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Speed limiters in cars

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philthetube

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Its the balance between the problems it causes and the problems it solves. 30mph limits solve more problems, and more important problems, than the ones they cause.
Mandatory limiters, depending on how they were implemented, could cause many more problems than they solve.
You maybe right, but if they can save lives and cut crime then they should be investigated.
 
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Chester1

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Personally my vote is for a much higher standard of driving test, with compulsory retakes every 5 years. That would sort out the wheat from the chaff.

I think New Zealand has a two test process. First test grants a severely restricted licence and second test taken after two years grants a full driving licence. I am surprised its not more common. 17 year olds stuck to driving during day time with 1 or 2 passengers can't vote.
Unfortunately the second most dangerous drivers (the elderly) can. Many refuse to accept their limitations. I was banned from being a passenger in my grandparents cars long before any of them gave up their keys. The average 80 somethings spacial awareness and reactions have been shot to pieces. A proper retest at 80 and then at 5 year intervals would make the road safer but would be political suicide.
 

AM9

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I think New Zealand has a two test process. First test grants a severely restricted licence and second test taken after two years grants a full driving licence. I am surprised its not more common. 17 year olds stuck to driving during day time with 1 or 2 passengers can't vote.
Unfortunately the second most dangerous drivers (the elderly) can. Many refuse to accept their limitations. I was banned from being a passenger in my grandparents cars long before any of them gave up their keys. The average 80 somethings spacial awareness and reactions have been shot to pieces. A proper retest at 80 and then at 5 year intervals would make the road safer but would be political suicide.
So what do you mean by your presumption that 'the elderly' are the second most dangerous drivers?
Specifically: what age group is 'elderly'?, is it a raw figure of incidents?, is it adjusted for drivers' exposure to traffic?, does it include injuries and or deaths?, and does it indicate whether drivers were breaking any moving traffic legislation designed to improve safety?
Sweeping unqualified statements add nothing to a meaningful debate.
 

Domh245

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So what do you mean by your presumption that 'the elderly' are the second most dangerous drivers?
Specifically: what age group is 'elderly'?, is it a raw figure of incidents?, is it adjusted for drivers' exposure to traffic?, does it include injuries and or deaths?, and does it indicate whether drivers were breaking any moving traffic legislation designed to improve safety?
Sweeping unqualified statements add nothing to a meaningful debate.

It's not a presumption, it's a fairly well established fact. The road casualty reports bear this out - 2019 example pages 17 onwards are of interest

Chart 9, left hand side is particularly interesting as it shows the normalised casualties (Killed/Seriously Injured/Slightly injured) looking just at the drivers. There's a clear uptick at the 79+ group beyond the "old people are more frail and likely to become a casualty for any given incident" that the RHS of the chart shows. The report goes into a whole load more detail beyond that, though this was an interesting line I thought

There were 287 people killed from accidents involving a young car driver in 2019, a decrease of 7% from the previous year. There were 444 people killed from accidents involving an older car driver in 2019, an increase of 9% from the previous year.


There's also a whole other factsheet about older drivers which generally highlights how they pose a higher risk, though the headline stat about lower casualty rate/distance travelled seems to have been arrived at by including the notoriously risky younger driver group, as Chart 9 in the first linked report shows!
 

LSWR Cavalier

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I was certainly not mature enough to drive a vehicle when I was 17. Retired now, plan to do some more driving, but give up maybe about age 70-75*, already fixed my life so I do not 'need' to drive.

* I worked out when that shall be, and started preparing.
 

miklcct

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See my explanation as to why this change has most likely saved rather than cost lives - it was done for safety reasons, not as a sop to the industry. Overtaking is by far the most dangerous activity on single carriageways, not driving a bit faster. The change has considerably reduced overtaking of lorries by cars on single carriageways, because most car drivers will happily sit at 50 or so on a single but most will not happily sit at 40 so will attempt to overtake, often dangerously.
Frankly it is a bit scary for me that a bus in the UK can drive at 50 mph (80 km/h) even on a single carriageway, as single carriageways are inherently dangerous that I think the most appropriate speed limit should be 40 mph for all vehicles. In contrast, I think some of the motorways can be relaxed to 80 mph (70 mph for heavy vehicles, 50 mph for buses allowing standing passengers).
 

johncrossley

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Frankly it is a bit scary for me that a bus in the UK can drive at 50 mph (80 km/h) even on a single carriageway, as single carriageways are inherently dangerous that I think the most appropriate speed limit should be 40 mph for all vehicles. In contrast, I think some of the motorways can be relaxed to 80 mph (70 mph for heavy vehicles, 50 mph for buses allowing standing passengers).

