It's worth noting that injury and fatalies on German motorways are already higher than the UK on limited sections to start with and significantly higher (more than 20% higher) on unlimited stretches (and that's based on per million km driven, so its a fair comparator). This idea that autobahns are safer than UK motorways is a myth.
Looking at older vehicles nowadays I think you could argue that 70mph was recklessly high then for most vehicles.

Only if you look at the tailpipe of one car (which is probably ULEZ compliant anyway). Tyre particulates increase with speed. Lowering speed limits smooths out traffic flow which reduces wasteful idling. Making it safer to walk/cycle will reduce the number of cars on the road and therefore reduce pollution.Meanwhile, whilst driving in a long 20mph zone yesterday, I noted the decrease in mpg compared to the adjacent 30mph .. that is *increasing* pollution....
That is a fit car though!Probably true, yes. My Dad used to have an MGB* and 70 in that was scary, and that was a sports car, not a typical family saloon!
* Not the "car with the most letters", the BL MG MGB GT V8, but rather a straight six soft top![]()
The amount of opposition round my way to a relatively short segregated cycle lane with no reduction in the number of main carriageway lanes reaffirms my view that the UK has a long way to go on safe walking and cycling infrastructure.Only if you look at the tailpipe of one car (which is probably ULEZ compliant anyway). Tyre particulates increase with speed. Lowering speed limits smooths out traffic flow which reduces wasteful idling. Making it safer to walk/cycle will reduce the number of cars on the road and therefore reduce pollution.
Which would put them at 80.7783mph?They absolutely aren't and I'm not sure anyone claimed they were. Lane discipline is certainly better, but the huge speed differentials on what are often 2 lanes each way roads are downright dangerous.
It's long overdue to slap a 130km/h limit on them (basically the European standard) and I reckon with Germany being so environmentally aware you might just get away with it now on those grounds, though you wouldn't have done 20 years ago.
Vertical deflection (e.g. speed bumps, humps, rumble strips, etc) is shown to be (slightly) more effective than cameras in changing driver speed.Which would put them at 80.7783mph?
Of course we need to understand the tyre particulate speed effect rather than tail emissions under the transition to electric cars.
This analysis of the impact of 20mph in London suggests no effect on tail emissions and that the reduction of tyre particulates was achieved because of fewer accelerations and decelerations versus 30mph roads.
However, if we are targeting pollution, then speed bumps need to go, as they significantly increase both tyre particulate and tailpipe emissions. Strong argument in favour of cameras there.
Which would put them at 80.7783mph?
Of course we need to understand the tyre particulate speed effect rather than tail emissions under the transition to electric cars.
The problem is that anything which promotes speed change increases pollution. Therefore, you need something which will avoid interfering with traffic flow. In many cases parked cars do the job. Where smooth flow is anticipated, then average speed cameras work to prevent slowing to pass the cameras themselves.Vertical deflection (e.g. speed bumps, humps, rumble strips, etc) is shown to be (slightly) more effective than cameras in changing driver speed.
I would normally agree that cameras are better than speed bumps for a few reasons, but there's a trend recently of people smashing up speed cameras, burning them, bagging them, etc. It takes a lot more effort to remove speed bumps, they're cheaper to replace, and they don't face quite as much opposition from the, "speed cameras are just a cash cow", crew.
Indeed, which is why 20mph (usually) works out quite well because it smooths out the stop-start. I've been in favour of camera enforcement if we could sort out the criminal damage issue from 'Bladerunners'.The problem is that anything which promotes speed change increases pollution. Therefore, you need something which will avoid interfering with traffic flow. In many cases parked cars do the job. Where smooth flow is anticipated, then average speed cameras work to prevent slowing to pass the cameras themselves.
Which potentially increases the death toll. Hardly seems worth increasing the motorway limit to 80mph for example because anyone doing a short journey won't notice the difference, and anyone doing a longer journey like London to Edinburgh already had to allocate a full working day to it. The DfT have consistently ruled this out because there's no demonstrable public benefit. Even if we didn't care about the extra deaths and serious injuries it would result in, the cost of dealing with those will wipe out any economic benefit. Not to mention that anybody who wants to do 80mph already does it because the police forces south of the border routinely offer speed awareness courses for up to 86mph.Ultimately, I still believe we need a package of changes that involve a consistent message and actually allow increases in speed in places where (like 3-lane motorways) it is safe to do so (to the European limit looks reasonable).
