Smart motorways are (not) more dangerous

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Smart motorways are (not) more dangerous

Post by hakwright » Sun Jan 26, 2020 8:01 pm

Amazingly flawed article on the BBC News website, entitled "38 killed on smart motorways in last five years" (https://www.bbc.co.uk/news/uk-51236375). It tries to make the case that smart motorways are more dangerous and cause more deaths than normal motorways.
Thirty-eight people have been killed on smart motorways in the last five years, the government has told BBC Panorama.
It is the first time that the total number of deaths has been reported.
...
There are currently 200 miles of smart motorway and another 300 miles are due to be converted by 2025.
There are around 90 deaths per year on the UK's motorway network as a whole, which covers about 2,300 miles of road.
The figure of 38 deaths over five years on the smart motorway network is significant because it only makes up a small proportion of the total miles of road.
So if you do the really-not-at-all-challenging maths, you fund that, for the 200 miles of smart motorway, if the number of deaths was following the average for the entire motorway network, you would expect about 39 deaths over 5 years. And yet the figure they quote of 38 is "significant".

So nobody bothered to do the 15-second check on the figures before publishing? Careless and irresponsible. I have already submitted a complaint to the BBC.

Howard

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Re: Smart motorways are (not) more dangerous

Post by plodder » Sun Jan 26, 2020 9:17 pm


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Re: Smart motorways are (not) more dangerous

Post by jimbob » Sun Jan 26, 2020 10:54 pm

Hi Howard and welcome.

I guess that the smart motorways are the busier stretches, so probably should have a disproportionate number of accidents.

One could compare with the previous 5 years and see if the proprtion has changed.

Also whether single multi vehicle pileups make it a noisier signal.
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Re: Smart motorways are (not) more dangerous

Post by JQH » Mon Jan 27, 2020 10:01 am

Howard's point is that the smart motorways do not have a disprportionate number of deaths. The original article as quoted compares deaths in one year for normal motorways with deaths over 5 years on smart motorways so unless you carefully parse it you are comparing 38 deaths on 200 miles with 90 deaths on 2300 miles - which sounds pretty bad. Sloppy writing or intent to mislead?
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Re: Smart motorways are (not) more dangerous

Post by Bugs » Mon Jan 27, 2020 10:26 am

Point 1 deaths per 200 miles (current) of "smart motorway" quoted over 5 years, so how many miles of "smart motorway" were there in year 1 of 5 , year 2 of 5 etc. My local "smart motorway" the M3 has a stretch of this but certainly hasn't been open for all of those 5 years, the 26 mile stretch was opened in June 2017, that accounts for 13% of smart motorway miles.
Point 2 having been the next car back from a near miss of a parked car I know it's bl..dy scary, as my son says "What could possibly go wrong!"

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Re: Smart motorways are (not) more dangerous

Post by Martin Y » Mon Jan 27, 2020 11:34 am

Bugs wrote:
Mon Jan 27, 2020 10:26 am
Point 1 deaths per 200 miles (current) of "smart motorway" quoted over 5 years, so how many miles of "smart motorway" were there in year 1 of 5 , year 2 of 5 etc. My local "smart motorway" the M3 has a stretch of this but certainly hasn't been open for all of those 5 years, the 26 mile stretch was opened in June 2017, that accounts for 13% of smart motorway miles.
Point 2 having been the next car back from a near miss of a parked car I know it's bl..dy scary, as my son says "What could possibly go wrong!"
That's a good point: the current 200 miles of smart motorway has not all been operating for 5 years. The only other statistic presented is one (outlier?) stretch of the M25 with an enormous increase in "near misses" (however that is measured). We just don't have enough information to see how valid the concerns are, but I see a report is due out tomorrow. Let's hope it's informative though it may prove to be something of an arse-covering exercise by Mike Penning, the minister who gave the project the go-ahead.

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Re: Smart motorways are (not) more dangerous

Post by Martin Y » Mon Jan 27, 2020 11:54 am

There's also perhaps confusion over what "smart motorway" describes.

