20 mph Speed Limit Rejected - A Rare Win
Discussion
Guybrush said:
Casualties in 20mph zones UP by 24%
14/8/12 MSN
The number of people killed or injured on Britain’s 20mph speed-limited roads has risen by nearly a quarter, according to the Department for Transport’s 2011 figures.
Last year, 2,262 casualties in 20mph zones were recorded – albeit 1,966 of them classed as minor injuries – marking a 24% increase on 2010’s toll.
The latest figures have sparked a debate as to whether 20mph zones – often implemented in urban and recreational areas – actually help to improve road safety.
Campaigners have suggested lower speed limits make crashes less likely to occur, and reduce the ramifications when they do, but the latest results cast doubt on this theory.
Local councils were given the power to designate 20mph zones back in 2009, with a view to improving road safety.
According to local transport minister Norman Baker, “it’s vital that speed limits are suitable for local conditions and councils are best placed to determine what these are, based on local knowledge and the views of the community.”
Questioning the argument, Director of Policy at the Institute of Advanced Motorists, Neil Greig, highlighted that the latest evidence on 20mph areas “now seems very mixed and contradictory.”
DfT data shows there were seven deaths in 20mph zones last year, while 289 serious injuries occurred over 2011, a 17% and 39% rise over 2010 statistics respectively.
The latest figures come after it was announced last month that UK road deaths rose for the first time since 2003, with the serious injury toll growing in 2011, the first time since 1994.
The Royal Society for the Prevention of Accidents highlighted the increase in 20mph casualties was worrying, however, they only represented a small number compared with accidents on 30mph roads.
Proportionally however, the UK has much less of its road network designated as 20mph zones when compared to 30mph limit areas.
Yes, this was the story covered by More or Less.14/8/12 MSN
The number of people killed or injured on Britain’s 20mph speed-limited roads has risen by nearly a quarter, according to the Department for Transport’s 2011 figures.
Last year, 2,262 casualties in 20mph zones were recorded – albeit 1,966 of them classed as minor injuries – marking a 24% increase on 2010’s toll.
The latest figures have sparked a debate as to whether 20mph zones – often implemented in urban and recreational areas – actually help to improve road safety.
Campaigners have suggested lower speed limits make crashes less likely to occur, and reduce the ramifications when they do, but the latest results cast doubt on this theory.
Local councils were given the power to designate 20mph zones back in 2009, with a view to improving road safety.
According to local transport minister Norman Baker, “it’s vital that speed limits are suitable for local conditions and councils are best placed to determine what these are, based on local knowledge and the views of the community.”
Questioning the argument, Director of Policy at the Institute of Advanced Motorists, Neil Greig, highlighted that the latest evidence on 20mph areas “now seems very mixed and contradictory.”
DfT data shows there were seven deaths in 20mph zones last year, while 289 serious injuries occurred over 2011, a 17% and 39% rise over 2010 statistics respectively.
The latest figures come after it was announced last month that UK road deaths rose for the first time since 2003, with the serious injury toll growing in 2011, the first time since 1994.
The Royal Society for the Prevention of Accidents highlighted the increase in 20mph casualties was worrying, however, they only represented a small number compared with accidents on 30mph roads.
Proportionally however, the UK has much less of its road network designated as 20mph zones when compared to 30mph limit areas.
AS I said in my last post, you can't draw conclusions from the numbers because the number roads with a 20 mph limit was increasing over the same period.
Devil2575 said:
AS I said in my last post, you can't draw conclusions from the numbers because the number roads with a 20 mph limit was increasing over the same period.
I find it hard to believe that 20mph limits are more dangerous than 30mph limits.But I find it even harder to believe that the statistics above wouldn't have allowed for the increase in in the number of roads with 20mph limits between the two periods considered. That would be either staggeringly incompetent of the people doing the analysis or (perhaps more likely) very dishonest reporting of the analysis.
Zigster said:
Devil2575 said:
AS I said in my last post, you can't draw conclusions from the numbers because the number roads with a 20 mph limit was increasing over the same period.
