UKC

Leeds Uni research shows fewer accidents for Smart Motorways

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 Offwidth 09 Jun 2021

As reported on More or Less this am. Researchers compared before and after sections of motorway were made Smart and found accident rates reduced after. The item starts just after 8 minutes in.

https://www.bbc.co.uk/programmes/m000wsf0

 neilh 09 Jun 2021
In reply to Offwidth:

That was why they were brought in in the first place. 
 

Does not surprise me at all. Apparently they was lots of stat analysis done to show the difference.

 mondite 09 Jun 2021
In reply to neilh:

> That was why they were brought in in the first place. 

The problem though is "smart motorway" covers a lot of different things. Even at the basic level the newer ones were built with different and lower standards than the original ones.

 Offwidth 09 Jun 2021
In reply to mondite:

They looked at that. They said they were all safer.

 neilh 09 Jun 2021
In reply to Offwidth:

Exactly.

In reply to Offwidth:

An overall improvement in safety due to speed management (which would apply to any motorway) sure but does that change the fact that breaking down with no hard shoulder and being unable to make it to a refuge is a death sentence?

In reply to DubyaJamesDubya:

> An overall improvement in safety due to speed management (which would apply to any motorway) sure but does that change the fact that breaking down with no hard shoulder and being unable to make it to a refuge is a death sentence?

It doesn't change the result. The roads are safer comparing the exact same road before and after, listen to it, they measured deaths per mile/per user etc.  It was a proper study, not some government ministers trying to justify policy. 

 Duncan Bourne 10 Jun 2021
In reply to summo:

> It doesn't change the result. The roads are safer comparing the exact same road before and after, listen to it, they measured deaths per mile/per user etc.  It was a proper study, not some government ministers trying to justify policy. 

That might be the case but does it mean the motorway is as safe as it should be.  I drive an older vehicle and  I wonder if I'm taking my life in my hands every time I go onto one of these 'cheaper' smart motorways

In reply to DubyaJamesDubya:

> That might be the case but does it mean the motorway is as safe as it should be.  I drive an older vehicle and  I wonder if I'm taking my life in my hands every time I go onto one of these 'cheaper' smart motorways

You're at less risk on the same road now, than you were before. Listen to the article.

If you follow the rules when you breakdown you aren't at risk, hazards immediately as soon as you can't maintain road speed, exit vehicle etc... Even when there is a hard shoulder many people don't know that they shouldn't stay with the vehicle. 

 Brown 10 Jun 2021
In reply to DubyaJamesDubya:

Hang on here. This is UKC. If you have any doubts about the safety of your equipment you should throw it away and buy new.

After all, you must value your life more that the value of your car etc etc

 ianstevens 10 Jun 2021
In reply to Brown:

I mean you’re being facetious I expect but... if you are genuinely worried your vehicle might break down, then perhaps it is a good idea to do something about it?

 JHiley 10 Jun 2021
In reply to Offwidth:

That's great but it seems like a sort of misdirection. The issue people are concerned about is the hard shoulder being removed. Lumping all the other "smart" stuff in with this just confounds the issue.

 mondite 10 Jun 2021
In reply to summo:

> You're at less risk on the same road now, than you were before. Listen to the article.

Actually not in all cases if you read the report. ALR and DHS has higher serious casualties and its also worth noting given the years they are looking at the ALR in particular will have been built to a higher standards than those being converted at the time (especially in terms of distance between stops).

Plus they shouldnt be comparing ALR/DHS against unconverted motorways but instead just against CM and whether there would be ways to improve those (eg retain hard shoulders but also add refuge areas).

In reply to mondite:

The speed control is clearly hugely beneficial, and I agree on refuge areas.  So indeed why not go for the best (safety wise) of both worlds?  That is, add speed control and refuges and keep the hard shoulder.

 Offwidth 10 Jun 2021
In reply to DubyaJamesDubya:

I agree completely that more regular refuges would reduce accidents further: I'd certainly favour that.  My caution on your perception argument is cars occasionally got stranded in live lanes in the old system (the Smart Motorway can cut risk for such a stranded car and close lanes) and breaking down on the hard shoulder in the old system was a lot more dangerous than some perceived it to be.