Most of the M25 is "smart motorway" but the greater part of that just has variable speed limits. I think the safety concerns are over versions of smart motorway which sometimes allow traffic to use the hard shoulder when traffic is heavy or which have no hard shoulder and only close the inside lane if there's a breakdown causing an obstruction.

Map of the current state here: https://assets.publishing.service.gov.u ... 54_MGW.PDF

Just judging that map by eye (and estimating London-Leeds = 200 miles) I think the quoted 200 miles of active smart motorway excludes the variable speed limit stuff but I'm far from certain.

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Re: Smart motorways are (not) more dangerous

Post by Matatouille » Mon Jan 27, 2020 12:05 pm

I wonder how near-misses are counted. Does it require a near-miss-ee to call a number to specifically report it, or from monitoring cameras etc? I might be a near-miss statistic, or I might be just an unknown person who had an uncounted near miss, because I nearly hit a car pulled over at night on the left lane on a section of M1 smart motorway, but I didn't specifically report it myself.

As such, I flipped from being broadly instinctively supportive of Smart Motorways to instinctively suspicious of them pretty much immediately. I'd love to see a sound analysis of what the numbers say to see which versions of my instinctive stances is more correct, shame that BBC article doesn't appear to be it. Lets see if today's report is any better.

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Re: Smart motorways are (not) more dangerous

Post by tenchboy » Mon Jan 27, 2020 12:51 pm

The hard shoulder has always been your safe zone: and even then only your safest zone; you pull up, get out, move away as far as possible and hope all goes well. Even allowing for that they are still dangerous places to be - maybe - I have no figures - the most dangerous places to be. Your only hope is to be rescued before a truck drifts onto the hard shoulder and crashes into your broken down car or recovery worker.

Handbrake on. Get out.

And someone thought it was a good idea to let traffic use the hard shoulder travelling - presumably - at 70mph? And still expect people to pull over when broken down? You would be safer stopping in lane 2 so that other drivers could pass either side.
I don't travel much these days, not like I used to; I had no idea it was going on. I am sitting here in utter, utter disbelief!

To assess this story properly we need figures for hard shoulder accidents to be separated from moving traffic - lane 1,2,3 - accidents.

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Re: Smart motorways are (not) more dangerous

Post by tenchboy » Mon Jan 27, 2020 12:53 pm

tenchboy wrote:
Mon Jan 27, 2020 12:51 pm
The hard shoulder has always been your safe zone: and even then only your safest zone; you pull up, get out, move away as far as possible and hope all goes well. Even allowing for that they are still dangerous places to be - maybe - I have no figures - the most dangerous places to be. Your only hope is to be rescued before a truck drifts onto the hard shoulder and crashes into your broken down car or recovery worker.

Handbrake on. Get out.

And someone thought it was a good idea to let traffic use the hard shoulder travelling - presumably - at 70mph? And still expect people to pull over when broken down? You would be safer stopping in lane 2 so that other drivers could pass either side.
I don't travel much these days, not like I used to; I had no idea this was going on. I am sitting here in utter, utter disbelief!

To assess this story properly we need figures for hard shoulder accidents to be separated from moving traffic - lane 1,2,3 - accidents.

Edit to change it to this

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Re: Smart motorways are (not) more dangerous

Post by jaap » Mon Jan 27, 2020 1:08 pm

tenchboy wrote:
Mon Jan 27, 2020 12:51 pm
And someone thought it was a good idea to let traffic use the hard shoulder travelling - presumably - at 70mph? And still expect people to pull over when broken down? You would be safer stopping in lane 2 so that other drivers could pass either side.
I don't travel much these days, not like I used to; I had no idea it was going on. I am sitting here in utter, utter disbelief!
This has been done in the Netherlands for donkey's years. It is perfectly fine.

On some motorways the hard shoulder gets used as an extra lane during rush hours, as indicated by the green arrows on the overhead light signage. This is only done when it is really busy. If someone breaks down (which nowadays really does not happen very often) they will slow down to a stop, and there will be an almost immediate tailback. The cameras and the sensors in the road pick this up, the signage is changed so that the lane is closed and the adjacent lanes get a speed restriction. It is really not a problem*.

