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ROAD SAFETY CAMPAIGNER AGAINST MORE 20MPH ZONES

SUE RESTAN

08:50 - 20 December 2006

A Highland road safety campaigner has criticised the continuing roll-out of 20mph speed limits outside schools in Scotland claiming statistics show accidents in such areas to be more severe than those in 30mph zones.

Many schools throughout the north now have 20mph limits on nearby roads and Aberdeen became the first city in Scotland to introduce a 20mph speed limit in parts of its city centre in July this year.

But Paul Smith, who founded the Safe Speed road safety campaign in 2001, said figures recently published by the Welsh Assembly and the Scottish Executive showed people involved in road accidents in 20mph speed limits were more likely to be killed or seriously injured than those involved in accidents in 30mph zones.

And he questioned why the executive continued to support the introduction of the lower limits when the reason for this difference in the severity of injuries was not known.

"The risk is that we could be making things worse by introducing the 20mph limits. It could be that we are choosing the wrong road safety intervention," said Mr Smith, who lives near Tain. He said that the Welsh accident statistics compared its figures with those for the UK as a whole.

The report showed that, throughout the UK in 2005, eight people were fatally injured, 128 were seriously injured and 1,011 suffered slight injuries in 20mph speed limit areas, compared to 990 fatal injuries, 15,458 serious injuries and 143,894 slight injuries in 30mph speed limits.

Mr Smith said this meant the likelihood of someone involved in an accident in a 20mph speed limit being fatally or seriously injured was 11.85%, compared to 10.25% at 30mph.

There were no statistics available specifically for accidents in 20mph and 30mph zones for 2005 in Scotland. The only figures available were from the Road Accidents Scotland 2005 report, which gives the 2001-2005 average by speed limit.

These showed that there had been 87 injury accidents in areas where the speed limit was under 30mph, with no fatal injuries and 14 people seriously injured, whereas, at 30mph, there were 9,957 injury accidents, with 73 people killed and 1,340 seriously injured.

Mr Smith pointed out that the Scottish figures showed a 16.09% chance of being seriously or fatally injured at less than 20mph and a 14.19% chance of serious or fatal injuries at 30mph. And he called for the Department of Transport or the Scottish Executive to commission scientific research of the increased likelihood of serious or fatal injuries in 20mph speed limit areas before more zones were created.

"We need to know the reason why the severity ratio is higher in 20mph speed limits. The assumption is that the slower the traffic is going, the less severe the accidents will be, but it is not that simple," said Mr Smith.

The executive is providing £50million to councils between 2003 and 2008 to introduce 20mph schemes around schools and related safety projects, following a successful pilot project in 1998. Highland Council has so far imposed 20mph limits on roads at 82 schools in the region.

The first school in Highland to be made the subject of the new part-time 20mph limit was Mount Pleasant Primary, in Thurso, Caithness, where the limit was introduced in January 2005. And a Highland Council spokeswoman said it intended to impose 20mph speed limits outside all Highland Council schools by the end of 2008.

She pointed out that the police and the procurator fiscal supported the initiative and that penalties for breaking the 20mph limits would be tough.

An executive spokesman said he believed most people were in favour of the 20mph limits around schools. He said: "The statistics in Scotland show that significantly more fatal and serious accidents happen at 30mph than 20mph. Our policy of bringing in 20mph limits around schools across Scotland has been welcomed by all - parents, police and the emergency services."

_________________
Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Surely the only reliable statistic would be a comparison of KSI accidents before and after the introduction of 20mph limit in the same location.

Anything but that would be better probably.

RTTM is a really big effect. See http://www.safespeed.org.uk/rttm.html

Safe Speed issued the following PR at 13:43:

PR423: The dangerous 20mph zone mystery

news: for immediate release

Safe Speed has today criticised Department for Transport and the Scottish
Executive for failing to consider figures that show 20mph speed limit zones
have crashes which are, on average, more dangerous than those in 30mph zones.

Official figures show that the likelihood of a casualty being fatally or
seriously injured in 2005 was:

11.85% in 20mph zones and
10.26% in 30mph zones

There are a range of possible explanations including:

* A greater proportion of 20mph zone crashes include vulnerable road users

* 20mph zones are created in places where dangers are greatest

* 20mph zones create an illusion of safety, where people take less care

* Some drivers in 20mph zones are so busy attempting to maintain 20mph that
they simply don't brake before impact, possibly because they are looking at
their speedos when something goes wrong.

* 20mph zones encourage drivers to actually travel at 20mph when 10 or 15mph
may have been a better choice.

Paul Smith, founder of the Safe Speed road safety campaign
(www.safespeed.org.uk) said: "It isn't safe to continue to roll out 20mph zones
willy nilly until we have a proper understanding of the higher average crash
severity that they are associated with. As is common with modern road safety
interventions this has not been investigated - they do it because they believe
it should work."

