...or why unrepresentative data is not reliable.
If you don't have a TomTom device in your vehicle then you may be surprised that if you live in one of the places recently researched by Atkins for the their Evaluation of 20mph limits then it doesn't matter how much you keep within the speed limit your considerate driving was completely ignored. And you wouldn't be alone. The report estimated that the actual number of drivers who were also ignored were in the 97% of vehicles who's speed they never measured.
Atkins and DfT decided that in order to gather information on vehicle speeds in 20mph streets in 12 case study 20mph areas and compare them with 3 other 30mph areas then they would use data captured from high end TomTom SatNavs or vehicles with in-built TomTom in-car devices. This is termed Floating Car Data (FCD).
You may therefore wonder just how accurate and representative their statistics and research were if it only included 3% of vehicles. We did as well, so we did some of our own research.
Rod King published Government publishes 20mph evaluation report in Press Releases 2018-12-06 09:09:02 +0000
Today the government published its long awaited report evaluating 20mph limit implementations. We welcome the report. It has been a long time coming since 2014 when it was commissioned.
And in that time there have been nearly half a million casualties on streets with a 30mph limit.
The report only evaluated a small number of case studies which in themselves only covered part of an authority. There are some useful indicators in the report, particularly around the negative aspects of police failing to routinely enforce 20mph limits and the need for national engagement and awareness on the benefits of reducing speeds below 30mph in residential and other roads.
However, we have major reservations about the primary data used in the report around speed reductions and the complete failure of the study to look at sufficient casualty figures to be able to draw any conclusions that would be statistically credible. These were key reasons for the commissioning of the report and we are amazed at the choice of data measured which appears to be based on measuring what is available rather than what is meaningful.Read more
Here are the 60 second videos we recorded at our 20's Plenty for Wales Conference from presenters and delegates.
Note that this page may take a while to load.Read more
Rod King published 20’s Plenty for Wales – 20mph Conference Report: #20Wales in Press Releases 2018-10-02 23:22:47 +0100
A sell out conference of 100 delegates met in Cardiff to share best practice on how to make streets healthier in Wales by reducing road risk at source through 20mph limits with a focus on 20mph as a national urban default.
Click on each presenter to open their presentation or 60 second voxpopRead more
Rod King commented on LA Enforcement explained 2018-09-13 16:10:49 +0100Not yet, but we believe that several are considering it.
Rod King commented on 20mph Signage Regulation Changes 2018-09-09 18:35:22 +0100Dear Graham
You will be pleased to know that on entering a 20mph limit or zone there is a large sign that is 600cm across or in diameter. In old units that is 2ft wide. Hence there is no reason why an aware driver would not notice such a sign. Its the same size as when you enter a 30mph limit. Indeed, it iss the same size as the one you say you noticed on exiting a limit.
20mph limits are now very common and 25% off the UK population live in local authorities where 20mph is the limit on most roads. Hence a 20mph limit should not be surprising at all. May I therefore suggest that if you feel that you may well not notice such signs then you should assume that the speed limit is 20mph and only proceed faster if you have noticed a 30mph sign.
Rod King commented on Police Enforcement 2018-08-15 08:37:12 +0100Antony
There are no special arrangements for 20mph speeding offences. It is just like any other speeding offence.
Rod King commented on How local authorities can enforce 20mph limits 2018-08-19 17:44:24 +0100Hi Eddie
The HOTA requirements may be found at http://library.college.police.uk/docs/NPCC/NPCC-(2016)-Speed-Red-light-Enforcement-Technology-Guide-v1-2-1-July2016.pdf. I see no reason why these cannot be maintained.
It may be funded in many ways, including speed awareness courses.
Local authorities are well versed in complying with any competition acts.
I was delighted to be asked to speak at the seminar held in the Scottish Parliament building to discuss the private members bill for changing the national default limit for restricted roads in Scotland to 20mph. Local Authorities would be able to make appropriate exceptions where a 30mph limit would be retained for certain roads.