I find it hard to believe that 20mph limits are more dangerous than 30mph limits.But I find it even harder to believe that the statistics above wouldn't have allowed for the increase in in the number of roads with 20mph limits between the two periods considered. That would be either staggeringly incompetent of the people doing the analysis or (perhaps more likely) very dishonest reporting of the analysis.
The analysis is simply based on changes to absolute figures for accidents/injuries on 20mph roads.
It would however be valid to compare the figures for 20mph roads to the previous figures for the same roads - whether or not those roads were previously 20mph.
Although in this case, any increase in the figures would be more likely to tell us something than a decrease would.
Although in this case, any increase in the figures would be more likely to tell us something than a decrease would.
Edited by Phatboy317 on Thursday 29th January 13:17
Anybody who opposes 20mph limits, and who hopes to dissuade the powers that be from introducing them, if they are going to use the 'increase in accidents' argument is going to need to offer a viable explanation for why that is happening.
They will also need to remember that accident prevention/reduction in severity is not the only reason that such zones are being introduced.
They will also need to remember that accident prevention/reduction in severity is not the only reason that such zones are being introduced.
singlecoil said:
Anybody who opposes 20mph limits, and who hopes to dissuade the powers that be from introducing them, if they are going to use the 'increase in accidents' argument is going to need to offer a viable explanation for why that is happening.
They will also need to remember that accident prevention/reduction in severity is not the only reason that such zones are being introduced.
Or the council must demonstrate that those 'other benefits' are worth the increase in accidents They will also need to remember that accident prevention/reduction in severity is not the only reason that such zones are being introduced.
Dr Jekyll said:
singlecoil said:
They will also need to remember that accident prevention/reduction in severity is not the only reason that such zones are being introduced.
Ah yes, the old Texan sharpshooter argument.speedking31 said:
singlecoil said:
Anybody who opposes 20mph limits, and who hopes to dissuade the powers that be from introducing them, if they are going to use the 'increase in accidents' argument is going to need to offer a viable explanation for why that is happening.
They will also need to remember that accident prevention/reduction in severity is not the only reason that such zones are being introduced.
Or the council must demonstrate that those 'other benefits' are worth the increase in accidents They will also need to remember that accident prevention/reduction in severity is not the only reason that such zones are being introduced.
Devil2575 said:
They can't have taken it into account because there is no data availible on the number of 20 limits and the distance they account for.
The analysis is simply based on changes to absolute figures for accidents/injuries on 20mph roads.
There's data on the number of accidents in 20mph limits but not on the number of (and distance covered by) 20mph limits? Wouldn't the providers of satnav software have that information?The analysis is simply based on changes to absolute figures for accidents/injuries on 20mph roads.
BlueMR2 said:
The rate of accidents dropped massively because no one could afford any fuel in the recession.
Not that either party in government mentioned that when adding a few more cash machines around the place.
So presumably now fuel prices have dropped and wages are rising we should see accidents start to rise again...Not that either party in government mentioned that when adding a few more cash machines around the place.
Lets see what the 2014 figures show.
Zigster said:
Devil2575 said:
They can't have taken it into account because there is no data availible on the number of 20 limits and the distance they account for.
The analysis is simply based on changes to absolute figures for accidents/injuries on 20mph roads.
There's data on the number of accidents in 20mph limits but not on the number of (and distance covered by) 20mph limits? Wouldn't the providers of satnav software have that information?The analysis is simply based on changes to absolute figures for accidents/injuries on 20mph roads.
Zigster said:
Devil2575 said:
They can't have taken it into account because there is no data available on the number of 20 limits and the distance they account for.
The analysis is simply based on changes to absolute figures for accidents/injuries on 20mph roads.
There's data on the number of accidents in 20mph limits but not on the number of (and distance covered by) 20mph limits? Wouldn't the providers of satnav software have that information?The analysis is simply based on changes to absolute figures for accidents/injuries on 20mph roads.
singlecoil said:
Anybody who opposes 20mph limits, and who hopes to dissuade the powers that be from introducing them, if they are going to use the 'increase in accidents' argument is going to need to offer a viable explanation for why that is happening.
