Road Safety News

The Big 20mph Debate - far from a bore draw

Wednesday 13th November 2013

The Big Debate on the road safety merits of 20mph speed limits lived up to its billing as one of the potential highlights of day one at the National Road Safety Conference in Harrogate.

At the opposite ends of the spectrum, Rod King MBE and Eric Bridgstock  argued passionately about the merits or otherwise of 20mph limits, while Suzette Davenport, Tom Horner and Trish Hirst trod the middle ground while at the same time making their views clear to the audience.

A straw poll, conducted at the outset and repeated at the end of the debate, with the help of the Quizdom interactive technology, suggested a decisive swing towards the 'no' camp when asked the question whether 20mph is good for road safety.

It was interesting to hear in person from Eric Bridgstock, who so often portrays himself as the road safety bogey man in discussion threads on this newsfeed. In reality, he turned out to be much more mild-mannered than perhaps his often ferocious posts on the topic of speed management imply, describing as abhorrent the notion that somehow it is more acceptable to be knocked over at 20mph than at 30mph.

In the opposite camp, Rod King, founder of the 20's Plenty campaign,  talked about 20mph as part of a move to a utopian society in which we all share the roads and enjoy communities that are better and safer places to live.

Suzette Davenport, ACPO lead on roads policing, emphasised the need for speed limits to be realistic and reasonable in the eyes of the motoring public, and enforceable with current resources, suggesting that blanket 20mph limits such as that proposed in the city of Bristol do not fall into that category.

Tom Horner and Trish Hirst, from York City Council, outlined the practical challenges in implementing 20mph on the ground - and in getting drivers to comply with the limits. Tom Horner presented statistics from two established city-wide schemes in Oxford and Portsmouth which suggest that in terms of long-term casualty reduction, the benefts of 20mph schemes are far from conclusive.

At the end of the debate the audience voted with their handsets to indicate that they were less convinced of the benefits of 20mph than they were at the outset of the debate.

One thing is for sure - the 20mph debate will rumble on. But on the evidence of this hour long session - which was expertly chaired by assistant chief constable Sean White from Cleveland Police - Rod King and the 20's Plenty campaigners have much work to do to convince road safety officers of the merits of the cause in which they believe so passionately.


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Further to my previous comment, I remain very sceptical regarding the rational for some 20 zones. Certainly, I am very much in favour of reducing road casualties/improving road safety however, after reading much detail about local schemes and the organisers - I question the motives of some schemes. I suppose the first question would be - what is the objective of imposing a 20 limit? If particular roads (rather than blanket schemes) have an issue with traffic speed causing accidents then introducing a 20 limit makes perfect sense. It does appear however that some schemes seem less about road safety but more about green issues and getting people on their cycles? Whilst I support 20 limits (where there is a road safety issue and speed is demonstrable issue) not everyone embraces "Green" issues - promoting children playing in the street rather than a park, reducing car usage and cycle use? The encouragement of children playing in the street as an example, rather goes against the grain of promoting road safety and cycling proficiency?
Jason, Chichester

Agree (7) | Disagree (3)

As a Chichester resident speaking some months on from 20 implementation (indeed I live within a 20 zone) I have noticed absolutely no impact on speeds in my area at all, probably the reverse in all honesty. Without statistical hard facts regarding injury or pollution levels in my specific area prior to implementation it is almost impossible to gauge whether the cost of the local scheme has been worthwhile? Does it reduce pollution? I really very much doubt it as most of the roads around Chichester are gridlocked most of the time and slower vehicle speeds will normally make pollution worse. Does it promote cycling? To think that instigating 20MPH zones would make people wish to cycle rather than take the car is almost laughable?
Jason, Chichester

Agree (8) | Disagree (2)

At 20mph catalytic converters don't work = greater pollution, not less.
Roger Neal

Agree (10) | Disagree (2)

It appears that the ABD have this issue covered on all angles. 20's Plenty for Us gets criticised for not focussing on the wide benefits of 20mph limits beyond casualty reduction, whilst at the same time you criticise us for focussing on "casualty reduction". It's similar to the way the 20mph limits are said to be "bringing our cities to a stop" and at the same time "no-one takes any notice".

I have said time and time again that it is not about speed "causing" collisions but the fact that "speed prevents them being avoided".

Your comment that "Well, over the last three years there has not been a KSI within Bath & North East Somerset where speed was a causation factor re: cyclists and pedestrians." is insensitive in the extreme. Last night a cyclist died after a "kill and drive off" collision on the Midland Bridge in Bath.