Hence there is more of an argument for the UK to go to 130 (80) rather than the other way around. Since clearly 130 is ok in Europe. (Edited to 130, thanks for spotting the error @Bletchleyite )I don't think you would get away politically with dropping to 110 (basically 70 near enough) - that would have to come later if justified.
Carbon emissions remain relevant until every EV is charged wholly from non-carbon-producing generation.
In many cases parked cars do the job.
Hence there is more of an argument for the UK to go to 120 (80) rather than the other way around. Since clearly 120 is ok in Europe.
But it's not clearly ok in Europe? The UK has a lower road death and road casualty rate than almost every other European country except 3 Scandinavian countries (Iceland, Norway, Sweden), which are barely better.Hence there is more of an argument for the UK to go to 120 (80) rather than the other way around. Since clearly 120 is ok in Europe.
Pollution isn't just GhG emissions though. Lower speed limits massively help localised air pollution which comes from particulate matter, e.g. PM2.5/PM10.For emissions the UK is doing better with carbon these days, but I do agree we are not there yet with non-carbon producing generation. I found there is a nice dashboard for people interested in these things.
Dashboard: NESO Dashboard Link
At the latest update the UK is producing 181 grams of CO2 per KWh (which apparently is high) and most of that is from Gas or imported electricity.
Works incredibly well in the valleys here. Though I do see some of the parked cars with cones on their rear corners, or other visibility aids, so presumably some drivers have not been quite so attentive when driving through the resulting chicanes.One of the most effective ways of passively controlling speed in residential areas is by directing where people park to create natural chicanes. I'm surprised we don't do as much of that in this country as we could do to be honest - if you mark clear spaces out and double-yellow the rest (and lay it out so a wrongly parked car would be completely blocking the road, which most drivers won't do, while raising the kerb in that area so they can't park partly on the pavement) you get quite an effective layout for lower speeds which drivers don't overly mind because they recognise that people narrowing the road through parking is just a largely unavoidable aspect of motoring.
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The Euro standard is 130. But I think that will come down, and increasingly is signed down to 110 (about 66).
I can't say for sure that the reason I got asthma when I moved to London and the reason it disappeared when I moved to Scotland is down to air pollution but I'd bet a hefty whack on it.
Speed bumps punish* every driver because a minority drive irresponsibly. My local council has recently installed quite severe humps on a main road (30mph limit) largely because of predominantly younger drivers speeding in evenings to show off. As the road in question is a hill, the speed humps have turned a road that used to be suitable for 4th gear into one that needs 2nd (or 3rd if you're lucky). This increases pollution, reduces fuel economy, and increases wear on vehicle components. There's also an increase in noise for residents, regardless of whether vehicles actually slow down or not. The simple measure that would actually make our roads safer, would be to actively target those drivers who repeatedly drive dangerously, with genuinely punitive penalties.Vertical deflection (e.g. speed bumps, humps, rumble strips, etc) is shown to be (slightly) more effective than cameras in changing driver speed.
I would normally agree that cameras are better than speed bumps for a few reasons, but there's a trend recently of people smashing up speed cameras, burning them, bagging them, etc. It takes a lot more effort to remove speed bumps, they're cheaper to replace, and they don't face quite as much opposition from the, "speed cameras are just a cash cow", crew.
Which is why I'd normally be in favour of cameras.Speed bumps punish* every driver because a minority drive irresponsibly. My local council has recently installed quite severe humps on a main road (30mph limit) largely because of predominantly younger drivers speeding in evenings to show off. As the road in question is a hill, the speed humps have turned a road that used to be suitable for 4th gear into one that needs 2nd (or 3rd if you're lucky). This increases pollution, reduces fuel economy, and increases wear on vehicle components. There's also an increase in noise for residents, regardless of whether vehicles actually slow down or not. The simple measure that would actually make our roads safer, would be to actively target those drivers who repeatedly drive dangerously, with genuinely punitive penalties.
*=Whilst speed limits aren't a punishment, traffic calming measures are- because they impact all drivers including those who were cautious before the measures were imposed.
As noted in my earlier post, pollution is going to be about tyre particulates, which are most heavily impacted by stop-start driving and have a much weaker relationship with speed than tailpipe emissions.But it's not clearly ok in Europe? The UK has a lower road death and road casualty rate than almost every other European country except 3 Scandinavian countries (Iceland, Norway, Sweden), which are barely better.