 Cobra_Head 10 Jun 2021
In reply to mondite:

> The problem though is "smart motorway" covers a lot of different things. Even at the basic level the newer ones were built with different and lower standards than the original ones.


Lower standards of what?

 Cobra_Head 10 Jun 2021
In reply to DubyaJamesDubya:

> That might be the case but does it mean the motorway is as safe as it should be.  I drive an older vehicle and  I wonder if I'm taking my life in my hands every time I go onto one of these 'cheaper' smart motorways


You could make it really really safe and stop people driving on it altogether.

Why are you taking your life in your hands, it's SAFER than the original, you should be more worried about the old type, how don't you get this?

People still got killed on the hard shoulder.

Post edited at 10:07
 Offwidth 10 Jun 2021
In reply to Neil Williams:

Either the expense of that would be huge (all the bridges would need replacing and large amounts of extra land needed), or in the current space you would lose a live lane. 

In reply to Offwidth:

> Either the expense of that would be huge (all the bridges would need replacing and large amounts of extra land needed), or in the current space you would lose a live lane. 

ITYM "we would be doing it properly and not trying to gain an extra lane on the cheap at the expense of peoples' lives".

That said, one thing that might be worth looking at is making the default that lane 1 is closed (red X except approaching and just after junctions, when it could provide an extra acceleration lane for a gantry or two), and only opening it when it is needed.  And when it is needed, dropping the limit to 60 or even 50.  This is how the ones with actual hard shoulder running worked - if you opened the shoulder the limit automatically dropped to 60.

Actual hard shoulder running did cause confusion as some were reluctant to use it, but this would be different.

It could perhaps be made distinct by using long (hazard) road markings alongside it rather than the normal short ones.

Post edited at 10:25
 mondite 10 Jun 2021
In reply to Cobra_Head:

> Lower standards of what?


Primary difference is the refuge areas. For the trial it was a quarter of a mile apart but for newer ones up to two and a half miles. This is being changed down to one mile but is still a rather long way to go.

 mondite 10 Jun 2021
In reply to Offwidth:

> My caution on your perception argument is cars occasionally got stranded in live lanes in the old system (the Smart Motorway can cut risk for such a stranded car and close lanes) and breaking down on the hard shoulder in the old system was a lot more dangerous than some perceived it to be.

Thats an argument for the CM approach with the possible additions of refuge areas on top of the hard shoulder.

Which aside from people who like to speed and so dont like all the cameras on smart motorways and those (probably a substantial overlap) who thinks its a ploy to start lowering the speeds on motorways I dont think anyone objects to.

Which is the entire problem of just using smart motorways as a blanket statement.

In reply to mondite:

I don't see it as a refuge problem. I see it being a car and driver problem. Speed limit all cars 80mph max, power limit too, make the driving test harder, or 10 yearly retest, perhaps add in a motorway test. Maybe motorway limits automatically drop to 50 or 60mph in any poor weather. 

It's not hard to make roads safer, it just won't be popular. 

 Offwidth 10 Jun 2021
In reply to Neil Williams:

It's only been done on the cheap in respect of foolish tweeks (widened gaps between refuges), so on that specific point I'd agree with the quote. On the big picture, the system has massive improvements in throughput for less risk and as such it has been a success, even if it could be safer at relatively low additional costs.

Providing an extra lane on our busiest motorways would cost many tens of billions and would be a decades long project. By that time various factors such as tolls, driverless cars, better public transport, might have improved throughput and reduced risk to the point we won't need such widening. Like the HS2 white elephant I think we would risk solving todays problems for a future that needs different solutions (none of the arguments for HS2 stack up now that costs and land use exceed that of two standard lines which would increase rail capacity more).