Perhaps you could withdraw your comment.
Rod King, 20's Plenty for Us

Agree (6) | Disagree (13)

In response to Rod's main post (10 posts below this one):

I do not accept that Road Safety Officers lack confidence in their ability to change behaviours, far from it; this is our bread and butter and many effective campaigns and programmes over the past 25 years have shown this to be so.

Neither is it appropriate to cast a generalised aspersion on the accuracy of Tom Horner’s data: Rod, if you have identified an inaccuracy, please contact Tom and let him know exactly what you think is in error and why and he can respond or correct as appropriate. Otherwise, I think that comment should be withdrawn, please.

I found the debate interesting and enlightening, I certainly know much more about the various points of view and motivations than I did beforehand.

With regard to the DfT: we are in very regular contact with the DfT on this and other Road Safety matters and they do also read the Newsfeed!
Honor Byford, Chair, Road Safety GB

Agree (13) | Disagree (0)

Pro 20mph activists just focus on one issue; accidents. But can they name any scheme where there has been the standard three year before/after statistics gathered on emissions? They claim lower emissions, but where are the facts? Of course this must be based on similar vehicle rates.

The DfT National Transport Model forecast suggests that the average person will be cycling 12% less in 2040 than in 2010. So where is this big swing to cycling by imposing these limits?

Driving at 30mph means I travel 30 miles in one hour, driving at 20mph means that the same journey will take one and half hours. Plus the slower you go, the bigger the queue/congestion behind you, just follow a tractor for the same effect.
Terry Hudson, Kent

Agree (15) | Disagree (5)

In Bath & North East Somerset where outside of the day job I am an elected member, 20 limits are being inflicted throughout the authority at the cost of £0.5m and thus far is clearly the most well advertised waste of valuable resources as drivers pay little or no heed. There was not a strong mandate for the limits and my recollection is that the response was of the kind that allows unions to bring the country out on strike.

They seem to be promoted on the basis of making it safer for cyclists and pedestrians. Well, over the last three years there has not been a KSI within Bath & North East Somerset where speed was a causation factor re: cyclists and pedestrians. I would love to be the fly on the dashboard of the cars that those who promote the scheme drive - to watch them never exceed the 20 limit.
Alan Hale - South Gloucestershire.

Agree (15) | Disagree (2)

The 20mph philosophy is centred around the notion that the long-term aim is a change in 'social norm' where the default speed limit in residential areas is 20mph.

We are at a very interesting point in time where some people agree that should be the case and have implemented schemes accordingly, while others disagree so have not. In this situation evidence of the effect of changing the 'social norm' is impossible to collect as almost all of the drivers will still have the mindset that 30mph is the default limit. This means evidence taken from other countries is the best bet in terms of predicting the likely long-term outcomes.

Maybe we should be focusing our efforts on measuring intermediate indicators relating to long-term changes in attitude and behaviour (and comparing those to other countries) as a first step in evaluating the potential effectiveness of 20mph, rather than looking at short-term changes?
Matt Staton, Cambridgeshire

Agree (12) | Disagree (1)

It doesn't seem that putting signs on sticks works very well:

"Sarah Sharp (chairman of 20’s Plenty for Chichester) said the group had already found a lot of people driving at more than 30mph."

Agree (12) | Disagree (1)

The late Kit Kite would say that when you had 4 RSOs discussing something you would end up with at least 5 different opinions!

Wasn't at the debate but spent the weekend with people who wanted 20 MPH in Chichester and got it. They are now getting frustrated by A, the one vehicle keeping to the limit making a natural traffic calming, B, nobody keeping to the limit themselves included! and C, total lack of consultation on what represents residential roads as the authority has included industrial estates!

Sorry, not convinced as the evidence has yet to be put under an independent microscope.
Peter London

Agree (15) | Disagree (1)

Rod has again been allowed 50% more words than the rest of us. Why?

I cannot be alone in suspecting that the supposed public clamour for 20mph limits is more a reflection of Rod's effective campaigning than of what most people really think - Duncan's excellent comment implies the same.

