Speed affects the severity of all crashes. Even when speed doesn’t cause the crash, it’s what will most likely determine whether anyone is killed, injured, or walks away unharmed from that crash.
Many drivers aren’t aware that they can be travelling at the speed limit and still be driving unsafely.
The speed limit is the maximum legal speed that you can travel at on a road in perfect conditions.
However, road conditions are rarely perfect. As a safe driver, you’ll have to look out for changes in traffic, road and weather conditions, and reduce your speed accordingly.
Traffic conditions that you might need to reduce your speed for include:
high volumes of traffic on the road
pedestrians, joggers and cyclists
holiday times when there are lots of visitors on the road
parked cars.
Road conditions you should reduce your speed for include:
bumpy or narrow areas on the road
wet, icy or gravel road surfaces
signs warning of hazards such as sharp curves or a slippery surface.
Weather conditions you should reduce your speed for include:
rain, snow and ice
wind
fog
bright sunlight.
As your speed increases:
the distance you need in order to stop increases
you have less time to react
there is a greater chance that other road users will misjudge how fast you are travelling.
The severity of injuries resulting from a crash is directly related to the impact speed of the vehicle – whether or not speeding was a factor in the crash.
Take a look at our current speed advertising campaigns
A small change in speed can make a big difference to the outcome of a crash.
When a vehicle crashes, it undergoes a rapid change of speed. However, the occupants keep moving at the vehicle’s previous speed until they are stopped – either by hitting an object or by being restrained by a safety belt or airbag.
Human bodies are not designed to be hurled against objects at speed, and the faster the speed, the more severe the injuries.
The speeds on a road impact how safe other road users feel to walk, bike, or travel with their children on that same road.
If a pedestrian is hit by a vehicle the severity of their injuries is related to the impact speed.
The international accepted speed to greatly reduce the chances of a pedestrian being killed or seriously injured is 30km/h.
The probability of a pedestrian being killed rises as impact speed increases, it approximately doubles between 30km/h and 40km/h, and doubles again from 40km/h to 50km/h. The risk to vulnerable pedestrians, such as the elderly and young children, is even higher.
Source: ITF/OECD (2018) Speed and Crash Risk.