In reply to Offwidth:

To be fair, with improved automatic stationary vehicle detection it could well be safer.  I was quite shocked by how bad this actually is given that there is 100% CCTV coverage.  As soon as the vehicle comes to a stop with others not having done so, it should whack 40 across all lanes and close the inner two.  Even with a shoulder closing the inner lane would be sensible.

Another cheaping out that could do with being fixed is that every entrance slip should have a limit sign at the top.  A few do (e.g. the Luton Airport on-ramp) but most don't, which means you're guessing which speed to accelerate to.

Post edited at 11:00
In reply to ianstevens:

> I mean you’re being facetious I expect but... if you are genuinely worried your vehicle might break down, then perhaps it is a good idea to do something about it?

There are a lot of older vehicles on the road and breakdown cover is a thing. 

 Offwidth 10 Jun 2021
In reply to mondite:

The research showed what it did. Wider work on the best ways to run our motorways is always welcome. What I don't want to see is massive investments in wider roads at a time when we should be looking at our transport infrastructure more holistically in a much greener way. It's the same reason why I talk about HS2 a lot and still it goes on, despite no evidence that counters the fundamental economic points on cost, land use and improved capacity that I made above. HS2 has other nasty implications including more especially valuable countryside is lost as the path needs to be straighter, let alone black swan things like the additional vulnerability to terror attacks.

 ianstevens 10 Jun 2021
In reply to DubyaJamesDubya:

I’m aware, having owned both. However you can have a well maintained older vehicle that you can be confident won’t break down barring rare events, and that’s what your breakdown cover is for. If you are concerned that your vehicle will break down every time you drive on a road, then you should do something about it - preventative maintainable is key. 

I’m not saying rare events don’t happen; far from it, just that I suspect a lot of breakdowns are linked with “that strange sound/smell/feeling” when driving.

 gravy 10 Jun 2021
In reply to Offwidth:

How does the rate change with risk profile? I can believe fewer accidents of a minor variety but more of a very serious variety.

 Cobra_Head 10 Jun 2021
In reply to mondite:

> Primary difference is the refuge areas. For the trial it was a quarter of a mile apart but for newer ones up to two and a half miles. This is being changed down to one mile but is still a rather long way to go.


That might be true, but even where there is continuous hard shoulder, people get killed on them. To be honest if drivers were more aware, you don't need refugee areas at all, the signs tell you of a lane closure, it's drivers ignoring these which make it dangerous.

On normal motorway with a hard shoulder, no one gets a warning of a broken down car.

 Cobra_Head 10 Jun 2021
In reply to Neil Williams:

> Another cheaping out that could do with being fixed is that every entrance slip should have a limit sign at the top.  A few do (e.g. the Luton Airport on-ramp) but most don't, which means you're guessing which speed to accelerate to.

Can't you work that out from the speed of the other vehicles?

In reply to ianstevens:

> I’m aware, having owned both. However you can have a well maintained older vehicle that you can be confident won’t break down barring rare events, and that’s what your breakdown cover is for. If you are concerned that your vehicle will break down every time you drive on a road, then you should do something about it - preventative maintainable is key. 

> I’m not saying rare events don’t happen; far from it, just that I suspect a lot of breakdowns are linked with “that strange sound/smell/feeling” when driving.

My car has never broken down. My normal route home from work should involve 5 miles of 'smart' motorway everyday. It's nice to know that it is safer for the average user, it's not nice to be thinking that a breakdown/puncture is very risky if you can't get to a refuge. Given what is at stake a 'rare occurrence' is something I'd rather not risk.

In reply to Cobra_Head:

> That might be true, but even where there is continuous hard shoulder, people get killed on them. To be honest if drivers were more aware, you don't need refugee areas at all, the signs tell you of a lane closure, it's drivers ignoring these which make it dangerous.

It's not as simple as that. Motorways do have bends and the gantries are not every 50m, it's entirely possible to be past a gantry when (and if, in the current badly monitored system) the lane is closed, go around a bend and and be forced to go from 70 to 0 pronto, together with all traffic behind you, as the lane to the right might very well be busy. 

> On normal motorway with a hard shoulder, no one gets a warning of a broken down car.

