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About the 20mph speed limit in Wales built up areas? Which goes live tonight..

I wonder if the police will run lots of speed checks Monday? It would make sense to show early commitment to the new rules.

I heard on the radio that whatever enforcement there is will be (for X period of time) that anything over 30 will be instant ticket, but between 20 and 30 will be education, not SAC's, but a chat, short video etc...

From what I've read, none of the automatic enforcement stuff - speed cameras - have been changed to 20 yet, I think (apart from the VSL's on motorways) it's all manual changing required.

I doubt there'll be any prosecutions until all the speed limit signs have been changed - which isn't going to be quick.

It'll be interesting to see firstly how quickly, and to what extent speed, and accidents, change, and secondly how long it takes the machinery - signage and enforcement - to change.
 
Should we do some Newtonian physics on that one?

85 kg + 25 kg = 110 kg mass

Velocity = 25 mph (let's keep this metric and call that 40 kmh - very fucking fast and e-bikes in London don't regularly do 40 kmh in London. That's simply not true. but let's take like it is true)

That's an energy of 1/2 x 110 x 40^2 = 88,000 units

A small car obeying London's lower speed limit and doing 30 kmh, let's say it weighs 1,000 kg with its occupants

That's an energy of 1/2 x 1,000 x 30^2 = 450,000 units

So the small car has roughly five times the kinetic energy of the cyclist even going at the slower speed.

It's not all about kinetic energy though is it? If it was, a person hit by a 360-tonne train at 50mph would stand a better chance of surviving than one hit by a 720-tonne train at 50mph.

People do survive being hit by 50mph trains, usually if they're dealt a glancing blow. It follows that the profile of the front end is perhaps more important than the amount of kinetic energy in such situations. This is just one example.
 
I heard on the radio that whatever enforcement there is will be (for X period of time) that anything over 30 will be instant ticket, but between 20 and 30 will be education, not SAC's, but a chat, short video etc...

From what I've read, none of the automatic enforcement stuff - speed cameras - have been changed to 20 yet, I think (apart from the VSL's on motorways) it's all manual changing required.

I doubt there'll be any prosecutions until all the speed limit signs have been changed - which isn't going to be quick.

It'll be interesting to see firstly how quickly, and to what extent speed, and accidents, change, and secondly how long it takes the machinery - signage and enforcement - to change.
In Wandsworth, the fines started from day 1 for anyone exceeding 30 MPH ( as my colleagues will testify). There are still many drivers who drive around at 30 ish
in 20 limits and will try and intimidate you or give you grief if you stick to 20.
 
In Wandsworth, the fines started from day 1 for anyone exceeding 30 MPH ( as my colleagues will testify). There are still many drivers who drive around at 30 ish
in 20 limits and will try and intimidate you or give you grief if you stick to 20.

Has the signage changed?
 
Has the signage changed?
Signs are not needed. 20mph will be the default in any road in a "built up" area (which means it has street lights a certain distance apart from each other, not buildings as you might expect it to mean) and which doesn't have any signs with another limit on them (which overides the default). I'm sure they will update signs though.

Edit -in wales not england where built up default still 30mph. (Sorry realised you talking about london)
 
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Signs are not needed. 20mph will be the default in any road in a "built up" area (which means it has street lights a certain distance apart from each other, not buildings as you might expect it to mean) and which doesn't have any signs with another limit on them (which overides the default). I'm sure they will update signs though.

Edit -in wales not england where built up default still 30mph. (Sorry realised you talking about london)

Signs will be needed at the end of faster limits, for example entering a built up area from a country road there will be existing 30 signs that need changing. There won't be any need for repeater signs though.
 
I would think that any 30 sign will need to be replaced - difficult to imagine any prosecution succeeding for a <30 (and they'll have to start enforcing it eventually) offence if the driver can show that the road was clearly marked as a 30mph limit.
 
I would think that any 30 sign will need to be replaced - difficult to imagine any prosecution succeeding for a <30 (and they'll have to start enforcing it eventually) offence if the driver can show that the road was clearly marked as a 30mph limit.
If there is a 30mph sign then its 30mph. Though i'm sure they will change them to 20mph eventually.
 
I would think that any 30 sign will need to be replaced - difficult to imagine any prosecution succeeding for a <30 (and they'll have to start enforcing it eventually) offence if the driver can show that the road was clearly marked as a 30mph limit.

Correct. They can't prosecute without adequate signage. In London it's been changed to 20 on both the repeater signs and road markings. They haven't noticeably inreased the number of cameras (although Khan says otherwise) so they've only recalibrated the old 30mph units, which stand out like bulldogs bollocks. As ever, the issue is enforcement. All locals know exactly where the cameras are, they're fucking big yellow boxes with warning signs preceeding them, and nowadays all navigation apps give you 300 meters warning of them anyway. Waze even tells you if there's a solo copper having a sandwich in a layby ahead of you. You've got to be pretty dim to get done by one of them.

