Lower motorway speed limits

[otolith]

Mr SFJ said:

otolith said:

Yes, probably them saying that it clearly shows our NSL should be reduced from 96km/h to 90km/h!

They Replied!

@myhastag our campaign calls are based on the consensus of evidence built up over many years - not on limited individual studies.

to which I responded: @brakecharity So a 2 year study on multiple roads doesn't count as evidence? Driver training is what we need, not lower limits.

Do you know, unsurprisingly they deleted the conversation?

What a surprise. They have an obsession about speed, they won't countenance any other viewpoint.

[paranoid airbag]

dcb said:

Odd that.

Science tells us that setting the limit at the 85th percentile of what the traffic
is actually doing is the safest answer. Plenty of established science to support that setting.

For UK motorways, as measured by UK Gov, that's 82 mph. So setting the limit at
80 mph or 85 mph would actually save lives over the currently widely ignored 70 mph limit.

Plenty of examples where upping limits saved lives - USA and Denmark to name two.

It seems that yet again, the politicians demonstrate a literally lethal dose of
stupidity in ignoring the science and deciding that kicking the idea into the long
grass is a wise idea.

Shame.

I think you'll find the science says people who drive at the 85th percentile are the safest, not that setting the speed limit at the 85th is safest.

Subtle but important distinction, especially if the 85th is safest because of factors relating to your speed relative to other vehicles instead of absolute speed.
E.g. subjective, but on motorways I feel safer if I'm making my way through traffic: that way the hazards are almost always ahead of me.

That said, it's representative of a bigger principle. If a lot of people are doing something you don't want, maybe it's your part that's gone wrong. In this case, if large numbers are ignoring the speed limit either:

a)the limit is appropriate, large numbers can't or won't drive appropriately;
b)the limit is appropriate, the road design hides dangers and thus tricks even competent drivers into inappropriate speeds;
c)the limit is inappropriate.

A basic flaw in human nature leads us to overstate our competence relative to others, thus a) is disproportionately likely to be seen as the cause by the people responsible for setting the limit, something the 85th percentile idea counteracts.

[dcb]

paranoid airbag said:

I think you'll find the science says people who drive at the 85th percentile are the safest, not that setting the speed limit at the 85th is safest.

I think you are correct in point 1 and wrong in point 2.

I suggest you have a look at this for more detail:

http://www.abd.org.uk/speed_limits_85th.htm

[Mave]

dcb said:

paranoid airbag said:

I think you'll find the science says people who drive at the 85th percentile are the safest, not that setting the speed limit at the 85th is safest.

I think you are correct in point 1 and wrong in point 2.

I suggest you have a look at this for more detail:

http://www.abd.org.uk/speed_limits_85th.htm

I'm not sure that that article is particularly robust.
The shape of the speed distribution curve is assumed to be a classic bell - I don't believe this is true. The implication is that the number of cars travelling at 50mph is the same as the number travelling at 90mph.

Looking at the shape of the "risk" curve, I suspect it is an aggregate of all classes of road. Motorways are known to be the safest type of road - if you removed other road types from the curve, I expect you would see a flatter curve.

I suspect there is also an issue with speed differential between HGVs and cars - changing from lane 1 to lane 2 to pass a HGV probably influences the data, and increasing the speed limit won't change that particular risk.

[Blakewater]

The IAM have posted on Twitter links to data about how serious accident rates are increasing in 20mph limits. There are 20's Plenty campaigners going nuts in response. They're calling the IAM the "Institute of Dim Statistics," and, "A bunch of boy racers who need to grow up." It's true that it could be due to the number of 20mph limits increasing, which is their argument, but they don't appreciate that it still means introducing 20mph limits isn't reducing serious accident rates.

They seem to forget that they're supposed to be campaigning for road safety. Look at what they say and it seems to basically about wanting to control other people's lives as they go about their business.

[Vipers]

Blakewater said:

The IAM have posted on Twitter links to data about how serious accident rates are increasing in 20mph limits. There are 20's Plenty campaigners going nuts in response. They're calling the IAM the "Institute of Dim Statistics," and, "A bunch of boy racers who need to grow up." It's true that it could be due to the number of 20mph limits increasing, which is their argument, but they don't appreciate that it still means introducing 20mph limits isn't reducing serious accident rates.

They seem to forget that they're supposed to be campaigning for road safety. Look at what they say and it seems to basically about wanting to control other people's lives as they go about their business.

We need to educate the bloody pedestrians. Daily I see the usual bunch of tards at crossing, green light comes on, and they blindly cross the road, one of these days.

[GroundEffect]

Blakewater said:

The IAM have posted on Twitter links to data about how serious accident rates are increasing in 20mph limits. There are 20's Plenty campaigners going nuts in response. They're calling the IAM the "Institute of Dim Statistics," and, "A bunch of boy racers who need to grow up." It's true that it could be due to the number of 20mph limits increasing, which is their argument, but they don't appreciate that it still means introducing 20mph limits isn't reducing serious accident rates.

They seem to forget that they're supposed to be campaigning for road safety. Look at what they say and it seems to basically about wanting to control other people's lives as they go about their business.

But that's not how it works. Just because the 20-zone numbers are going up, how does that compare to the numbers of 20+30 from say 10 years ago until now? And as a rate based on cars in UK? Statistics can be twistted to anyone's viewpoint if need-be.

And I don't care about 60mph motorway limits, I usually drive around that speed anyway. Certainly in my DC2 - it's quieter and uses less fuel. Win win.

[paranoid airbag]

dcb said:

paranoid airbag said:

I think you'll find the science says people who drive at the 85th percentile are the safest, not that setting the speed limit at the 85th is safest.