They will also need to remember that accident prevention/reduction in severity is not the only reason that such zones are being introduced.
I've encountered a few sections of road, not all of them within 20mph zones but some of them are, which have been shared space areas. The redeveloped sea front in Blackpool is one. The road and the footpath have all been on the same level and paved with the same surface. This leads pedestrians to not realise when they're stepping out into the road in front of traffic. They will also need to remember that accident prevention/reduction in severity is not the only reason that such zones are being introduced.
There's a junction near my office where, if you were walking along not paying attention and you were looking down at the ground, you would walk across the junction in front of turning traffic because there's nothing to distinguish road from footpath.
These roads have been altered now so the roads are tarmaced and are obviously distinguished from the footpaths.
Pedestrians having a false sense of security and not being vigilant enough has been cited as a reason. 20mph zones are sold as making the roads safe havens and pedestrians are encouraged to believe they have priority so they aren't as careful as they still should be.
Traffic calming measures could also be a possibility. There are chicanes on blind bends on a road I regularly use. Traffic islands and built out kerbs force different road users into pinch points.
No one knows with any certainty but it certainly seems, even taking into account the increasing lengths of road covered by 20mph limits, that they aren't having the desired effect in cutting accidents. Combined with the increase in pollution and the fact that, combined with traffic calming, they certainly don't reduce noise, I don't think it's wise to keep rolling out more and more without further investigation into their effectiveness.
Dammit said:
Is a 30-0-30-0-30 pattern desirable, though? I suspect we've all been on the motorway when it's so busy, and people follow so closely, that the traffic starts to show the concertina affect, and you end up braking to a standstill on a road upon which you should never stop.
If you reduce the terminal speed you may increase the average, smoothing the flow from it's overly choppy current state.
I've heard this argument before but its simply not true. What happens is that congestion increases because the flow rate has gone down. The stop start is due to traffic lights etc. and that is not reduced by speed limits and congestion increases stop start due to an increase in barking wave effects. Or perhaps you can point to some actual research that shows I'm wrong?If you reduce the terminal speed you may increase the average, smoothing the flow from it's overly choppy current state.
From your post "congestion increases because the flow rate has gone down", what have you got that supports this?
Given that you then contradict it yourself- "The stop start is due to traffic lights etc".
Is congestion caused by a) weight of traffic b) speed of traffic between stopping points or c) traffic lights?
Given that you then contradict it yourself- "The stop start is due to traffic lights etc".
Is congestion caused by a) weight of traffic b) speed of traffic between stopping points or c) traffic lights?
Edited by Dammit on Thursday 29th January 22:50
Zigster said:
I find it hard to believe that 20mph limits are more dangerous than 30mph limits.
The obvious reason to put a lower limit on road A than on road B is because road A is more dangerous than road B.The question is, how much does the lower limit compensate for the increased danger
Almost. The road is not dangerous in of itself - it's a stretch of tarmac.
Traffic on that road IS dangerous, so the question becomes how much of that danger is reduced via a reduction in (typically) peak speeds.
No traffic at all=no danger.
Road design, location, width etc provides the context - so on a standard motorway traffic moving at an average of 70mph doesn't pose a huge danger, which is born out by the accident statistics.
That changes rather dramatically in a crowded urban environment with lots of junctions - traffic at 70mph would be hugely dangerous.
But of course that misses out all the other reasons you might want to reduce the speed limit, which are not based on danger but could be based on reducing noise, congestion etc.
Traffic on that road IS dangerous, so the question becomes how much of that danger is reduced via a reduction in (typically) peak speeds.
No traffic at all=no danger.
Road design, location, width etc provides the context - so on a standard motorway traffic moving at an average of 70mph doesn't pose a huge danger, which is born out by the accident statistics.
That changes rather dramatically in a crowded urban environment with lots of junctions - traffic at 70mph would be hugely dangerous.
But of course that misses out all the other reasons you might want to reduce the speed limit, which are not based on danger but could be based on reducing noise, congestion etc.
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