Pollution isn't just GhG emissions though. Lower speed limits massively help localised air pollution which comes from particulate matter, e.g. PM2.5/PM10.
I can't say for sure that the reason I got asthma when I moved to London and the reason it disappeared when I moved to Scotland is down to air pollution but I'd bet a hefty whack on it.
I simply argue that if we are imposing a set of reductions, there has to be equally scientifically informed consideration of where higher speeds can be implemented. The obvious location being 3-lane motorways (where you can keep a limit of 70 on the left lane if there are concerns about joining). Such motorways are not in urban areas and are more likely to have a clear flow at that speed.
"Cameras are ineffective because sometimes they get vandalised" is the same argument as "Ticket gates are ineffective because sometimes people jump or force them".Which is why I'd normally be in favour of cameras.
Sadly I've lived or worked near too many smashed or burnt down speed (or LEZ/ULEZ/CAZ) cameras to have confidence in their effectiveness, until the government can sort out the criminal damage problem.
It wouldn't. The difference would be a few minutes and accidents would reduce in number and severity.
I would agree with that, where there are significant stretches with houses on the sides of the road then a reduced limit is sensible. My OP Port Talbot example is not such a section, but knowing the M5 and M6 in Birmingham, there are definitely sections that do qualify. Given that there are islands of industrial estates in between I think a blanket limit would be better than constant speeding up and slowing down. Just make sure that the limit starts close to where the houses start and not as far away as my M4 example.Such motorways often do run through urban areas such as the long stretches through Birmingham and the shorter one through Luton. To be honest there'd be a good argument to put a permanent 60 or even 50 on the bit through Brum at least - not only does it go through an area where people live, but also it's congested and has very narrow lanes and deteriorating concrete bridge structures which might last better with a lower limit.
That is going off topic a little, police do need to deal with all crime."Cameras are ineffective because sometimes they get vandalised" is the same argument as "Ticket gates are ineffective because sometimes people jump or force them".
Proper enforcement of laws is what's needed. Perhaps we could do with police spending less time dealing with people who use bad words? But that's another topic altogether.
Speed bumps punish* every driver because a minority drive irresponsibly. My local council has recently installed quite severe humps on a main road (30mph limit) largely because of predominantly younger drivers speeding in evenings to show off. As the road in question is a hill, the speed humps have turned a road that used to be suitable for 4th gear into one that needs 2nd (or 3rd if you're lucky). This increases pollution, reduces fuel economy, and increases wear on vehicle components. There's also an increase in noise for residents, regardless of whether vehicles actually slow down or not. The simple measure that would actually make our roads safer, would be to actively target those drivers who repeatedly drive dangerously, with genuinely punitive penalties.
*=Whilst speed limits aren't a punishment, traffic calming measures are- because they impact all drivers including those who were cautious before the measures were imposed.
Ireland has no lower speed restrictions for new drivers - we have “N” plates here which must be displayed for two years, but no speed restrictions apply.From a safety point of view, very unlikely to raise many limits.
The UK is 10th in the world for road deaths per capita (WHO, 2023). Above us is Iceland, Sweden, Norway, Micronesia. We have a better road safety record than Germany when measured per capita or by number of miles driven. Their road-related death rate per capita is 30% higher than the UK's. For all people point at the Autobahn, the limitless sections have a worse safety record than UK motorways, and large parts of it do actually have speed limits applied. Also anecdotally, German drivers just have better lane discipline in my experience. Middle lane hogging and moving without checking blind spots is rife in the UK.
That's not to say there's no work to be done on road safety. Roughly 1600 people a year die on our roads. Speed is a common factor, with roughly half of speed causes being driving above the limit, and the other half being driving too fast for the conditions but under the limit.
In Scotland our government is debating making single carriageways 50mph for all road users. Currently our limit for wagons is a mere 40mph on single carriageways, which is a huge relative difference from 60mph for cars, car-derived vans, etc. If they follow through with it, it'll be interesting to see the results. The logical step if that's successful would be 60mph for all dual carriageway users. Motorways I think are different in that you can have larger speed differentials, as you usually have 2+ lanes, often 3+, hard shoulders or on 'smart' motorways emergency refuge areas, the lanes are a minimum width to meet motorway standard, etc.
