20mph speed limits - are they actually enforceable

Man of Honour
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I've always regarded "20 'zones'" as being "we'd really like you to do 20mph here, kthxbye" rather than actual 20mph limits.

A proper 20mph limit would be a red circle with 20 inside it. Most "20 'zones'" I've seen are a black circle with 20 in it, and the word "zone" underneath it - I see this as a recommendation rather than a rule.

That's because it is a recommendation. There are more and more actual limits now though, which are the 20 in a red circle.
 
Soldato
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Hit by a car at 20 mph, 1 out of 40 pedestrians will be killed. 97% will survive
Hit by a car at 30 mph, 2 out of 10 pedestrians will be killed. 80% will survive
Hit by a car at 35 mph, 5 out of 10 pedestrians will be killed. 50% will survive
Hit by a car at 40 mph, 9 out of 10 pedestrians will be killed. 10% will survive.
I doubt many people are hit by cars at those speeds. Cars have brakes, and these usually slow the vehicle before an impact. They should publish the data on average impact speeds in 30 limits along with this.
 
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Soldato
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They're going to introduce the 20 limit city wide in Cambridge, apart from a few key roads which will remain 30. My opinion is if it's needed, and the reasons are sound, it should be enforced everywhere within the city limits.

In reality, this isn't about safety or congestion. It's about votes from people who live next to busy roads.

A girl was killed on here bike on a road near me just before Christmas, the road will remain 30.
 
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Interesting facts about 20mph:

- They are usually used in residential calmed zones.
- Once you enter a 20mph zone (as indicated by signs at the entrance to the zone) repeater signs are not legally required. You cannot claim exemption because you "thought it was 30mph"
- With most speed limits anything up to 10% will generally not be prosecuted and there is a varying scale after this in England and Wales up to which you may be offered a chance to go to a speed awareness course instead of having a fine/points. With 20mph this is not the case - if you are caught exceeding 24mph it's automatic fine/points or summons (if you're above 35mph). In Scotland there is no speed awareness course option.
 
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I've always regarded "20 'zones'" as being "we'd really like you to do 20mph here, kthxbye" rather than actual 20mph limits.

A proper 20mph limit would be a red circle with 20 inside it. Most "20 'zones'" I've seen are a black circle with 20 in it, and the word "zone" underneath it - I see this as a recommendation rather than a rule.

Yep absolutely right. The 20 zone in Cambridge started out with the black circles, as a test I think, but quickly became official.
 
Soldato
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I doubt many people are hit by cars at those speeds. Cars have brakes, and these usually slow the vehicle before an impact. They should publish the data on average impact speeds in 30 limits along with this.

Yes but that would probably damage the ridiculous agenda that people in cars are all psychopathic nutters intent on killing poor pedestrians.

Roads are dangerous places to wonder around aimlessly, teaching kids that would probably be far more beneficial than any kind of speed limit reduction. The amount of complete morons that just wonder into the road completely oblivious to traffic is astounding, as we seem to be breeding a generation who believe that they have right of way as a pedestrian in any given situation on the roads.
 
Caporegime
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Yes but that would probably damage the ridiculous agenda that people in cars are all psychopathic nutters intent on killing poor pedestrians.

Roads are dangerous places to wonder around aimlessly, teaching kids that would probably be far more beneficial than any kind of speed limit reduction. The amount of complete morons that just wonder into the road completely oblivious to traffic is astounding, as we seem to be breeding a generation who believe that they have right of way as a pedestrian in any given situation on the roads.
Whilst it plays a large part, it isn't just limited to pedestrian idiocy though is it? Stopping distances are reduced the slower you go.
 
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There is a difference between a 20mph limit and a 20mph zone:

20mph limits are areas where the speed limit has been reduced to 20 mph but there are no physical measures to reduce vehicle speeds within the areas. Drivers are alerted to the speed limit with 20mph speed limit repeater signs (red circle). 20mph limits are most appropriate for roads where average speeds are already low, and the guidance suggests below 24mph. The layout and use of the road must also give the clear impression that a 20mph speed or below is the most appropriate.
20 mph zones use traffic calming measures to reduce the adverse impact of motor vehicles on built up areas. The principle is that the traffic calming slows vehicles down to speeds below the limit, and in this way the zone is becomes „self-enforcing‟. Speed humps, chicanes, road narrowing, planting and other measures can be introduced to both physically and visually reinforce the nature of the road. These are (sometimes) indicated by black bordered "advisory" signs.

In short, a 20 mph speed limit is legally enforceable (whether the Police do so or not is up to them), and a 20mph zone is not as it's designed to self-enforce.

If you want chapter and verse, the stuff quoted above was lifted from the ROSPA guide: http://www.rospa.com/roadsafety/advice/highway/info/20-mph-zone-factsheet.pdf
 
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Soldato
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IIRC speed limits are only advisory if they have a black rectangular border (usually has curved edges) or if they are variable LED ones on motorways and have no red ring around them (the advisory ones usually have amber lights).

Mandatory limits have red, black or blue rings (blue for minimum speed limit, these are very rare).

Circles give orders, Triangles give warnings, Rectangles give information and advice.
 
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Caporegime
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20mph... feels like such a crawl compared to 30.

After a few years of 20 will they say 15mph will be safer?

