If you are from the media and creating an article on implementing 20mph or on 20's Plenty For Us, then we hope that this page will give you some of the information that will help.
First a few useful facts :-
History: The 30 mph default urban speed limit dates to 1934 when there were fewer than 2 million motor vehicles. There are over 33m today. 20’s Plenty for Us, the national campaign for a 20 mph default speed limit where people live, was founded in autumn 2007 by Rod King. See www.20splentyforus.org.uk
As of August 2014, over 12 million people live in UK authorities who have implemented, or are committed to adopt, a 20mph default limit in residential areas. These include Portsmouth, Oxford, Bristol, Newcastle, Warrington, Sheffield, York, Middlesbrough, Edinburgh, Liverpool, Brighton & Hove, Sefton, Leicester, Cambridge, Coventry, Bath & NE Somerset, Darlington, Wigan, Dunbar, Rochdale, Otley, Shipley, Bury, Bolton, Nottingham, City of Manchester, City of Birmingham, Calderdale, the County of Lancashire, together with the London Boroughs of Hackney, Islington, Camden, Waltham Forest, Greenwich, Lewisham, Haringey, Lambeth and the City of London. 20’s Plenty for Us support over 240 local campaign groups pressing for change in their city, town or village’s road speed.
Our call is that whilst we used to have blanket 30mph limit in urban and village areas with only a few exceptions where the limit was set lower, this should now be changed to a "default 20mph limit" and exceptions made where it is appropriate. This matches a developing social consensus that for residential roads, high streets, and around places where people work, shop or learn then the maximum speed of motor vehicles should be limited to 20mph unless specific provision is made to accommodate higher speeds without prejudicing the safety of vulnerable road users.
Limits or Zones: There used to be a very clear distinction between areas or roads set as 20mph zones or 20mph limits. 20mph zones require any point to be within 50m of a "traffic calming device" which used to be defined quite strictly as a physical calming device. Whilst 20mph limits only require each point to be within 50m of a repeater sign that informed the driver that the speed limit was 20mph.
This reliance on largely physical calming in zones increased the cost some 50-fold over limits due to the expense of such physical calming. Hence for the same cost of treating a street of 250 people with a physically calmed zone then an entire community of 12,500 could be treated with a wide-area 20mph limit.
However this requirement was relaxed in 2011 when the DfT announced that for 20mph zones then repeater signs, carriageway roundels and mini-roundabouts could also be classed as "traffic calming devices". However any zone should include at least one physical calming device. In limits a carriageway roundel could also be used in place of a repeater sign.
This has made a huge difference to the way that 20mph limits may be set and in practice there may be little difference between zones and limits. Where traffic authorities are implementing 20mph limits the choice of zone or limit will probably depend on the type of street, current vehicle speeds and whether isolated 20mph zones already exist. If they do then it is often more practical to widen expand these in a much larger community-wide zone. Note that 20mph zones have rectangular boundary signs with a 20mph limit sign within it, whereas 20mph limits have round boundary signs.
In order to set a 20mph limit, either as a zone or limit, then the following conditions must apply :-
1) The correct Traffic Regulation Order must be made for the road concerned.
2) Any signage or traffic calming devices (in the case of zones) must meet the Traffic Signs Regulations and General Directions. This specifies the design of signs or traffic calming devices and where they need to be placed.
Once this has been done then such 20mph limit or zone is valid and enforceable by the police. The Association of Chief Police Officers have guidance on this which is available here.
The DEpt for Transport guidance on setting local speed limits was revised in 2013 and this very much encourages the use of 20mph limits or zones for residential streets and those with high numbers (or potential numbers) of cyclists and pedestrians. This is available here.
Note that the TSRGD is a technical document that must be adhered to, whereas the DfT and ACPO documents are guidance.
Also note that some of our earlier 20's Plenty for Us documents may well presume that 20mph zones require physical calming as was the case. Where we do refer to "zones" being more expensive than limits then this is only if largely physical traffic calming is used rather than the current options to use repeater signs and roundels instead.
Benefits of 20 mph Limits: Better safety, financial savings, cuts danger by 95% to walkers and cyclists, quieter, better air quality, increases walking and cycling, better health, less congestion, raises property values and a higher footfall increases shop takings. These are increasingly being noted by the Public Health departments of local authorities.
Popularity: A British Social Attitudes Survey conducted annually over the last 10 yeas consistently found 75% support 20 mph limits in residential areas, including 72% of drivers (2010 British Social Attitudes Survey – Attitudes to transport ).
Busting the Myths. We have a Briefing Sheet on this here
Images: And here are some pictures of typical 20 mph speed limited streets in Portsmouth :-
Click on images to enlarge
And here is a picture of a 20 mph speed limit on the main A61 in Thirsk
You may use the pictures, but please attribute them to 20's Plenty For Us.
and of course if you need any further information then please email or telephone us.