Blanket 20mph limit across Wales from 2023
Discussion
Evanivitch said:
ITP said:
Maybe it should be 10mph then. That must be even safer, show us a graph of that, some total muppets will have done one im sure.
Have you heard of pedestrian zones? Perhaps you don't leave the house much.To be clear, I have no problem with 20mph in specific areas. I live in a ‘bustling’ suburban village, 20 is more than enough where all the shops/bars are, and virtually everyone travels at that speed or slower, as it is common sense, even though the official limit is 30. Plus, very few people, if any, drive past the local school at drop off pick up at 30. Again, common sense.
What is stupid is blanket 20 limits that are currently 30, EVERYWHERE. I’d say that will cause more accidents as peoples common sense kicks in and they start overtaking people doing 18 in what are clearly perfectly safe areas to do 30, which all get dragged into a blanket 20 limit. And using environmental reasons is just daft, as people will drive in a lower gear, increasing emissions and noise, no matter what a theoretical study says. Until everyone is forced into gps controlled EV’s of course…..
bigothunter said:
Evidence shows that 20mph limits increase pollution and fuel consumption. I've posted data to support that assertion.
Incorrect. You've provided evidence that travelling at 20 mph is less efficient than 30 mph.But cars do not travel consistently at either speed in areas where these speed limits are applied. It is the acceleration (higher engine load) to the limit and subsequent deceleration (brake dust) that is the main cause of vehicle pollution in urban areas.
Yet again, you've made false assumptions and been found lacking.
ITP said:
Pedestrian zones? Why are you even comparing that. Pedestrian zones are clearly areas for pedestrians, the clue is in the name.
Because it's a simple example that there are have been streets for decades where vehicles do not have priority (but still have access) and that they must travel at speeds significantly less than 20 mph.This includes many car parks, commercially operated sites and service stations with 5/10 mph speed limits.
ITP said:
To be clear, I have no problem with 20mph in specific areas. I live in a ‘bustling’ suburban village, 20 is more than enough where all the shops/bars are, and virtually everyone travels at that speed or slower, as it is common sense, even though the official limit is 30. Plus, very few people, if any, drive past the local school at drop off pick up at 30. Again, common sense.
Yes absolutely agree 
ITP said:
What is stupid is blanket 20 limits that are currently 30, EVERYWHERE. I’d say that will cause more accidents as peoples common sense kicks in and they start overtaking people doing 18 in what are clearly perfectly safe areas to do 30, which all get dragged into a blanket 20 limit. And using environmental reasons is just daft, as people will drive in a lower gear, increasing emissions and noise, no matter what a theoretical study says. Until everyone is forced into gps controlled EV’s of course…..
Lower speeds increase emissions and energy consumption (eg fuel burnt) in theory and practice, even for EVs. Denial of that fact is just dogma.Reason is simple. At low speeds, parasitic losses (eg air conditioning) dominate over road load. With ICE at 20mph, that's exacerbated by the engine operating in an even less efficient zone of the BSFC map.
So emissions and fuel consumption become predominantly time-based not distance-based. A journey taking 50% more time (at 20 rather than 30mph) will be more environmentally harmful.
Evanivitch said:
bigothunter said:
Evidence shows that 20mph limits increase pollution and fuel consumption. I've posted data to support that assertion.
Incorrect. You've provided evidence that travelling at 20 mph is less efficient than 30 mph.But cars do not travel consistently at either speed in areas where these speed limits are applied. It is the acceleration (higher engine load) to the limit and subsequent deceleration (brake dust) that is the main cause of vehicle pollution in urban areas.
Yet again, you've made false assumptions and been found lacking.
Evanivitch said:
ITP said:
Pedestrian zones? Why are you even comparing that. Pedestrian zones are clearly areas for pedestrians, the clue is in the name.