Single carriageways vary enormously in standard, though. A rural single carriageway built to modern standards, for example a new bypass, would have wide lanes and not have sharp bends. These are very common as the main road in Ireland. In Ireland they may even have a hard shoulder, and would have a 100 km/h speed limit, whereas most lower standard single carriageway roads have a lower speed limit. A single carriageway may have multiple lanes, or be limited access with motorway style slip roads.
 

AM9

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It's not a presumption, it's a fairly well established fact. The road casualty reports bear this out - 2019 example pages 17 onwards are of interest

Chart 9, left hand side is particularly interesting as it shows the normalised casualties (Killed/Seriously Injured/Slightly injured) looking just at the drivers. There's a clear uptick at the 79+ group beyond the "old people are more frail and likely to become a casualty for any given incident" that the RHS of the chart shows. The report goes into a whole load more detail beyond that, though this was an interesting line I thought




There's also a whole other factsheet about older drivers which generally highlights how they pose a higher risk, though the headline stat about lower casualty rate/distance travelled seems to have been arrived at by including the notoriously risky younger driver group, as Chart 9 in the first linked report shows!
The report makes relatively small reference to the age demographic and only in the context of the injuries and deaths resulting from traffic incidents. My comment was on @Chester1's assertion: "Unfortunately the second most dangerous drivers (the elderly) can" which specifically infers that elderly drivers are 'dangerous' (as in the second most 'dangerous' group) and it's unfortuante that they are allowed to drive. There is no evidence that older drivers either cause proportionately more incidents and certainly very little judgements on the prime causes of those incidents going against the older drivers. It is not 'a well established fact' and by conflating the two issues, the 'dangerous driver' point is unfounded and specious almost to the point of malicious.
The report does not make any reference to their driving standards being worse, or even more likely to cause incidents than other groups, it just acknowledges that a higher proportion of them suffer greater health consequences if they are involved in collisions. Most of the incidents that involve elderly drivers involve other motorists and may well have been caused by other drivers outside that age group.
That is why I asked "does it indicate whether drivers were breaking any moving traffic legislation designed to improve safety?" to which there has been no answer.
 

DelW

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Very rare in this country, and I believe grade-separated single carriageways aren't permitted by the design manual. Quite common on the continent though, but obviously Britain knows best... :rolleyes:
They were certainly allowed as late as the mid 1980s, when Alresford bypass in Hampshire was built, 'cos I worked on it ;) . Ilminster on the A303 was another example from around the same time (although IMO that should certainly have been dual, it's a notable source of delays and accidents). They're both fully grade separated, although they do only have junctions at the ends.
 

ABB125

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They were certainly allowed as late as the mid 1980s, when Alresford bypass in Hampshire was built, 'cos I worked on it ;) . Ilminster on the A303 was another example from around the same time (although IMO that should certainly have been dual, it's a notable source of delays and accidents). They're both fully grade separated, although they do only have junctions at the ends.
You are correct in that both those roads are grade separated, but they don't have any actual junctions. I meant something like this at Daventry, apologies if this wasn't clear! :)
 

Nym

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Do the many vehicles that already have speed limiters cause problems with safety that outweigh the benefit? For example HGVs limited at 56 mph and coaches limited at 62 mph. Some London buses have speed limiters that can adjust automatically to 20 mph and 30 mph zones. Are these dangerous?
Yes.
How many of these vehicles with limiters are deliberately defeated by operators in such a way that does things like, disable the function of the ABS so that they can get to their drop quicker?
How many drivers that use irresponsible speed, would apply similar "fixes" and then have similar causal issues, rendering the roads less safe because the safety systems of that vehicle are also disabled.
How many drivers of vehicles will choose not to buy new vehicles with lower emissions because of these limiters, causing an uplift in emissions on the roads and actually resulting in more deaths due to poor air quality?
 