The reality is that there are many roads where 20mph is pefectly appropriate (residential streets in genuinely built-up areas) but most people did 20 on those anyway. There are roads near us which are effectively dual carriageways with 20 limits now, so they are roundly ignored, even by the police. Very few people pay them much heed beyond slowing down a bit for the cameras then getting on their way again as soon as they cross the grad marks.
 
I am pretty sure the speed limit will apply to bicycles and scooters.

It is a limit for road users, not just motorists.

There are no speed limits in the highway code for bikes, e-bikes, push scooters or pedestrians. The speed limits are specified by vehicle type and only motor vehicles are specified. e-scooters I'm not sure about tbh, I think that it's never come to court so not been legally defined but they probably count as a moped? They are mechanically propelled but there's no type class for them. It's kind of a moot point since only the rental ones are legal to use on the roads and they are limited to 15mph which is lower than any normal speed limit.

e-scooters might get specifically included once they get legislated for, depends if they are legally limited to 15mph or not. Obviously if they are limited to 15mph there's no need to have them included in the speed limit table. Anyone using an illegal escooter to go faster than the speed limit is likely to be facing much more serious charges than speeding should police decide to use their limited resources to enforce the law instead of policing more dangerous vehicles.

cyclists who are exceeding speed limits could be charged with a general careless or dangerous cycling charge, but not with speeding.
 
The reality is that there are many roads where 20mph is pefectly appropriate (residential streets in genuinely built-up areas) but most people did 20 on those anyway. There are roads near us which are effectively dual carriageways with 20 limits now, so they are roundly ignored, even by the police. Very few people pay them much heed beyond slowing down a bit for the cameras then getting on their way again as soon as they cross the grad marks.
it really is time we followed France and made it illegal for a satnav device to show camera positions. It could be done overnight with a few lines of code.

Then stop painting cameras yellow. Hide them all as much as possible.
 
it really is time we followed France and made it illegal for a satnav device to show camera positions. It could be done overnight with a few lines of code.

Then stop painting cameras yellow. Hide them all as much as possible.
They were originally painted grey, I'm not sure but I think it was the result of some legal challenge that ended up with them being repainted yellow
 
I'm guessing people who ignored limits before will continue to ignore them. Those that stuck to limits before will obey the new one.
They should change the law to make speeding an offence punishable by having to remove stuck on chewing gum from pavements with their tongue. That might deter some idiot drivers.
 
Iirc it was that the law that authorised fixed cameras stated that they were for safety, with the intention of getting drivers to reduce speed down to/below the limit, not primarily as a method of enforcement of the speed limit.
 
I've been googling it, it seems they were repainted in 2015 due to a change in the law. The reason given was improving safety since drivers were not spotting them to the last moment and were then hitting the brakes suddenly
Quite often there are seemingly counter intuitive reasons that things just work better. Like the merging at a bottle neck thing: it’s actually better for flow that some people merge late.

So if it turns out that actually having hi vis cameras means people are driving slowly without hard braking at the high accident spots (and I don’t know if this is correct, I’m just postulating), then we should go with that. Crowd behaviour isn’t always what you’d expect.

But I’m in favour of a default 20 in build up areas, and people will soon get used to it.

As noted before, though, these measures shouldn’t be in isolation, but be accompanied by initiatives to make public transport more attractive, cheaper (ideally free), easier to access, and with more coverage.
 
I've been googling it, it seems they were repainted in 2015 due to a change in the law. The reason given was improving safety since drivers were not spotting them to the last moment and were then hitting the brakes suddenly
:facepalm:
 
The Council Highways gangs have been out this morning in my part of Pembrokeshire swapping the 30mph signs to 20s. Most of them had been done by the time I drove to a local supermarket.

It will take a while to get used to after decades of driving at 30 in towns/villages. I had to keep brain engaged and it felt very slow and ‘wrong’ to be chugging along at 20 (our urban roads aren’t that busy most of the time) but it’ll come.
 
..
cyclists who are exceeding speed limits could be charged with a general careless or dangerous cycling charge, but not with speeding.
If cyclists are not expected to obey speed limits I expect it was because 30 was the lowest limit and few if any cyclists can achieve 30, even downhill with the wind behind

Now with a 20 limit I expect the code will be modified to include cyclists where speed limits are concerned (if indeed they are excluded at the moment) after all we expect cyclists to obey traffic lights and give way rules so it would be most strange if they were excluded from speed limits.
 
If it needs spelling out:

Speed was a factor in 48% of fatal collisions in London in 2020.
Collision data from around the world is very clear. It shows that the faster a vehicle is travelling:
  • The more likely a collision will occur because the driver has less time to react, stop or avoid the collision
  • The more severe an injury resulting from the collision will be
This is why we're lowering speed limits across London.

Changes to speed limits​

We're lowering speed limits because if you hit someone at 30mph they're five times more likely to die than if you hit them at 20mph.

Why do you think speed is such a factor in London with this 48% when across the country it's 19% or 25%, according to an article you've already posted?
 
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