Even when the hard shoulder is not open as a traffic lane, when someone stops on it, the cameras pick it up, and the adjacent lane gets a speed restriction or gets closed.

* Provided people actually comply with the signage. The fines for ignoring a red cross of a closed lane has recently been increased massively.

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Re: Smart motorways are (not) more dangerous

Post by Gfamily » Mon Jan 27, 2020 1:11 pm

Matatouille wrote:
Mon Jan 27, 2020 12:05 pm
I wonder how near-misses are counted. Does it require a near-miss-ee to call a number to specifically report it, or from monitoring cameras etc? I might be a near-miss statistic, or I might be just an unknown person who had an uncounted near miss, because I nearly hit a car pulled over at night on the left lane on a section of M1 smart motorway, but I didn't specifically report it myself.

As such, I flipped from being broadly instinctively supportive of Smart Motorways to instinctively suspicious of them pretty much immediately. I'd love to see a sound analysis of what the numbers say to see which versions of my instinctive stances is more correct, shame that BBC article doesn't appear to be it. Lets see if today's report is any better.
I think I read that there's radar monitoring on part of the M25 and that can remotely detect near-misses, as well as notifying broken down vehicles blocking lanes in seconds rather than minutes if depending on drivers to get in touch. (I read 17 minutes somewhere, whether that's average or 'up to', I'm not sure)

When a vehicle is known to be blocking a lane the matrix signs can be set to the red X.
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Re: Smart motorways are (not) more dangerous

Post by Martin Y » Mon Jan 27, 2020 1:14 pm

Anecdata ahoy.

My personal experience of UK motorways is that compliance with red crossed lanes on motorways here is really not good. They've been around since the '70s in some places but people still treat them as "advisory". Behaviour is perhaps getting better than it was, but nothing like so effective as, say, average speed check zones which are pretty much universally obeyed.

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Re: Smart motorways are (not) more dangerous

Post by Boustrophedon » Mon Jan 27, 2020 1:16 pm

I have broken down in lane 2, right where the M25 joins the M1, so actually in the middle lane of 5 or six lanes. I got the f.ck out as soon as I could and ran for the safety of the hard shoulder and over the barrier.

The thought of being broken down on a hard shoulder that is an active lane scares me. On smart Motorways the carriageway is monitored by CCTV every 100m or so, the idea being that in the event of a broken down car they can use the traffic lights to divert traffic off the hard shoulder.
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Re: Smart motorways are (not) more dangerous

Post by Martin Y » Mon Jan 27, 2020 1:21 pm

Gfamily wrote:
Mon Jan 27, 2020 1:11 pm
… I think I read that there's radar monitoring on part of the M25 and that can remotely detect near-misses, as well as notifying broken down vehicles blocking lanes in seconds rather than minutes if depending on drivers to get in touch. (I read 17 minutes somewhere, whether that's average or 'up to', I'm not sure)
BBC article in the OP quotes 17 minutes average.

Breakdowns are rare these days but I do worry that just getting over to the hard shoulder when you realise something's wrong is made harder if you're trying to get across into a lane which also has traffic in it, and then you have several minutes where the approaching traffic has no advance warning of your stranded vehicle.

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Re: Smart motorways are (not) more dangerous

Post by lpm » Mon Jan 27, 2020 1:42 pm

jaap wrote:
Mon Jan 27, 2020 1:08 pm
tenchboy wrote:
Mon Jan 27, 2020 12:51 pm
And someone thought it was a good idea to let traffic use the hard shoulder travelling - presumably - at 70mph? And still expect people to pull over when broken down? You would be safer stopping in lane 2 so that other drivers could pass either side.
I don't travel much these days, not like I used to; I had no idea it was going on. I am sitting here in utter, utter disbelief!
This has been done in the Netherlands for donkey's years. It is perfectly fine.