The text of my presentation follows :-Read more
Why Not Concentrate on ‘Special’ Locations for Road Safety?See all posts
Posted by Rod King · December 20, 2018 7:27 PM
Rod King published Bristol’s 20mph limits have led to valuable reductions in speed and casualties, and benefit active travel in Press Releases 2018-02-12 20:44:10 +0000
Bristol’s 20mph limits have led to valuable reductions in speed and casualties, and benefit active travel
The University of the West of England (UWE) has analysed the impact of 20mph roll-outs for Bristol City Council. It finds reductions of 2.7mph in average traffic speeds and an estimated cost saving of over £15m per year from fatal, serious and slight injuries avoided.Read more
Rod King commented on How Public Health Professionals Can Help Win 20mph Limits 2018-01-21 17:36:31 +0000Dear Cllr Davies
I am somewhat troubled by your suggestion that motorists who exceed speed limits are behaving “responsibly”. The whole point of local traffic authorities setting speed limits is that they warn drivers of risks and hazards which they may otherwise be unaware .
By all means you may have a different opinion on what speed limit to set, and as a councillor you have every opportunity to have your opinion heard, but once set then it becomes mandatory regardless of your opinion. Any driver deeming himself or herself above the law deserves any sentence that breaking such a law involves.
May I remind you of the long held principle in the UK that elected representatives of the people set laws, a professional police force enforces laws and an independent judiciary sentences those who are found breaking those laws.
Rod King commented on Get your info 2017-10-06 12:04:16 +0100Hi Carolyn
I have approached Professor Strauss regarding access to the paper.
Rod King commented on NICE Recommends 20mph limits Without Traffic Calming to Improve Air Quality 2017-07-29 18:48:43 +0100The most important thing is to be consistent. If you do something in only one place to physically reduce speeds then at the same time you are communicating that elsewhere you can and should go faster. Engineering is fine if you can do it throughout the whole network of community roads. But is the affordable or practical? Other routes to gain compliance can be engagement, enforcement. Society has a choice, carry on curbing walking and cycling from fear of traffic danger or subject non-compliers to the rule of law. Its not difficult, simply needs commitment to supporting communities and the levers to better public health, air quality, child and elderly mobility, etc.
Rod King commented on IAM are not so RoadSmart in their interpretation of the latest DFT report on speed limit compliance on 20mph roads 2017-07-03 18:34:04 +0100Other observations from the DfT report are that even on these roads with few visual clues as to the presence of people :-
1) On 20mph roads, 37% are exceeding the limit by less than 5 mph, which is not too bad
2) On 20mph roads, 15% are exceeding 30mph
3) On 30mph roads, 53% of cars are exceeding the 30mph (and 25% are going more than 35mph)
4) That means that roads with a 20mph limit have 38% FEWER cars going over 30mph!
Or to put it even more simply, while more than half of motorists exceed 30 mph on a 30 mph road, only 15% do on (even atypical, non residential) 20 mph roads, making them substantially safer for people walking or cycling.
P.S. If over half of all motorists are speeding on 30 mph roads does IAM conclude they’re causing confusion too?
Rod King commented on 20's Plenty for London Update - Sep 16 2017-05-31 19:12:02 +0100Dear James
Many thanks for your comments. We know from British Social Attitude Surveys that about 70% of people are in favour of 20mph limits for residential roads and busy streets. At the same time about 10% oppose. So I guess you are one of the 10%!
Yes, roads really are safer, and if you were to replace all the people using bicycles in Westminster with cars then it really would be far more congested.
And places which provide streets and roads which can be used by all rather than just those in cars are actually more economically successful than those with 20th century ideas of the car being king and used to displace other forms of transport.
Rod King commented on How we help 2019-06-02 16:13:54 +0100Hi Tanisha
For posting a sign to USA the postage is the major cost. But if you would like to donate $10 on our donate page at www.20splenty.org/donate then we will send you one.
Rod King commented on Lessons to learn from Manchester 2017-07-31 21:46:13 +0100Hi Vanessa
Our response is that driving more calmly and eliminating acceleration to 30mph will have a very positive effect on air quality. See our press releases
20MPH LIMITS OFFER A TOXIC DIESEL FUME REDUCTION EQUIVALENT TO TAKING HALF OF ALL PETROL CARS AWAY
NICE RECOMMENDS 20MPH LIMITS WITHOUT TRAFFIC CALMING TO IMPROVE AIR QUALITY