The speed limit is the absolute maximum and does not mean it is safe to drive at that speed irrespective of conditions. Unsafe speed increases the chances of causing a collision (or being unable to avoid one), as well as its severity. Inappropriate speeds are also intimidating, deterring people from walking, cycling or riding horses. Driving at speeds too fast for the road and traffic conditions is dangerous. You should always reduce your speed when
the road layout or condition presents hazards, such as bends
sharing the road with pedestrians, particularly children, older adults or disabled people, cyclists and horse riders, horse drawn vehicles and motorcyclists
weather conditions make it safer to do so
driving at night as it is more difficult to see other road users.
Stopping distances. Drive at a speed that will allow you to stop well within the distance you can see to be clear.
leave enough space between you and the vehicle in front so that you can pull up safely if it suddenly slows down or stops. The safe rule is never to get closer than the overall stopping distance (see Typical Stopping Distances diagram)
allow at least a two-second gap between you and the vehicle in front on high-speed roads and in tunnels where visibility is reduced. The gap should be at least doubled on wet roads and up to ten times greater on icy roads
remember, large vehicles and motorcycles need a greater distance to stop. If driving a large vehicle in a tunnel, you should allow a four-second gap between you and the vehicle in front
If you have to stop in a tunnel, leave at least a 5-metre gap between you and the vehicle in front.