On some motorways the hard shoulder gets used as an extra lane during rush hours, as indicated by the green arrows on the overhead light signage. This is only done when it is really busy. If someone breaks down (which nowadays really does not happen very often) they will slow down to a stop, and there will be an almost immediate tailback. The cameras and the sensors in the road pick this up, the signage is changed so that the lane is closed and the adjacent lanes get a speed restriction. It is really not a problem*.

Even when the hard shoulder is not open as a traffic lane, when someone stops on it, the cameras pick it up, and the adjacent lane gets a speed restriction or gets closed.

* Provided people actually comply with the signage. The fines for ignoring a red cross of a closed lane has recently been increased massively.
In the UK there are some motorways like this - hard shoulder is an extra lane in rush hours.

But there are also permanent conversions - a three lane + hard shoulder motorway has become a four lane + no hard shoulder motorway.

The risks are different. In the first, you can have a 50mph speed limit and/or queues. Drivers are generally primed to expect brake lights ahead of them and traffic slowing down; a stranded car will cause tailbacks and cars will be squeezing out of the blocked lane slowly.

In the second, you have 70mph limit and anti-social c.nts driving at >70 mph, and the road can be almost empty. Drivers are not primed to expect a blocked lane.
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Re: Smart motorways are (not) more dangerous

Post by El Pollo Diablo » Mon Jan 27, 2020 3:35 pm

TBF, the anti social c.nts on a near-empty motorway will all be in lane 2.
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Re: Smart motorways are (not) more dangerous

Post by El Pollo Diablo » Mon Jan 27, 2020 3:37 pm

I'm interested in the capturing of data around near misses. Do pre-smart motorways have the same ability to record near misses as a motorway which has a large set of cameras every several hundred metres?
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Re: Smart motorways are (not) more dangerous

Post by plodder » Mon Jan 27, 2020 3:49 pm

El Pollo Diablo wrote:
Mon Jan 27, 2020 3:35 pm
TBF, the anti social c.nts on a near-empty motorway will all be in lane 2.
So in an equitable world, that's where you'd park the broken down motorhomes?

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Re: Smart motorways are (not) more dangerous

Post by Gfamily » Mon Jan 27, 2020 3:57 pm

El Pollo Diablo wrote:
Mon Jan 27, 2020 3:35 pm
TBF, the anti social c.nts on a near-empty motorway will all be in lane 2.
/ Lane 3 if there are 4 or more.
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Re: Smart motorways are (not) more dangerous

Post by Martin Y » Mon Jan 27, 2020 4:30 pm

Gfamily wrote:
Mon Jan 27, 2020 3:57 pm
El Pollo Diablo wrote:
Mon Jan 27, 2020 3:35 pm
TBF, the anti social c.nts on a near-empty motorway will all be in lane 2.
/ Lane 3 if there are 4 or more.
Having a lane 1 that you can't always use provides a perfect illustration of my conjecture that most drivers, most of the time, are simply not concentrating at all.
  • Lane 1 is sometimes the hard shoulder: nobody uses it because they're not 100% sure what that sign back there said and nobody else is using it so maybe there's something I didn't understand about "use hard shoulder".
  • Lane 1 is a bus lane during rush hour: nobody uses it because oh was there a sign I didn't see it […] gosh here's another right at the end says the bus lane doesn't operate between 10 and 4 what time is it again are you sure?
  • Lane 1 peels off at one junction: nobody uses it because they don't want to get trapped in a lane that turns off the motorway especially here there are some really rough places around here and I'm pretty sure it's along here somewhere or maybe we passed it 20 miles back but better safe than sorry.

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Re: Smart motorways are (not) more dangerous

Post by RandomElement » Mon Jan 27, 2020 5:17 pm

lpm wrote:
Mon Jan 27, 2020 1:42 pm
jaap wrote:
Mon Jan 27, 2020 1:08 pm
tenchboy wrote:
Mon Jan 27, 2020 12:51 pm
And someone thought it was a good idea to let traffic use the hard shoulder travelling - presumably - at 70mph? And still expect people to pull over when broken down? You would be safer stopping in lane 2 so that other drivers could pass either side.
I don't travel much these days, not like I used to; I had no idea it was going on. I am sitting here in utter, utter disbelief!
This has been done in the Netherlands for donkey's years. It is perfectly fine.