Or hopefully they will just ban large motorised vehicles from many small roads. Reduced pollution, reduced road deaths and fitter people. Win win... Oh no, you'll have to cycle to the town centre to get your big Mac and fries (or buy a small electric vehicle)...;)


Note I said small roads, not roads people commute along long distances...

There is nothing wrong with 20mph zones, just because the majority of motorists speed and insist they are the most important people on the roads doesn't mean it's correct... You knever know, slower speed limits may (read will) persuade more people to cycle and use the roads with other means of transport again.:D
 
Caporegime
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I guess one question is why are so many people (in this thread) happy to flaunt the law? If the law says 20mph, than why is it considered ok to do 30? You may not like the law, but that's a different matter and can be persued through different channels.
 
Caporegime
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but the further you travel the less impact acceleration and deceleration has on the final mph
most people wouldnt use their cars to go 100 meters

No, on average people travel 6 miles... With about half of all journeys less than 2 miles... If you don't like the 20mph limits then walk or cycle. ;)
 
Soldato
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I know round my area, all the 20's are where there's loads of kids. Near schools, and on one tin house estate where the kids are all thick as pig****.
 
Caporegime
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Around here we have 20 limits by schools, which is sort of circular logic as children getting hit outside schools doesn't really have anything to do with speed, the problem is children are stupid as **** and believe they cannot die so walk/run out in front of cars, fencing the pavement off apart from a designated crossing would be a much better solution to the problem.

On a lsightly related note I do sometimes wonder how many people have been hit by cars because the drivers didn't see them step off the curb as they were so focused on their speedo and/or lining up for a speed hump, the more we try to make things safer the more dangerous they become.
Or alternatively car drivers speed through the streets , swerve onto new roads at junctions and almost run over a pedestrian because they didn't indicate or didn't look before turning into the new road... Happens way too often. Just because you are in a car doesn't mean you rule the road, pedestrians have right of way and priority over you, cyclists have right of way and priority over you and so do horse riders..;)
 
Soldato
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So Bristol have today "unveiled" a bunch of new areas that now have a 20mph speed limit.

I thought (ironically I learnt this at speed school :D ) that these were not legally enforceable as that would require the government to change the law. I was told by the people running the course that they were a guideline, and as long as you stuck to 30mph (which is the national speed limit) then the police can't do you for speeding. That's why the signs are smaller in size for example, because if they were the same size as 30mph ones, then the signs would be illegal.

I remember them saying something along the lines of "if you had a crash, they might be able to charge you with dangerous driving if they believed that to be the case, but that as long as you were within 30mph, then they couldn't charge you for speeding."


Does anyone have definitive proof of what the law says? They make it sound like we HAVE to stick to the speed limit, so most people take that as gospel and do, but is it actually the law?

Thanks for anyone's help :)

I remember Edinburgh, that well known anti-car city, putting 20mph limits throughout the city and the next summer they discovered that pollution levels had increased. There was apparently "shock horror" statements from council members. Anyone who drives a car knows that it is not working efficiently at 20mph but this simple fact seems to have bypassed the City Council.
To show they have learned their lesson they are going to put in 20mph limits in the south of the city.

As stated elsewhere any speed limit is backed by law.

As to the car crash question, the charge would probably read 'driving without due care and attention' if you were driving at 30mph.
 
Soldato
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Or alternatively car drivers speed through the streets , swerve onto new roads at junctions and almost run over a pedestrian because they didn't indicate or didn't look before turning into the new road... Happens way too often. Just because you are in a car doesn't mean you rule the road, pedestrians have right of way and priority over you, cyclists have right of way and priority over you and so do horse riders..;)

I really don't see how this is related to my post, I wasn't suggesting that people should drive like that or that cars are more important than any other road users :confused:
 
Caporegime
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I really don't see how this is related to my post, I wasn't suggesting that people should drive like that or that cars are more important than any other road users :confused:

Because you seem to be insisting that it's mainly the pedestrians fault for being run over whereas there are a mountain of drivers breaking the law and/or driving dangerously causing accidents. Reduce the speed limit and you hopefully reduce the speed of the speeders (especially if they are actually enforced), that'll hopefully reduce the chance of death or accident if either driver or pedestrian make a mistake or aren't as observant as they should be.

Tbh this thread just stinks of motorists complaining they should be able to speed and pedestrians should just stay away. Luckily the laws, regulations and authorities seem to be aiming towards removing cars from roads in towns, which should be lauded. It makes little difference to people the commute long distances and reduces the likelihood of death. The only people it really afford cya are those that trave short distances (through residential areas), who I have no sympathy for. Walk, cycle of get a small electric vehicle ...
 
Soldato
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Because you seem to be insisting that it's mainly the pedestrians fault for being run over

I see, I think you misunderstood, my point was that children getting hit by cars outside of schools is not a speed/driver issue it is a children issue, drivers already pay extra care by schools and usually drive slower, because it's common knowledge that children are stupid/fearless/reckless (we all know this because we used to be them).

Reducing the speed limit near schools doesn't reduce accidents it merely means when a child comes bombing out of the gates into the road they get hit slower which reduces the damage caused, in theory it sounds good but a much better solution would be to put fences in front of the foot gates to stop them doing it and force them to cross at set points (luckily a number of schools are doing this).

And also it would help to better educate them about the dangers of the road, stepping out from behind parked cars, not looking/listening properly, etc as this has really gone down hill since the "old days".
 
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