Chester1

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The report makes relatively small reference to the age demographic and only in the context of the injuries and deaths resulting from traffic incidents. My comment was on @Chester1's assertion: "Unfortunately the second most dangerous drivers (the elderly) can" which specifically infers that elderly drivers are 'dangerous' (as in the second most 'dangerous' group) and it's unfortuante that they are allowed to drive. There is no evidence that older drivers either cause proportionately more incidents and certainly very little judgements on the prime causes of those incidents going against the older drivers. It is not 'a well established fact' and by conflating the two issues, the 'dangerous driver' point is unfounded and specious almost to the point of malicious.
The report does not make any reference to their driving standards being worse, or even more likely to cause incidents than other groups, it just acknowledges that a higher proportion of them suffer greater health consequences if they are involved in collisions. Most of the incidents that involve elderly drivers involve other motorists and may well have been caused by other drivers outside that age group.
That is why I asked "does it indicate whether drivers were breaking any moving traffic legislation designed to improve safety?" to which there has been no answer.

I never indicated elderly drivers were dangerous for rule breaking! Any increase risk with age will be due to increasing reaction times etc. I was suggesting young drivers and the elderly (id define that as 80+ or maybe 85+) would be a good place to start if @Bald Rick got his way and 5 yearly testing was introduced. Perhaps I am scarred by memories of young reckless friends and grand parents who thought they were fine driving until their late 80s (two regularly drove on motorways at 85+). Call me ageist but an 87 old behind wheel of a car doing 70 (and higher) is rarely a good idea! In an ideal world I would tackle young and old driving quality first then everyone else. Its politically viable to introduce a New Zealand style system for new drivers but unfortunately re-testing any existing drivers will never happen because many people think driving is a God given entitlement regardless of changing circumstances.

Breaches of lower speed limits can't be stopped easily but limiters can stop speeding on motorways and that is better than nothing. I hope insurers price younger drivers out of driving a car without a limiter. Allowing 17 year olds to legally drive vehicles capable of doing twice the national speed limit beggers belief.
 

zero

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5 year testing would require 10 times the number of examiners assuming 50 years of driving in a lifetime, unless the revalidation tests were a lot shorter.

This may lead to a lower standard of examiner unless you think there are thousands of good drivers wanting to become examiners but can't because there aren't any vacancies...

As a 30 year old I would love to have a self driving car but I don't see how it can work with the quality of some roads in the UK, especially all those terrace rows where just getting to the next junction is a complex negotiation.
 

edwin_m

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I dislike Elon and his fanboys just as much as you do, don't worry. I very much hope whatever the future holds, he plays no role!

At-grade crossings can be solved with enough willpower (you could have some sort of stop signal that the car can read, which is activated by a pedestrian pushing a button to indicate they want to cross the road, for example. Maybe you could have different sorts of interfaces and name them after birds!)

Solve the ethics/responsibility issues (or perhaps even better, separate the 2 ton death boxes and the squishy pedestrians/cyclists) and all the other technological hurdles and there's no reason not to have driverless cars. I'm under no illusion that it's several decades away yet
It would cost a huge amount to disfigure the environment with these things every 100 yards, and they would still need the lights on sticks because there will still be human drivers, as well as the audible signal which must be infuriating to local residents (though other countries do this much better). And how would it work on rural roads with no footways?

It would also send completely the wrong message on urban priorities. We shouldn't be imitating the American jaywalking laws, introduced after lobbying efforts by the motor industry which created the mindset that the vulnerable pedestrian was to blame for the accident by deigning to trespass on the territory of the two-ton vehicles. There should be a presumption that people can cross the road anywhere it's safe to do so, and drivers should always be expecting this except on segregated fast roads.
 