On some motorways the hard shoulder gets used as an extra lane during rush hours, as indicated by the green arrows on the overhead light signage. This is only done when it is really busy. If someone breaks down (which nowadays really does not happen very often) they will slow down to a stop, and there will be an almost immediate tailback. The cameras and the sensors in the road pick this up, the signage is changed so that the lane is closed and the adjacent lanes get a speed restriction. It is really not a problem*.

Even when the hard shoulder is not open as a traffic lane, when someone stops on it, the cameras pick it up, and the adjacent lane gets a speed restriction or gets closed.

* Provided people actually comply with the signage. The fines for ignoring a red cross of a closed lane has recently been increased massively.
In the UK there are some motorways like this - hard shoulder is an extra lane in rush hours.

But there are also permanent conversions - a three lane + hard shoulder motorway has become a four lane + no hard shoulder motorway.

The risks are different. In the first, you can have a 50mph speed limit and/or queues. Drivers are generally primed to expect brake lights ahead of them and traffic slowing down; a stranded car will cause tailbacks and cars will be squeezing out of the blocked lane slowly.

In the second, you have 70mph limit and anti-social c.nts driving at >70 mph, and the road can be almost empty. Drivers are not primed to expect a blocked lane.

Most of my experience is with the M3 which is the 70mph All Lane Running type. Not only there are problems LPM highlighted, but there is also a lot of the ALR stretch where the crash barrier is next to the carriageway, so you can't even get 1/2 the car off the running lane, plus at Junction 4a (I think) and others too, the additional (old hard shoulder) lane is the slip road for the junction so you get people swerving out not to go down the wrong lane. It feels a lot more dangerous. On the M6 before the M6/M42 interchange they have the type Jaap refers to which is a good way of increasing traffic at peak times. Whether or not this is reflected in the data would be interesting to know.

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Re: Smart motorways are (not) more dangerous

Post by hakwright » Tue Jan 28, 2020 1:19 pm

Bugs wrote:
Mon Jan 27, 2020 10:26 am
Point 1 deaths per 200 miles (current) of "smart motorway" quoted over 5 years, so how many miles of "smart motorway" were there in year 1 of 5 , year 2 of 5 etc. My local "smart motorway" the M3 has a stretch of this but certainly hasn't been open for all of those 5 years, the 26 mile stretch was opened in June 2017, that accounts for 13% of smart motorway miles.
True. If you make the (unrealistic) assumption that there have been 200 miles of smart motorway for 5 years, this gives the maximum number of deaths expected - assuming that the death rate is the same for smart motorways as the rest of the motorway network.

If you do this, you find that you'd expect 39 deaths on smart motorways over 5 years.

Without knowing how the total number of miles of smart motorway has evolved over 5 years, it's hard to do a better calculation. Presumably it will give you a somewhat lower result - but we don't know if significantly lower, hence we can't judge whether the recorded figure of 38 is outside the expected range or not. But the article makes a strong claim that 38 *is* unusually high - but without the data to back this up.

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Re: Smart motorways are (not) more dangerous

Post by Fishnut » Tue Jan 28, 2020 1:56 pm

Has anyone been able to find the report that the Guardian said should be published today? I've looked but can't find anything. PoliticsHome also says that should be published today but the Campaign for Safer Roadside Rescue and Recovery which is, I think, the organisation that should be publishing the report, has nothing but and I can't see any tweets about it.

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Re: Smart motorways are (not) more dangerous

Post by Martin Y » Tue Jan 28, 2020 2:00 pm

Fishnut wrote:
Tue Jan 28, 2020 1:56 pm
Has anyone been able to find the report that the Guardian said should be published today? I've looked but can't find anything. PoliticsHome also says that should be published today but the Campaign for Safer Roadside Rescue and Recovery which is, I think, the organisation that should be publishing the report, has nothing but and I can't see any tweets about it.
I can't find it. I just ended up watching the Panorama episode the BBC article links to but, other than confirming you found the right organisation, it doesn't add much information.

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