Sure, but people don't drive on the hard shoulder as a matter of course, accidents do happen on the hard shoulder but fundamentally it is a lane without traffic. Speed awareness courses and the like love to cite some entirely bullshit statistics of the expected lifetime of a vehicle on the hard shoulder, which some moron has calculated as the average time it took for a vehicle to be hit out of all vehicles that *were* hit.

 mondite 10 Jun 2021
In reply to Cobra_Head:

> That might be true, but even where there is continuous hard shoulder, people get killed on them. To be honest if drivers were more aware, you don't need refugee areas at all,

Eh? The primary rational for a refugee area is surely that if someone is in it then you dont need to close the lane off (until its time to get them out again).

> the signs tell you of a lane closure, it's drivers ignoring these which make it dangerous.

true. Travelling on the m25 they do seem to be treated mostly as pretty pictures.

> On normal motorway with a hard shoulder, no one gets a warning of a broken down car.

Which is an argument for CM not ALR/DHS motorways.

In reply to Cobra_Head:

> Can't you work that out from the speed of the other vehicles?

Yes, but it's better not to enter a speed-limited area without knowing the limit first!

In reply to Alkis:

> It's not as simple as that. Motorways do have bends and the gantries are not every 50m, it's entirely possible to be past a gantry when (and if, in the current badly monitored system) the lane is closed, go around a bend and and be forced to go from 70 to 0 pronto, together with all traffic behind you, as the lane to the right might very well be busy. 

That of course is always a possibility as there could be standing traffic or an accident round the bend.

Perhaps we should be prosecuting people who "rear end" a stationary vehicle as a matter of course?

Post edited at 14:48
In reply to Neil Williams:

> That of course is always a possibility as there could be standing traffic or an accident round the bend.

True.

> Perhaps we should be prosecuting people who "rear end" a stationary vehicle as a matter of course?

I'd be up for that, seeing as the only accident I've ever been in was someone crashing into the back of me as I stopped at a red light.

 neilh 10 Jun 2021
In reply to Alkis:

I am struggling to think of any Motorway which has a serious bend where that would be an issue ...can you think of any?

You might get one on a slip road.

 SAF 10 Jun 2021
In reply to Offwidth:

I'd like to see a breakdown of the data to see if it is less accidents overall on smart motorways including less serious accidents/ fatalities or if they are fewer accidents but the ones that do happen have worse outcomes.

The area I work has duel carriageway with no hard shoulder rather than motorways and there are frequently horrific accidents involving cars hitting stationary broken down hgv's and hgv's driving over broken down cars.  Sadly during my career this has included 2 child fatalities in these circumstances.

 RobAJones 10 Jun 2021
In reply to SAF:

I think this is the research that more or less were referring to

https://committees.parliament.uk/writtenevidence/25539/html/

The high-level statistics research presented highlights that the average number of casualties of all severities and for all types of smart motorway have decreased after implementation compared to before. 

 fred99 11 Jun 2021
In reply to Alkis:

> True.

> I'd be up for that, seeing as the only accident I've ever been in was someone crashing into the back of me as I stopped at a red light.

I got rear-ended (on my motorbike !) last Friday as I was stationary waiting to go onto a roundabout. Anything that makes people think before they shunt is good by me !

(At least there was a full admission of guilt by the other party)

Now waiting at home for the assessor to turn up.

In reply to fred99:

Oh dear! :-/

 Kalna_kaza 11 Jun 2021
In reply to mondite:

When you need to stop on a motorway a mile is a VERY long distance. 2.5 miles is criminal negligence in terms of safety.

All lane running removes that immediate safety buffer when all you have time to do is hit the hazard warning light and guide the car to a controlled stop before losing forward momentum. 

Yes speed is a massive factor, but a vehicle hitting you at 50 rather than 70 doesn't buy you the same escape time as a hard shoulder.

 Cobra_Head 11 Jun 2021
In reply to mondite:

> Eh? The primary rational for a refugee area is surely that if someone is in it then you dont need to close the lane off (until its time to get them out again).