"At first 20mph had to be 'self enforcing' with traffic calming measures used
to create an environment in which 20mph seemed like a natural speed. But since
then there has been 'mission creep' and 20mph zones are being installed widely
without such features."

"If drug companies behaved like this there would be a national outcry, but with
road safety everyone has an opinion. Far too often they claim that 'it's
obvious' that a given intervention should work. This cavalier attitude has
taken us from being the fastest improving country in Europe to the slowest
(in the EU15). Like drugs, road safety interventions come with side effects and
unintended consequences."

"The authorities continue to treat road safety as a problem of vehicle physics
when in fact it is a complex problem of human psychology."

"It's all very well citing examples of 'model' schemes, but with serious
anomalies appearing, the need for properly conducted randomised trials has
never been clearer."

"There's no indication that any of the 'speed kills' policies have made our
roads safer. Speed cameras, traffic calming, speed limit reductions and so on
have all been rolled out across the country with no significant reduction in
road deaths or road crash hospitalisations."

<ends>

Notes for editors
=================

Article in Today's 'Press and Journal':
http://www.thisisnorthscotland.co.uk/di ... K=16224177
&moduleName=InternalSearch&formname=sidebarsearch
or
http://tinyurl.com/yfpcjs


Official figures: RCGB 2005, table 13, last section, casualties:

20mph: (8+128)/1147 = 11.85%
30mph: (990+15,458)/160,342 = 10.26%

_________________
Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

They can't quite make up their mind which story to tell can they ??

Part 1) "An executive spokesman said he believed most people were in favour of the 20mph limits around schools" (surprised we haven't had a poll result yet)

Part 2) Our policy of bringing in 20mph limits around schools across Scotland has been welcomed by all - parents, police and the emergency services( and yet another chance for a misleading poll gone)

Before someone flames me for poo poo ing the idea - we shouldn't need 20 limits near schools at going in /chucking out time - common sense (and the queues of cars outside schools) shouls dictate a sensible speed.
Most schools round here , it's impossible and certainly not advisable to exceed double figures --roads are reduced to one way with kids running around/ crossing the road without looking.
The sign "DANGER SCHOOL CHILDREN" to me means watch out for the little bleeders -they're dangerous.

I disagree. Sure RTTM takes effect if you only sample the year before and the year after, as SCPs tend to, but these areas were likely at 30mph for many many years before being reduced, so there should be plenty of data to establish a meaningful figure. If anything there is a dearth of data on the 20mph zones, since they are so new and there are so relatively few of them. We're currently comparing sample sets of 1147 and 160342 and giving the %ages they kick out equal credibility.

We can't fall into the trap of using the same dodgy statistical methods the pratnerships do to justify their money-grubbing existences.

I would also suggest that factors surrounding the actual act of changing a speed limit, be it up or down, could potentially give a 'blip' in the number/severity of accidents for a short period afterwards. Pedestrians viewing the area as safer when drivers are unaware of the new speedlimit for example. If you know a road fairly well do you genuinely 'see' the speedlimit signs every time you drive into it, or are you more occupied with scanning for hazards that cannot be eliminated through road-knowledge? Potentially also some drivers being aware of the new limit and some not, resulting in an 'unnatural' speed differential between adjacent vehicles.

I maintain that the only way to properly guage the safety of these zones is to take a sample of at least 5 years before and 5 years after the same stretch has been 'twentified' (given that no other changes have been made to the road). Until such data is available for a representative number of sites I would suggest that both sides of the debate would be well-advised to avoid crowing about success or failure, lest they sacrifice their credibility some years down the way. It would also be prudent for authorities not to embark on such widespread implementation of 20's until the data is available, lest they end up 'killing/seriously injuring' more people on the roads through ill-advised action tham they would have through leaving well enough alone (not that they've ever been guilty of that *cough*)!

It's more an issue of site selection than adequate figures. Zones may well be '20-fied' after a spate of crashes due to public pressure, and don't forget that random numbers aren't fixed in time or space. (So you can still get a 10 year hump)




The entire point I'm making is that the data isn't adequate and the research hasn't been properly conducted. The severity ratio anomaly is also present year after year, so it's not some random blip. I'm NOT trying to criticise 20mph zones 'because they are dangerous' rather that we NEED to be able to explain why they produce some 'funny numbers' - and until we know exactly why we should be extremely cautious.

_________________
Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Apart from all the issues concerning the lose of attention and distraction when driving so slowly, continually looking at the speedometer and the simple difficulty of maintaining such a low speed, could it also be something to do with the dynamics of the impact, in which a pedestrian gets push over and down, rather than being pushed aside.