Stopping in time is just as important as moving forward.
Vehicle braking experts, WABCO, point out that a vehicle can be equipped with all the latest braking technology, ABS (Anti-lock Braking System), EBS (Electronic Braking System), and RSS (Roll Stability System), and still not stop in time due to other factors involved in braking.
Here are the four components that make up a vehicle total (final) stopping distance.
Human Perception - this can take as long ¼ to ½ second (and even longer if this is during the night with a driver suffering from night blindness) for the brain to realise there is a dangerous situation requiring immediate reaction.
Human Reaction - how long does it take to move the foot from accelerator to brake pedal, impacted by tiredness, fatigue, alcohol and low concentration levels? 0,6 of a second is equal to 22 metres on the road at 120kph.
Vehicle Reaction - this is measured once the brake pedal is applied. This depends on the air or hydraulic pressure in the braking system, brake pedal free-play and internal working order of the brake valves in the system. At 100kph a reaction time of one second means a vehicle travels 27,78m before braking.
Vehicle Braking Capability - the last factor that determines stopping distance. This is subject to multiple factors such as tyre pressure and condition, GVM (gross vehicle mass), coefficient of friction on the road surface, type of braking system, the driver applied braking technique and others.
WABCO calculates the distance to bring a vehicle with good brakes to a full stop at 120kph will be 133 metres. At night headlight beams reach a maximum of 55-60m – this means travelling on a dipped beam at 120kph is over-driving the headlamp range and magnifying the chance of collision during the hours of darkness.