Not true, it's a safer place to be that's all, once a vehicle is in the refuge area the lane is still closed off.

> Which is an argument for CM not ALR/DHS motorways.

It's an argument which demonstrates older motorways aren't as safe as some people are making out, that's all. You could put sensors and cameras everywhere, but at what cost?

It also is dependant on other drivers to act on the warning signs, the problem isn't one of not being notified, it's about people ignoring the signs.

 Cobra_Head 11 Jun 2021
In reply to Alkis:

> It's not as simple as that. Motorways do have bends and the gantries are not every 50m, it's entirely possible to be past a gantry when (and if, in the current badly monitored system) the lane is closed, go around a bend and and be forced to go from 70 to 0 pronto, together with all traffic behind you, as the lane to the right might very well be busy. 

You're making stuff up now, give us an example of a motorway with a bend with less than 315 feet clear view.

 Cobra_Head 11 Jun 2021
In reply to Neil Williams:

> Yes, but it's better not to enter a speed-limited area without knowing the limit first!


But all speed controlled areas, do have signs on the slip-roads joining them! Also, there is a set of signs before the cameras, so even if you ignore the general mass of cars you're joining, you can see what speed you should be doing and can then act accordingly.

It's a bit of a weak argument, to be honest.

 mondite 11 Jun 2021
In reply to Cobra_Head:

> Not true, it's a safer place to be that's all, once a vehicle is in the refuge area the lane is still closed off.

Someone needs to tell the people managing the M25 in hertfordshire that since its normal for vehicles to be in the refuge areas without the lanes being closed.

I remember (whilst sitting in a queue so I could read it) a refugee area having a sign next to a phone saying something like "please call before trying to exit so we can ensure its safe".

> It's an argument which demonstrates older motorways aren't as safe as some people are making out, that's all.

No one is claiming that.

In reply to Cobra_Head:

> But all speed controlled areas, do have signs on the slip-roads joining them!

There is a sign stating there is a variable speed limit, but not what the limit is.

> Also, there is a set of signs before the cameras, so even if you ignore the general mass of cars you're joining, you can see what speed you should be doing and can then act accordingly.

And potentially need to panic-brake.

> It's a bit of a weak argument, to be honest.

Where else in the UK is there a speed limit you can enter without knowing what it is, and thus potentially be subject to enforcement action?  If it was orange flashers (not legally binding) I wouldn't care, but if I am subject to a law which could lose me my licence I want to know what it is before I enter that area.

Not providing it is just doing things on the cheap.

Post edited at 11:02
 Cobra_Head 11 Jun 2021
In reply to Neil Williams:

> Where else in the UK is there a speed limit you can enter without knowing what it is, and thus potentially be subject to enforcement action?

But you are warned a long time before you pass the cameras what the speed is, the cameras are on the backside of the gantry displaying the speed limit, they are clearly visible from a long distance, so unless there's something wrong with your eyes, or you are really exceeding to speed limit anyway, there should be plenty of time to slow down without panic braking or getting a ticket.

 Cobra_Head 11 Jun 2021
In reply to mondite:

> I remember (whilst sitting in a queue so I could read it) a refugee area having a sign next to a phone saying something like "please call before trying to exit so we can ensure its safe".

There a valid safety reason for this :-

"Unlike a traditional hard shoulder, which provides enough space to build up speed before re joining the flow of traffic, the emergency refuges on a Smart Motorway do not have enough space for this. Therefore, Highways England will either send a Traffic Officer to help you or set the motorway signs to temporarily close lane one so you can safely re join the motorway"

In reply to Cobra_Head:

> But you are warned a long time before you pass the cameras what the speed is, the cameras are on the backside of the gantry displaying the speed limit, they are clearly visible from a long distance, so unless there's something wrong with your eyes, or you are really exceeding to speed limit anyway, there should be plenty of time to slow down without panic braking or getting a ticket.

That assumes there isn't enforcement in addition to the fixed cameras.