I think you are correct in point 1 and wrong in point 2.

I suggest you have a look at this for more detail:

http://www.abd.org.uk/speed_limits_85th.htm

That's the exact data I'm talking about, and no, it shows no evidence at all that setting the speed limit at the 85th percentile is safest.

Sorry to be shirty but I've already explained why it doesn't and you clearly haven't listened.

[Blakewater]

GroundEffect said:

Blakewater said:

The IAM have posted on Twitter links to data about how serious accident rates are increasing in 20mph limits. There are 20's Plenty campaigners going nuts in response. They're calling the IAM the "Institute of Dim Statistics," and, "A bunch of boy racers who need to grow up." It's true that it could be due to the number of 20mph limits increasing, which is their argument, but they don't appreciate that it still means introducing 20mph limits isn't reducing serious accident rates.

They seem to forget that they're supposed to be campaigning for road safety. Look at what they say and it seems to basically about wanting to control other people's lives as they go about their business.

But that's not how it works. Just because the 20-zone numbers are going up, how does that compare to the numbers of 20+30 from say 10 years ago until now? And as a rate based on cars in UK? Statistics can be twistted to anyone's viewpoint if need-be.

And I don't care about 60mph motorway limits, I usually drive around that speed anyway. Certainly in my DC2 - it's quieter and uses less fuel. Win win.

That was the point of the people complaining, and it is a fair one if presented maturely. More 20mph limits means more stretches of road with serious accidents happening on them that fall within the 20mph bracket. Plus there are all kinds of other considerations as well. Traffic calming measures causing traffic to conflict more and potentially make life difficult for cyclists, more new housing estates with large numbers of small children residing within small areas, numbers of new drivers and elderly drivers, the safety features of cars in terms of how much they protect the occupants and the people they hit. A headline doesn't tell you the full story of what's going on. However, reducing speed limits isn't the only way to improve road safety when you have so many other things to consider and when it apparently isn't reducing serious accidents we need to look at what else can be done.

People are campaigning now for presumed liability when motorists hit pedestrians and cyclists. It doesn't mean drivers will be presumed to be legally at fault every time but it does mean insurance companies will automatically have to pay compensation to pedestrians and cyclists, no matter what they've done to end up being hit. It wouldn't be good for insurance costs even if it might help some people who genuinely do deserve compensation. http://www.roadpeace.org/change/fair_compensation/...

[vournikas]

Certainly, 20 limits in Brighton don't appear to work very well :

http://www.theargus.co.uk/news/10880794.Cycle_and_...

[Mave]

Blakewater said:

People are campaigning now for presumed liability when motorists hit pedestrians and cyclists. It doesn't mean drivers will be presumed to be legally at fault every time but it does mean insurance companies will automatically have to pay compensation to pedestrians and cyclists, no matter what they've done to end up being hit. It wouldn't be good for insurance costs even if it might help some people who genuinely do deserve compensation. http://www.roadpeace.org/change/fair_compensation/...

If you look at the magnitude of the issue, I expect the impact it would have on insurance costs is negligable; whereas the impact it would have on those deserving compensation is significant. How many people do you know who have injured a pedestrian or cyclist due to the fault of the pedestrian or cyclist, compared to those who have been in a car crash due to the fault of a motorist?

[Blakewater]

Personally I don't know anyone who's ever hit any pedestrian or cyclist. I guess, to be fair, it won't have the same effect as crash for cash scams which truly are dishonest.

[paranoid airbag]

Mave said:

Blakewater said:

People are campaigning now for presumed liability when motorists hit pedestrians and cyclists. It doesn't mean drivers will be presumed to be legally at fault every time but it does mean insurance companies will automatically have to pay compensation to pedestrians and cyclists, no matter what they've done to end up being hit. It wouldn't be good for insurance costs even if it might help some people who genuinely do deserve compensation. http://www.roadpeace.org/change/fair_compensation/...

If you look at the magnitude of the issue, I expect the impact it would have on insurance costs is negligable; whereas the impact it would have on those deserving compensation is significant. How many people do you know who have injured a pedestrian or cyclist due to the fault of the pedestrian or cyclist, compared to those who have been in a car crash due to the fault of a motorist?

I wonder... honestly, would it make a difference? From what I can tell, when insurance gets involved they usually don't contest claims against cyclists much. And let's be honest, 99% of people don't pay enough attention to the law to notice that sort of change - they'll either think what the Daily Mail or the Guardian tells them the law is.

[Pan Pan]

Speed limits are set low, to ensure the widest spectrum of driver types (and those around them) on the roads can achieve what is deemed by society to be a reasonable expectation of safety in travelling from one point to another. These limits are either natural, weather, visibility, light, or posted limits.
It seems perverse, (especially in terms of general human nature to be bringing down speeds, when the whole thrust of mankind has generally been to find ways of travelling faster, since we first became upright apes)to be taking speed limits downwards.
The main reason for being, in vehicles of any type is to travel somewhere / carry out a moving vehicle function, faster than is possible by other means.
Some of the current limits were originally imposed when vehicles had inefficient low powered engines, rod or cable operated brakes, and in some cases solid tyres.
So now we appear to have legislation which has not kept pace with advances in vehicle technology.
Of course it could be argued that current speeds are are also strongly limited by the quality of the soft squashy things around and behind the controls of a vehicle. but the current crop ops speed limits are seem to be about right for a small crowded country that wants to mix humans with vehicles in the same crowded space we call roads. Taking the limits up or down a `little' bit is unlikely to have much effect either way on road safety, but taking speeds further downwards will begin to erode the whole point of using motor vehicles. My vote would be for them to left entirely as they are, and for politicians and certain organisations to stop continually meddling with them.