Because it's a simple example that there are have been streets for decades where vehicles do not have priority (but still have access) and that they must travel at speeds significantly less than 20 mph.This includes many car parks, commercially operated sites and service stations with 5/10 mph speed limits.
Are you suggesting that because the speed limit in tescos car park or an oil terminal access road is not 30, people should be used to driving in that scenario, and therefore ALL roads with a 30 limit should now be converted to being a pedestrian area, and hence limits reduced as pedestrians now have no need for personal responsibility for their safety?
I don’t see what’s wrong with the system we have where pedestrians have things called pavements, where they are safe, and the cars use the roads in between the pavements. And when pedestrians want to cross to the other side they either use a designated crossing, or use their eyes, god forbid, and not step out in front of a moving vehicle.
But it seems now personal responsibility for your own safety is somehow now a ridiculous concept. But I’m just an old dinosaur, my views are outdated I’m sure. The ‘data’ proves me wrong it seems.
I just put the cat amongst the pigeons on my village face book group.
The road between my village and the next is currently 40mph, one person complained about someone speeding, so the local parish council want to put in traffic calming and reduce the limit to 30mph.
It was pointed out the them that their own figures show speeding on that road is really not a problem, just 0.09% were over the limit the last time they did the traffic survey back in 2018.
Local councillor is still very keen to reduce the limit etc, and traffic monitoring wires have just appeared on the road.
I've just pointed out that if she gets her way and reduces the limit to 30, next September it will automatically reduce to 20 under the new law.
Cue lot of fuss and not happy locals!
The road between my village and the next is currently 40mph, one person complained about someone speeding, so the local parish council want to put in traffic calming and reduce the limit to 30mph.
It was pointed out the them that their own figures show speeding on that road is really not a problem, just 0.09% were over the limit the last time they did the traffic survey back in 2018.
Local councillor is still very keen to reduce the limit etc, and traffic monitoring wires have just appeared on the road.
I've just pointed out that if she gets her way and reduces the limit to 30, next September it will automatically reduce to 20 under the new law.
Cue lot of fuss and not happy locals!
eccles said:
I just put the cat amongst the pigeons on my village face book group.
The road between my village and the next is currently 40mph, one person complained about someone speeding, so the local parish council want to put in traffic calming and reduce the limit to 30mph.
It was pointed out the them that their own figures show speeding on that road is really not a problem, just 0.09% were over the limit the last time they did the traffic survey back in 2018.
Local councillor is still very keen to reduce the limit etc, and traffic monitoring wires have just appeared on the road.
I've just pointed out that if she gets her way and reduces the limit to 30, next September it will automatically reduce to 20 under the new law.
Cue lot of fuss and not happy locals!
Twenty's plenty The road between my village and the next is currently 40mph, one person complained about someone speeding, so the local parish council want to put in traffic calming and reduce the limit to 30mph.
It was pointed out the them that their own figures show speeding on that road is really not a problem, just 0.09% were over the limit the last time they did the traffic survey back in 2018.
Local councillor is still very keen to reduce the limit etc, and traffic monitoring wires have just appeared on the road.
I've just pointed out that if she gets her way and reduces the limit to 30, next September it will automatically reduce to 20 under the new law.
Cue lot of fuss and not happy locals!
nb sarcasm
My view on appropriate 20mph sections of road is that most sensible drivers would be driving at that speed anyway, with or without the imposed limit, and that any new/reduced speed limit will never stop dicks driving like dicks. If when a new speed limit has been introduced the average speed of traffic flow is still above that limit then it is likely that the limit is inappropriate and should be reconsidered.
I'd be happy to see more 20mph zones in built up areas if limits on motorways would also be reconsidered and raised to 80mph where appropriate.
I'd be happy to see more 20mph zones in built up areas if limits on motorways would also be reconsidered and raised to 80mph where appropriate.
bigothunter said:
Evanivitch said:
bigothunter said:
Evidence shows that 20mph limits increase pollution and fuel consumption. I've posted data to support that assertion.