Fundamentally it should not be possible to join a road from another road without knowing what the limit is.

 Offwidth 11 Jun 2021
In reply to Neil Williams:

I agree. I'd add that at most junctions it's obvious on Smart sections so it doesn't require so much expense to prioritise where it's not. It's like making an expensive cake and scrimping on the decoration.

Something else that annoys me is I studied the massive benefits of traffic light entry onto near saturated motorways back in University in the early 80s and still  too few junctions on busy sections have this.

Post edited at 12:18
 mondite 11 Jun 2021
In reply to Cobra_Head:

> There a valid safety reason for this :-

Yes, I know. I was referencing it since it contradicted your claim about the lane being closed if someone is in the refugee area. They arent as standard but may be closed to allow someone to rejoin. In my experience though they seem to prefer having a highways vehicle or two do a rolling block probably because there enough tw*ts who think the red cross means drive fast and undertake.

 Cobra_Head 11 Jun 2021
In reply to Neil Williams:

> That assumes there isn't enforcement in addition to the fixed cameras.

Where do they do this? If you're suggesting road works then I've not joined without there being signs. Otherwise I've never seen this scenario, why have extra enforcment cameras when they already got them?

> Fundamentally it should not be possible to join a road from another road without knowing what the limit is.

Agreed, but I'm not convince these exist, at least to any great extent.

 Jon Greengrass 11 Jun 2021
In reply to Duncan Bourne:

In conclusion. Ask the right question get the "right" answer. 

In reply to Cobra_Head:

Erm, the A1(M) in various places, although that is not a Smart Motorway yet. See how much of a view ahead you'd have here if you were driving at the speed limit on what is currently the hard shoulder:

https://goo.gl/maps/pTY4vA2bauJhqXEW7

Edit: Also, the M1 in a section that is ALR:

https://goo.gl/maps/TVDJuDekeS3Y4HcGA

Note that you will have to spot that the vehicle coming into view is actually stopped, in time to switch lane and/or stop as necessary, and you might be in a loaded vehicle that has a significant stopping distance. Plus add the unfortunate fact that people don't have perfect form in noticing things.

Edit 2: M1 again but not ALR yet: https://goo.gl/maps/RTVQMxNXe8uiw2nH6

Post edited at 14:34
 Cobra_Head 11 Jun 2021
In reply to Alkis:

> Erm, the A1(M) in various places, although that is not a Smart Motorway yet. See how much of a view ahead you'd have here if you were driving at the speed limit on what is currently the hard shoulder:

What distance do you think that is? And as you say it's not a Smart Motorway yet, so what's the point of posting it?

> Edit: Also, the M1 in a section that is ALR:

> Note that you will have to spot that the vehicle coming into view is actually stopped, in time to switch lane and/or stop as necessary, and you might be in a loaded vehicle that has a significant stopping distance. Plus add the unfortunate fact that people don't have perfect form in noticing things.

> Edit 2: M1 again but not ALR yet: https://goo.gl/maps/RTVQMxNXe8uiw2nH6

But all of this doesn't change the facts from the research, that Smart motorways are safer. Giving examples of areas which might be dangerous in the future, without ANY idea of what might be put in place to mitigate the issue, by the time it becomes a Smart motorway is pointless.

 Glug 11 Jun 2021
In reply to Alkis:

If you can't stop your car in that distance, maybe you should have the brakes checked or pay more attention to the road.

 robhorton 11 Jun 2021
In reply to Neil Williams:

> There is a sign stating there is a variable speed limit, but not what the limit is.

I can't think of anywhere where this is the case although I've not checked every junction. If you did get a ticket without passing a speed limit sign though I think you'd have a pretty good case that the limit didn't apply to you (assuming you weren't breaking the national limit!).

In reply to Glug:

I can stop it just fine. Can the loaded lorry behind me stop his?

In reply to Cobra_Head:

The second one is ALR. There are plenty of places on motorways that look just like that. My point is, they should stick to the original refuge area spacing. I am not against smart motorways, I am against them cutting corners on a particular type of smart motorway, which they currently are doing.