At the risk of repeating myself, it is most important that competent, impartial analysis establishes what the effect of 20mph areas on casualty rates really is. Deaths and injuries matter more than "changing culture" and similar nebulous objectives.
Idris Francis Fight Back with Facts Petersfield

Agree (14) | Disagree (16)

Interesting discussion. What is the experience of those continental European countries which have had 30kph limits for some years?
David Davies, London

Agree (4) | Disagree (0)

I applaud Rod for taking it upon himself to promote these schemes, as an unpaid volunteer as well I gather. However, I can't help feeling that the one body that should also have been present at this debate is the DfT themselves - Rod is simply promoting something that they themselves introduced and authorised. Did RSGB consider inviting the DfT? After all, they are the national traffic/road safety authority - they issue the guidelines, monitor and collate the data, publish the TALs, sign manuals etc. Perhaps those who find fault with these schemes should really be arguing directly with them?
Hugh Jones, Cheshire

Agree (18) | Disagree (2)

So we have 'communities' that aspire to the idea that traffic crawling around at 20 is a good idea. The question I have to ask is where does everybody live that doesn't aspire to that lofty ideal? They obviously can't live IN these aspirational communities otherwise they would surely share these ideals and already be creeping round the residential areas of this fair land. Perhaps they all live in some other non-aspirational 'communities' that are dedicated to slaughtering many people and causing fear and loathing amongst the public. The truth is that if these communities did aspire to this idea then they would all be crawling along like slugs already. The fact that they don't and instead drive at the speeds that provide the safest outcomes shows that this utopia is an ideal shared by only a tiny minority.
Duncan MacKillop, Stratford on Avon

Agree (21) | Disagree (14)

I believe that the problem for road safety professionals is that after years of cut backs and being the poor relation of traffic departments they have little confidence in their ability to influence behaviour change.

Tom Horner looked forward and saw the possibility (hardly proven given the dubious graphing) of reduced effectiveness and saw this as an obstacle to commitment rather than a challenge to address.

Couple this with a police force that has many problems of its own and a disinclination to allocate resources to road safety and the effect was that some of the "don't knows" decided against.

Rather than be dismayed by the outcome of the straw polls, I remain more convinced of the need for Road Safety to look at the bigger picture rather than focus on the micro.

This was referenced in Paul Butcher's presentation. Which I note has not been reported on.

Here is another recent public comment with similar views :-


This debate will, of course, go on, and I look forward to Road Safety Professionals rising to the challenge of making all of our communities better places to be through supporting appropriate speed limits in those communities.

It may well take them out of their comfort zone, but could increase the comfort zone for vulnerable and other road users everywhere.
Rod King, 20's Plenty for Us

Agree (12) | Disagree (23)

Rod and Eric

Much more importantly than being seen as a victory or defeat for either side, the Big Debate once again highlighted the difficulties the 20mph issue poses for road safety professionals.

There can be no denying that 20's Plenty has waged a highly successful campaign and has garnered a significant groundswell of support from communities and politicians.

The problem for road safety professionals is the lack of conclusive evidence to prove that 20mph limits have a positive impact on casualty and collision rates - and the challenges of getting drivers to comply with them, and to see them as realistic and reasonable, when they are applied on a widescale basis.

These were the points made so elequently at National Conference by Suzette Davenport, Trish Hirst and Tom Horner.
Nick Rawlings, editor, Road Safety News

Agree (29) | Disagree (0)

It's you that doesn't get it. You were behind in the vote before the debate started and you lost support during the debate. Road Safety Officers are not fooled by your misguided social engineering experiment.
Eric Bridgstock, Independent Road Safety Research, St Albans

Agree (23) | Disagree (13)


You guys just don't "get it" do you.

It's wide area behavioural change as a result of a changing culture that no longer sees the motor vehicle as the only way and certainly not the preferred way of getting around our communities.

You can't "isolate" cultural change when it's happening everywhere. The aspiration for lower speeds in communities is not being dictated by engineers and planners so that it can be "tried out" or denied here but not there.

20's Plenty is not about the "signs on the sticks" but the democratic process that turns that community aspiration into establishment endorsement.
Rod King, 20's Plenty for Us

Agree (12) | Disagree (22)

I second Dave's comments and as a long-time critic of claims made by Portsmouth and others for casualty reduction, I welcome signs that the tide is turning. Two related points:

There is now ample data out there for many area over 4 years or so, for a competent and (crucially) an independent analysis clarifying the effects of 20mph areas relying only on signs.

There being ample data already, there is no point whatever in more Councils - such as Winchester - running yet another 6 month "trial" that will add nothing significant to existing data. A proper analysis would be cheaper, quicker and more meaningful - so how about it DfT - or RSGB for that matter?
Idris Francis

Agree (15) | Disagree (11)

“The Big Debate” was a great idea when it was announced and, by the sounds of it, it seems to have gone well. It seems a day doesn't go by without a 20mph news item so debates such as this are much needed. I wish I could have been there to hear the arguments from both sides, and especially to hear the Q+A. Did anyone raise the idea of actually finding out the effect of 20mph by using scientific trials? Congratulations to Road Safety GB and everyone involved.
Dave Finney, Slough

Agree (26) | Disagree (5)