Incorrect. You've provided evidence that travelling at 20 mph is less efficient than 30 mph.But cars do not travel consistently at either speed in areas where these speed limits are applied. It is the acceleration (higher engine load) to the limit and subsequent deceleration (brake dust) that is the main cause of vehicle pollution in urban areas.
Yet again, you've made false assumptions and been found lacking.
Honestly, if you're going to accuse me of conjecture for the most basic information it's not even worth my time linking to it.Evanivitch said:
bigothunter said:
Evanivitch said:
bigothunter said:
Evidence shows that 20mph limits increase pollution and fuel consumption. I've posted data to support that assertion.
Incorrect. You've provided evidence that travelling at 20 mph is less efficient than 30 mph.But cars do not travel consistently at either speed in areas where these speed limits are applied. It is the acceleration (higher engine load) to the limit and subsequent deceleration (brake dust) that is the main cause of vehicle pollution in urban areas.
Yet again, you've made false assumptions and been found lacking.
Honestly, if you're going to accuse me of conjecture for the most basic information it's not even worth my time linking to it.
Evanivitch said:
But cars do not travel consistently at either speed in areas where these speed limits are applied. It is the acceleration (higher engine load) to the limit and subsequent deceleration (brake dust) that is the main cause of vehicle pollution in urban areas.
On which drive cycle is your statement based? NEDC or WLTP perhaps? Or does it simply lack any scientific rigour?JMBMWM5 said:
wyson said:
Loads of 20mph limits in London. Generally, I think they are completely fair and I stick to them. My old road was a 20mph road. It had a single width space down the middle, cars parked on both sides with limited visibility. Would have no chance of seeing a kid if they decided to run out between parked cars. There was also very limited visibility at junctions too. Had to stop a fair few times because cars popped out blind. They would only have been able to see me once they came out onto the road, especially with a van or SUV parked near the junction.
TBF, I have seen 20mph roads with amazing visibility, speed humped etc measures that were probably implemented because they were used as rat runs and cars sped down them during rush hour.
In London at least, the majority of 20mph zones, I found myself driving down them 20mph to 25mph. 30mph would have been too fast so I can understand councils taking precautionary measures by implementing 20mph zones.
LOL, I drive in London on 20 MPH roads and no one does 20 MPH it's more like 30, pathetic draconian speed limits. TBF, I have seen 20mph roads with amazing visibility, speed humped etc measures that were probably implemented because they were used as rat runs and cars sped down them during rush hour.
In London at least, the majority of 20mph zones, I found myself driving down them 20mph to 25mph. 30mph would have been too fast so I can understand councils taking precautionary measures by implementing 20mph zones.
Edited by wyson on Sunday 20th March 10:52
Evanivitch said:
bigothunter said:
Evanivitch said:
bigothunter said:
Evidence shows that 20mph limits increase pollution and fuel consumption. I've posted data to support that assertion.
Incorrect. You've provided evidence that travelling at 20 mph is less efficient than 30 mph.But cars do not travel consistently at either speed in areas where these speed limits are applied. It is the acceleration (higher engine load) to the limit and subsequent deceleration (brake dust) that is the main cause of vehicle pollution in urban areas.
Yet again, you've made false assumptions and been found lacking.
Honestly, if you're going to accuse me of conjecture for the most basic information it's not even worth my time linking to it.ingenieur said:
I've done that as well. People overtake if the car in front is driving inappropriately. You get some absolute helmets driving at 18mph on roads that at one time might have even been as fast as 60mph in the 1990s. Clearly the road is designed for much higher speeds and it would be safe to drive faster. So overtaking a cabbage... who is probably wearing a face mask alone inside his car is what all the drivers do as soon as they get the chance.