Meerkat

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5 year testing would require 10 times the number of examiners assuming 50 years of driving in a lifetime, unless the revalidation tests were a lot shorter.
For the older driver issue would they really need an examiner retest?
I was thinking of a fairly simple simulator set up that can check eyesight and reaction times.
Simplest wouldnt even need a steering wheel, but more involved ones might throw a situation in that needs quick judgment and steering round something (might have an additional health benefit of throwing out those that might be developing dementia type issues that can be helped)
With the really old drivers the physical reaction times scare me a bit - I see how difficult it is for them to get in the car and wonder how quick they can move from accelerator to brake and how hard they can stand on that brake….and when you see how long it takes some to turn their head when turning out of a T junction!!
Re-testing would have limited use for the kids. From my own experience I was plenty able to drive ‘properly’ when it mattered - ie when driving parents about!

ps as a response to old folk saying ‘it’s not fair’ - the kids these days have to do a much harder test now than even I had to do, let alone the old old people.
 

AM9

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For the older driver issue would they really need an examiner retest?
I was thinking of a fairly simple simulator set up that can check eyesight and reaction times.
Simplest wouldnt even need a steering wheel, but more involved ones might throw a situation in that needs quick judgment and steering round something (might have an additional health benefit of throwing out those that might be developing dementia type issues that can be helped)
With the really old drivers the physical reaction times scare me a bit - I see how difficult it is for them to get in the car and wonder how quick they can move from accelerator to brake and how hard they can stand on that brake….and when you see how long it takes some to turn their head when turning out of a T junction!!
Re-testing would have limited use for the kids. From my own experience I was plenty able to drive ‘properly’ when it mattered - ie when driving parents about!

ps as a response to old folk saying ‘it’s not fair’ - the kids these days have to do a much harder test now than even I had to do, let alone the old old people.
I agree that any testing designed to asess whether drivers are still able to drive a vehicle safey should in the case of elderly drivers, establish that their essential faculties are still compatible with safe control of a vehicle. There's no point in subjecting every driver over a certain age as to whether they know the rules of the road. There is however a case for subjecting every driver to a theoretical test of road laws and rules that they need to be familiar with to drive safely. Those rules (and the roads that they apply to) change as the years go by, so a regular theoretical refresh test (say every 5-10 years) should be applied irrespective of age.

I never indicated elderly drivers were dangerous for rule breaking! Any increase risk with age will be due to increasing reaction times etc. I was suggesting young drivers and the elderly (id define that as 80+ or maybe 85+) would be a good place to start if @Bald Rick got his way and 5 yearly testing was introduced. Perhaps I am scarred by memories of young reckless friends and grand parents who thought they were fine driving until their late 80s (two regularly drove on motorways at 85+). Call me ageist but an 87 old behind wheel of a car doing 70 (and higher) is rarely a good idea! In an ideal world I would tackle young and old driving quality first then everyone else. Its politically viable to introduce a New Zealand style system for new drivers but unfortunately re-testing any existing drivers will never happen because many people think driving is a God given entitlement regardless of changing circumstances.

Breaches of lower speed limits can't be stopped easily but limiters can stop speeding on motorways and that is better than nothing. I hope insurers price younger drivers out of driving a car without a limiter. Allowing 17 year olds to legally drive vehicles capable of doing twice the national speed limit beggers belief.
Maybe your words didn't make that clear, but the reports on road incidents do have plenat to show that older drivers are more likely to sustain injury or worse than a younger fitter person in exactly the same situation for the reason that their bodies are less robust and their recoveries from injuries take longer.
The 2019 road casuality report by linked by @Dom245 in post #95 uses assessment methods introduced in a study by the Journal of Safety Research in 2018, (see here) which exhaustively looks at the relationships between risk of accidents involving death adjusted for exposure to the risk.

The concluding statemant in that document says:
The current study applied a new approach to model crash risks based on exposure metric that bears a linear relation with crashes. Our findings draw attention to the invalidity of crash rates for risk comparisons among groups and conditions that vary in driving exposure. Specifically, we have demonstrated that conventional crash rates overestimate the actual risk of crash involvement and fatal injury for the youngest and oldest drivers as well as for nighttime driving. This work has important practical implications for improving road safety initiatives, as meaningful comparisons are essential for identifying truly at-risk drivers and driving conditions.
Any road incidents with injuries or death occuring is a cause for concern but there is no evidence that (adult) age alone determines this risk and implying such a risk is misleading, - for instance if a car with a 30 year old driver is in a serious collision, there is more likely to be a death or serious life changing injury if the passenger in the front seat is say 80 years old rather than just 30 years old. Neither accident would be attributed to the passenger, but the blind assumption that more old people are killed meaning that they consequently need more testing or even banning after a certain age to fix that would be misleading to say the least.
 
