There are previous blog articles on speed and its importance within the Safe System approach to road safety. This one on the TRL website covers many of what we see as the principal areas of evidence, namely:

  1. Higher speeds usually mean more collisions.
  2. Higher speeds usually mean more severe injury outcomes – even very modest increases in speed can lead to large increases in injury risk.
  3. This is true at the aggregate level (that is – higher speed traffic means more collisions and more severe injuries) and the individual level (that is – drivers and riders choosing higher speeds are more likely to crash and to have more severe injuries).
  4. Speed enforcement leads to lower speeds, and fewer collisions and injuries.

Despite all this evidence, when we look at free-flow speeds, in which people are free to choose their speed rather than being limited by traffic conditions, in the UK we still have around half of car drivers and a higher proportion of motorcyclists exceeding speed limits on motorways and on 30mph roads, and around a tenth of car drivers (and nearly a third of motorcyclists) doing the same on single-carriageway national speed limit roads.

Society has, it would seem, a blind spot for speed. It is so weird, although to some extent it makes sense. People are ‘protected’ in their cars from the cues to how fast they are really travelling. We did not evolve to appreciate the risks of such high speeds because we rarely experienced them in our evolutionary past. The road system is ‘forgiving’ and nearly all instances of speeding pass without incident, meaning people ‘learn’ that it is ok (until, of course, it is not). But think about it for a minute. The energy released in a crash is proportional to the mass of the object, and the square of its speed. Speed is the one thing that, if we could reduce it, would lead to safety improvements for all road users, in almost all circumstances. The strange thing though is that while we have some tools that work as safety interventions (area-wide traffic calming, speed cameras, speed limits, intelligent speed assistance, among others), we do not appear to match the effectiveness of these tools with our willingness to use them.

We have newspaper headlines that explicitly normalise ‘breaking limits’. Occasionally, we have ministers who announce that they are interested in increasing or scrapping some limits (most recent example). It has been noted before that professionals who provide telematics solutions have been heard joking about how their own product scored them as highly risky, as they needed to speed to reach their trade stand at a road safety conference on time. We have car speedometers that can indicate speeds more than double the speed limit. And – a personal anecdote from one of the authors – we have people claiming that intelligent speed assistance is an infringement of driver choice to choose ‘an appropriate speed’ for the conditions. To be very clear, intelligent speed assistance helps us to drive lawfully. We can of course choose to exceed speed limits and knowingly increase the risk of killing and injuring ourselves and others. It really is that simple.

To our knowledge, no-one sensible demands that we be allowed to ‘break the breath alcohol limit just a little bit’ anymore. No-one suggests that it should be ok for someone to drive without insurance ‘just occasionally’ or run red lights ‘if the conditions allow it’.

This collective narrative about speed kills and maims people because it normalises higher speeds on the roads. It is also very much an anomaly, and specific to speed. To our knowledge, no-one sensible demands that we be allowed to ‘break the breath alcohol limit just a little bit’ anymore. No-one suggests that it should be ok for someone to drive without insurance ‘just occasionally’ or run red lights ‘if the conditions allow it’. And no-one describes Electronic Stability Control as an infringement on driver choice to brake ineffectively. Odd attitudes seem to apply more to speed than to other risk factors in road use.

Perhaps it is something about expression, or control. Whatever the reason, it is ridiculous, and if you hold attitudes along these lines, you are wrong, and you need to change them. We know this is not the most effective way to communicate if we want to change behaviour, but sometimes (and Road Safety Week seems like one of those times) it is important to speak truthfully and from the heart. Without this honesty, we must accept that thousands of people will continue to be killed and injured every year in preventable road collisions. And as the drink driving example shows, we CAN change.

For humanitarian reasons, and for reasons associated with getting more people travelling in an active manner, we need a new societal narrative on speed. TRL supports Brake in maintaining a focus on this critical risk factor.

Richard Cuerden

Richard Cuerden

Richard Cuerden is Director, TRL Academy and is responsible for TRL’s Technical Strategy, and the associated thought leadership and investment activities, designed to enable world-class transport and mobility solutions that underpin the needs of tomorrow’s economy and society. TRL’s vison is to create clean, efficient transport that is safe, reliable, and accessible for everyone. Richard has a strong track record of using real-world evidence to identify safety and environmental priorities and developing transport solutions to prevent and mitigate harmful outcomes. He writes papers, articles/blogs, regularly appears in national media, and presents at conferences. Richard passionately believes in making innovations and research accessible and promoting the adoption and benefits of good science and engineering.

716 Shaun helman

Shaun Helman

Shaun Helman is TRL’s Chief Scientist for Behavioural Sciences. He is an applied cognitive and social psychologist with nearly two decades’ experience in road safety, road user behaviour, and human-technology integration. His research focuses on the safety of young and newly qualified drivers, vulnerable road user safety and work-related road safety. He has written over 120 journal articles and customer reports since 2002 and has presented at numerous national and international conferences on road safety and other transport issues. He represents TRL at the Parliamentary Advisory Council for Transport Safety, acts as a reviewer for several scientific journals and grant bodies, and is a Trustee of the Road Safety Trust.

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TRL is a world leader in transport safety and has developed products and expert services that have been proven to analyse, minimise and prevent road collisions.

In support of Road Safety Week 2023, TRL experts are discussing speed-related road safety topics and considering how this can change make transport safe for everyone.

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