The idea that a hard shoulder is as dangerous as breaking down on a live lane that may well take several minutes to shut down at the moment (as they do not have automatic monitoring and do not manually monitor the lanes constantly either, by their own admission in a recent inquest about a deadly accident on an ALR) is frankly absurd. It's also *not* what the statistics show.

From the report:

Casualty rates on all motorway types are lower than A Roads on the SRN, for each type of severity and the Fatal and Weighted Injuries measure.
• Slight casualty rates are higher on controlled (14 per hmvm) and DHS (15 per hmvm) compared to conventional motorways (10 per hmvm), while ALR roads are slightly higher (11 per hmvm)
• Serious casualty rates on controlled (1.2 per hmvm), DHS (1.2 per hmvm) and ALR (1.3 per hmvm) schemes are slightly higher to conventional motorways (1.1 per hmvm).
• Fatal casualty rates on controlled (0.07 per hmvm), DHS (0.07 per hmvm) and ALR (0.11 per hmvm) are lower than on conventional motorways (0.16 per hmvm).
• Fatal and Weighted Injury rates on controlled (0.33 per hmvm), DHS (0.33 per hmvm) and ALR (0.35 per hmvm) schemes are slightly lower than on conventional motorways (0.38 per hmvm)

Further down in the report we see that on ALR motorways breakdowns in places of relative safety have dropped while breakdowns on live lanes have increased. 40% of breakdowns on ALR motorways occur on a live lane, versus 20% on conventional motorways, 14% on controlled motorways and 24% on DHS motorways. 

Further down still:

"4.31 Turning to personal injury collisions involving a vehicle stopped in a live lane, as expected in the risk modelling, the likelihood of collisions involving a vehicle stopped in a live lane has increased. Looking at the first nine ALR schemes before and after their introduction, total live lane collisions have increased from an average of 3 per year before the ALR was introduced to an average of 19 per year after the motorway had been converted to ALR. This is broken down into: 2.3 slight, 0.3 serious and zero fatal live lane collisions on average before; and 9.1 slight, 7 serious and 2.8 fatal live lane collisions on average afterwards. This confirms the expectation in the risk modelling that there would be increased risks associated with vehicles stopping in a live lane."


Look at the statistics cited critically and the picture is rather more unclear than stated. What is obvious to obvious to me is that better signalling and better speed control improves safety on motorways. Titles that conflate the three different smart motorway types into one are not helpful. It makes sense for controlled motorways and DHS motorways to be safer than conventional motorways. ALR do appear in the statistics to be more dangerous than the other two types of smart motorway. That too makes sense.

One of their conclusions is:

"5.3 The high level statistics suggest that fatal casualty rates on the ALR network as it stands are lower, while injury rates are slightly higher. The risk modelling suggests that when converting conventional motorways to ALR, many risks decrease, while some increase. For example, the risks of a vehicle being driven too fast, and of a vehicle drifting off the carriageway, reduce whilst the risks of unsafe lane changing and of a vehicle stopping in a live lane increase. Looking at like-for-like studies of specific roads which have been converted to ALR: the overall casualty rate declines significantly; the fatal and serious casualty rate increases slightly, but within the statistical margin of error; and the FWI rate declines. The same studies further indicate that the motorway types differ in terms of the underlying risks."

In other words, covering the motorway with speed cameras makes people speed less, so we get fewer speed related casualties, making all of them variable speed limit reduces the speed differential when collisions do occur, but taking the hard shoulder out increases the amount of collisions at speeds that are not fatal.

I am totally open to corrections but the figures seem *far* more intuitive than the headlines would seem to indicate. Yes, it is more dangerous to break down on an ALR live lane than it is to break down on a hard shoulder, but overall the road is safer due to all of the other measures that have been put in place to support ALR. My unqualified opinion is that the safest way to increase capacity and safety would be conversion to DHS or at least to not have ridiculous distances between refuges in ALR.