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caplimilan

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It's the right thing to do. It helps to avoid any accidents. Although among my acquaintances there are people who consider this option in cars useless. I, on the contrary, believe that this way, you keep yourself and others safe. Yes, of course, there are situations in which it is necessary to press the speed limit and rush, but it's also a risk, isn't it? I took out Money Expert car insurance if I have to drive with all my might and put myself in danger one day. Besides, even at low speeds, there is always the possibility of getting into an accident
 
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The exile

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The sooner humans are no longer in control of vehicles, the better!
The problem is that there are a lot of circumstances which require the “ last mile human” - which means a need to allow for manual control / override - at least until perfect voice- control can be guaranteed!
 

JamesT

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If vehicles had a perfect knowledge of their environment and what the correct speed is it might be plausible, but as it stands, no.
My current car has a forward-facing camera to pick up speed limits and display them on the dashboard (and then warn when current speed is above the limit). Naturally you’d say that could be turned into the automated limiter system proposed. But the number of times it gets that wrong, such as not realising the end of restrictions on the matrix sign applies or picking up the 5mph limit on the building site next to the road I’m on, don’t give confidence.
 

apk55

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One of the problems with automated systems is coping with the unexpected. For example on more than 1 occasion over the I have had to preform normally illegal moves (under the command of traffic police) such as doing a U turn on a motorway and driving the wrong way back to an exit as there has been a serious crash and the motorway was blocked. Therefore the system has to allow for this type of situation and needs to be over ridden.
 

87 027

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Agreed. The premise of this thread was removing control from the driver to prevent deliberately reckless acts. So there needs to be a way of dealing with situations such as in the post above that might be practically necessary but the automated system can't cope with because it isn't in the ruleset or machine learning data it has been trained on. A low probability of them happening doesn't equate to zero.

A few years ago whilst driving in my own car on holiday in France I encountered a complete block on the main A1 autoroute due to a crash, so under the direction of the police had to exit by one of the periodic gates that exist as escape routes and drive across a farmer's field to get to the nearest D road to continue the diversion.
 

SeanG

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One must remember with speed limiters that some cars are allegedly limited already, although are not actually limited.
For example mine is limited to 155mph but will easily crack 165+
 

Factotum

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Frankly it is a bit scary for me that a bus in the UK can drive at 50 mph (80 km/h) even on a single carriageway, as single carriageways are inherently dangerous that I think the most appropriate speed limit should be 40 mph for all vehicles. In contrast, I think some of the motorways can be relaxed to 80 mph (70 mph for heavy vehicles, 50 mph for buses allowing standing passengers).
Single carriageway roads have bad accident rates because overtaking is a dangerous maneuver on them.
Limiting the speed of buses would encourage more overtaking and more accidents
 

miklcct

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Single carriageway roads have bad accident rates because overtaking is a dangerous maneuver on them.
Limiting the speed of buses would encourage more overtaking and more accidents
So all vehicles should be limited at 40 mph on single carriageways.

I believe, in general, urban should be 30, rural single carriageway should be 40, dual carriageway should be 50 but can be signposted to 60 for higher standard roads, motorway should be relaxed to 80 of the design is safe to do so.
 

Factotum

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For the older driver issue would they really need an examiner retest?
I was thinking of a fairly simple simulator set up that can check eyesight and reaction times.
The lower reaction time of older people is generally compensated by their much better anticipation gained by years of experience.
A young lad with a reaction time of 100mS who doesn't start to react until he is on top of an incident is more dangerous than and old man with a 250mS reaction time who sees the danger when he is 25 metres from it.
 

Meerkat

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The lower reaction time of older people is generally compensated by their much better anticipation gained by years of experience.
A young lad with a reaction time of 100mS who doesn't start to react until he is on top of an incident is more dangerous than and old man with a 250mS reaction time who sees the danger when he is 25 metres from it.
That only works comparing the old against novice drivers, who are already heavily controlled and penalised. The old folk will have worse anticipation than the huge middle group due to doing fewer miles (at cripplingly low speed :lol: )
 
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