But assuming you mean 20mph zones, you would be breaking the law. Many PH contributors consider that alone to be morally outrageous. Clearly you are open to prosecution too. If an accident occurred, your illegal speed would be cited as the major reason almost regardless of circumstances.bigothunter said:
ingenieur said:
I've done that as well. People overtake if the car in front is driving inappropriately. You get some absolute helmets driving at 18mph on roads that at one time might have even been as fast as 60mph in the 1990s. Clearly the road is designed for much higher speeds and it would be safe to drive faster. So overtaking a cabbage... who is probably wearing a face mask alone inside his car is what all the drivers do as soon as they get the chance.
But assuming you mean 20mph zones, you would be breaking the law. Many PH contributors consider that alone to be morally outrageous. Clearly you are open to prosecution too. If an accident occurred, your illegal speed would be cited as the major reason almost regardless of circumstances.There is a certain sense in many people that if a rule becomes absurd that you just ignore it. That's the danger with this scheme from the
s in Cardiff. In Bayswater Road and Park Lane, London there are digital cameras enforcing this limit; trunk roads which were previously 40 mph. The black cab cohort are not happy as numbers of them have been caught doing 26 to 28 mph. Park Lane northbound (now down to a single 20 mph lane) has also been given a wide cycle lane despite the fact that there is a parallel cycle path in the park, just the other side of the fence.
Furthermore the ease of traffic circulation around the complex junction at Lancaster Gate, so finely tuned over many years, has been totally destroyed. Driving in central London is pure misery now, with the constant threat of a relatively trivial infraction resulting in 3 points, even in empty streets at 2.00 am. I'm sure Sadiq Khan feels much safer in the back of his chauffeur driven Range Rover.
Furthermore the ease of traffic circulation around the complex junction at Lancaster Gate, so finely tuned over many years, has been totally destroyed. Driving in central London is pure misery now, with the constant threat of a relatively trivial infraction resulting in 3 points, even in empty streets at 2.00 am. I'm sure Sadiq Khan feels much safer in the back of his chauffeur driven Range Rover.
runnerbean 14 said:
In Bayswater Road and Park Lane, London there are digital cameras enforcing this limit; trunk roads which were previously 40 mph. The black cab cohort are not happy as numbers of them have been caught doing 26 to 28 mph. Park Lane northbound (now down to a single 20 mph lane) has also been given a wide cycle lane despite the fact that there is a parallel cycle path in the park, just the other side of the fence.
Furthermore the ease of traffic circulation around the complex junction at Lancaster Gate, so finely tuned over many years, has been totally destroyed. Driving in central London is pure misery now, with the constant threat of a relatively trivial infraction resulting in 3 points, even in empty streets at 2.00 am. I'm sure Sadiq Khan feels much safer in the back of his chauffeur driven Range Rover.
The very point - driving in London is intended to be pure misery now. Cars, motorbikes, vans and even trucks are simply unwelcome...Furthermore the ease of traffic circulation around the complex junction at Lancaster Gate, so finely tuned over many years, has been totally destroyed. Driving in central London is pure misery now, with the constant threat of a relatively trivial infraction resulting in 3 points, even in empty streets at 2.00 am. I'm sure Sadiq Khan feels much safer in the back of his chauffeur driven Range Rover.
ingenieur said:
I've done that as well. People overtake if the car in front is driving inappropriately. You get some absolute helmets driving at 18mph on roads that at one time might have even been as fast as 60mph in the 1990s. Clearly the road is designed for much higher speeds and it would be safe to drive faster. So overtaking a cabbage... who is probably wearing a face mask alone inside his car is what all the drivers do as soon as they get the chance.
Irony is those you call 'helmets driving at 18mph' are those obeying the law with just 2mph margin. Seems the law has made helmets of us all now.There is another side to this. Try driving rigidly to their inappropriate 20 limits especially when the road is uncongested. Those stuck behind go f
king apest with frustration and small motorbikes whizz past often over pedestrian crossings. Even fast cyclists overtake.Admittedly perverse but great fun. And all in the cause of law abidance
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