Post edited at 22:30
 Andy Gamisou 12 Jun 2021
In reply to ianstevens:

> I mean you’re being facetious I expect but... if you are genuinely worried your vehicle might break down, then perhaps it is a good idea to do something about it?

Any vehicle can develop a fault, including brand new ones.  What steps are you suggesting to guarantee that a car I'm driving never breaks down (or gets a puncture for that matter)?

 Offwidth 13 Jun 2021
In reply to Alkis:

I'd agree with all of that: look at the data and recognise where and why ALR should be improved. The too many claiming ALR are death traps compared to old motorways are still being hyperbolic. 

As I said above it's terrifying breaking down in any live motorway lane but the risk perception of some on hard-shoulders appears closer to a safe picnic zone than high risk, while they wait for the breakdown van. There are too many bad accidents on the hard-shoulder and people should be out of the car and upstream behind the barrier ASAP.

In reply to Duncan Bourne:

What other conclusion than support for Smart Motorways could the Department for Transport researchers reach?

 Duncan Bourne 13 Jun 2021
In reply to paul__in_sheffield:

Well there is that

 fred99 11:01 Mon
In reply to paul__in_sheffield:

> What other conclusion than support for Smart Motorways could the Department for Transport researchers reach?

My thoughts entirely.

Why is it that governmental organisations, whether national or local, always do their own assessment of how good they've done something. Not only do they come to the conclusions, but they also control the collection of the data, and within the department being assessed to boot.

If they really want the results (and indeed their selves) to be trusted, then they should delegate such assessments to a completely autonomous body, that is given carte blanche to do the job.

Oh, and I don't believe that Leeds Uni actually collected the data themselves, just had data given to them that had been vetted first to ensure they'd come up with the correct answer. It's the COLLECTION of data that counts. (Garbage in = Garbage out).

Post edited at 11:03
In reply to fred99:

The data seems quite kosher, but the conclusions of the study are not quite as clear cut as either the headlines or some people here would like them to be. See my analysis above. The biggest issue is that three different kinds of motorway are all called smart. Controlled motorways are the safest motorways. Dynamic Hard Shoulder motorways trade some safety for extra capacity at peak hours but generally speaking the times when the hard shoulder would be active as a lane are the times when traffic speeds are much reduced anyway. All Lanes Running motorways trade even more safety for increased capacity, increasing the risk of live lane collisions, especially after they went cheap and increased the distance between refuge areas versus the initial pilot schemes.

The idea is that moving to a fully controlled motorway has given enough extra safety "credit" that it can be traded for extra capacity and remaining safer overall. That does not mean that somehow the obvious safety issues of having to stop on a live lane up to 2.5 miles from refuge, potentially after a gantry and with the monitors taking forever to shut the lane are not there, they very much are and the data shows this.

In reply to Offwidth:

Featured on BBC's More or less programme

https://www.bbc.co.uk/sounds/play/m000wsf0

 fred99 13:26 Mon
In reply to Alkis:

Agreed. I must admit that, having travelled on the different versions of motorway last Saturday, I did find that the original version (with a hard shoulder) was more relaxing, and my stress levels were raised on the "smart" versions.

I went home "cross-country", even though that meant going through Coventry, and found the driving much more relaxing.

 timjones 13:46 Mon
In reply to DubyaJamesDubya:

> That might be the case but does it mean the motorway is as safe as it should be.  I drive an older vehicle and  I wonder if I'm taking my life in my hands every time I go onto one of these 'cheaper' smart motorways

That will dpend on how well you maintain your older vehicle, if it is causing you concern should you be on any motorway?

 Cobra_Head 13:39 Fri
In reply to fred99:

> If they really want the results (and indeed their selves) to be trusted, then they should delegate such assessments to a completely autonomous body, that is given carte blanche to do the job.

Claire Murray and Professor Oliver Carsten did just that.
In reply to fred99:

> I went home "cross-country", even though that meant going through Coventry, and found the driving much more relaxing.

The Coventry ring road?! That thing is an abomination and freaks me out every time! Surely that cancelled out any relaxation from the rest of the journey???


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