one kilometre apart.

4. Slower speeds improve stopping time

The speed and volume of motor vehicles increase the risk of a crash and the severity of a crash. Driving at a slower speed also helps drivers stop within a shorter distance.

At higher speeds, a car travels further during the reaction time from when the brakes are applied and the stopping distance is greater. This impacts the rate of momentum and energy at the point of the crash, impacting the severity of injury and chances of survival.