Chapter 3 of 716% of exam
Safety Margins & Hazard Awareness
Leaving enough space and time to stop safely is central to avoiding collisions in all conditions.
The two-second rule
In good, dry conditions leave at least a two-second gap between you and the vehicle in front. A simple check is to say a phrase such as 'only a fool breaks the two-second rule' as the vehicle ahead passes a fixed point.
Stopping distances
Overall stopping distance is thinking distance plus braking distance. At 30 mph the typical overall stopping distance is about 23 metres; it rises steeply with speed, reaching around 96 metres at 70 mph.
Adverse weather
In wet weather stopping distances at least double, and on icy roads they can be up to ten times greater than on a dry road. Increase your following gap and slow down well before hazards.