Stopping distances in the UK Highway Code should be increased because driver thinking time has been underestimated, according to the road safety charity Brake.
Brake asked TRL (Transport Research Laboratory) to provide evidence to show the time taken by car drivers to perceive, recognise and react to emergency situations.
TRL calculated that the average thinking time is 1.5 seconds – more than double the 0.67 seconds set out in the Highway Code.
Brake says this means that average total stopping distance, including thinking time and braking distance, equates to an extra 2.75 car lengths (11 metres) at 30mph, an extra 3.75 car lengths (15 metres) at 40mph – and an additional 6.25 car lengths (25 metres) at 70mph.
As a result, Brake is calling on the Government to increase stopping distances in the next update to the Highway Code.
Jason Wakeford, spokesman for Brake, said: "These figures suggest stopping distances taught to new drivers in the Highway Code fall woefully short. Even though car braking technology has improved in recent years, the majority of the overall stopping distance at most speeds is actually made up of the time taken to perceive the hazard and react.
“The research shows that average thinking time is more than double that set out in the Highway Code. A true understanding of how long it takes to stop a car in an emergency is one of the most important lessons for new drivers.
“Understanding true average thinking time reminds all drivers how far their car will travel before they begin to brake as well as highlighting how any distraction in the car which extends this time, like using a mobile phone, could prove fatal.
“Brake is calling on the Government to increase the stopping distances in the Highway Code as a matter of urgency.”
The RAC is supporting Brake’s call for an update to the Highway Code.
Rod Dennis, RAC spokesman, said: “These findings from Brake and TRL are striking and should be taken seriously. From time to time, new evidence will come to light that means it is necessary to update the Highway Code and perhaps this is one such instance.
“While the ability for cars to be able to brake more quickly has improved, our reaction times clearly haven’t. And arguably, our reaction times might even have got worse due to all the distractions that have made their way into the car environment – none more so than the smartphone that constantly demands our attention.”