In Wales where my family live, built up areas defaulting to 20mph appears to have been successful, but it'll take a bit longer to get a decent set of data to try and isolate the other factors leading to lower collision, casualty, air pollution rates. TfL's data for this in London is stronger and over a longer period of time, and they do find that the greatest reduction in road kills and seriously injured (KSI) stats come from roads changed to 20mph compared to roads not changed. I could see Scotland going for Wales' 20mph approach or similar, given the recent introduction of pavement parking bans, and trying to bring parity to single carriageway speed limits for different vehicle types.
I also think it's time for Ireland to ditch the 45mph restriction on R-plated drivers. Having people limited to 45mph on motorways where even the wagons are going faster is dangerous. I know it's because the R plate restrictions were in place before they actually had motorways, but times have changed and it's time to update the legislation.
If we are to raise the motorway speed limit to 80mph as some suggest, I think we'd have to revise NPCC's recommendation of 10%+2mph enforcement threshold, and the 10%+9mph recommended limit for speed awareness courses. Otherwise you can be doing nearly 100mph and get away with paying £100 for a course. I'd rather just leave that limit as it is at 70mph. The DfT has ruled out increasing the limit to 80mph for years, so unless we get a Reform UK government, who would certainly do it as a cheap vote winner, I can't see it happening anyway.
How many accidents are there on the A34 and A417/419 compared to other motorways?
Smart motorways don't have hard shoulders so would these be 60mph too?
Over 15 minutes is the difference in time between doing the A34 at 60 compared to 70mph which is pretty significant, for very little justification. It is much larger for the longer sections of A1 which are not upgraded to motorway standards
Ireland has no lower speed restrictions for new drivers - we have “N” plates here which must be displayed for two years, but no speed restrictions apply.
I was referring specifically to Northern Ireland. My friends there refer to it simply as Ireland, but that's a whole other storyIreland has no lower speed restrictions for new drivers - we have “N” plates here.
The Bristol M5-M32 section gets Red X and national speed sometimes, but I believe I have seen it switched off (though from memory the hard shoulder is actually still separated by a solid line and then the smart motorway signs say use hard shoulder (for M32)I don't have stats sorry.
Absolutely. An option might be to red-X Lane 1 at quiet times and put NSL up.
Upgrade them then.
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Differential speeds are what creates risk on higher speed roads, so this is an absolutely insane idea anyway.
The Bristol M5-M32 section gets Red X and national speed sometimes, but I believe I have seen it switched off (though from memory the hard shoulder is actually still separated by a solid line and then the smart motorway signs say use hard shoulder (for M32)
The 6 is enough.Differential speeds are what creates risk on higher speed roads, so this is an absolutely insane idea anyway. Stricter enforcement is all I'd consider, which we already have in getting a ban at 6 points rather than 12. Perhaps this could be reduced further to 3 and speed awareness courses also carry points for new drivers. I'm also strongly of the view that mitigation should never be given based on losing ones's job - if one is a professional driver, one needs to think about that when deciding how to drive at other times too.
Thanks. I tend to be concentrating on driving rather than fully working out what they are doing with the paint. Last week there was 60 40 50 40 60 40 before the national speed limit resumed. The issue was a broken down car in the "hard shoulder" just near the M32 junction meaning the usual 2 lanes going off were having to merge back to 1 and that was then impacting the onward flow of the M4. I rarely use the M32 so am usually somewhere near the middle going past whatever slowness the M32 has created. With that amount of variability in the variable speed, one is often checking speed to avoid holding people up (at increases) and going to fast (at decreases).That's a traditional managed motorway. On those the hard shoulder defaults to closed with NSL, if you open it a 60 limit is applied automatically.
I don't think these are better as they cause confusion (a bit like part-time bus lanes, which I would like to see banned), but we could red-X lane 1 on smart motorways at quiet times.
I don't have stats sorry.
Absolutely. An option might be to red-X Lane 1 at quiet times and put NSL up.
Upgrade them then.
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Differential speeds are what creates risk on higher speed roads, so this is an absolutely insane idea anyway. Stricter enforcement is all I'd consider, which we already have in getting a ban at 6 points rather than 12. Perhaps this could be reduced further to 3 and speed awareness courses also carry points for new drivers (maybe discounted to 2 points rather than 3 if a course is chosen?). I'm also strongly of the view that mitigation should never be given based on losing ones's job or similar - if one is a professional driver, one needs to think about that when deciding how to drive at other times too.
I cannot see how it would be helpful to punish new drivers with essentially losing their licence for one transgression.
I think banning people after 3 points is ridiculous, that's just 1 minor speeding transgression which is easy to do even for experienced drivers