Tag Archives: speed

Repost: Exclusive: things tend to have a greater effect on the world once they exist

So the Institute of Advanced Motorists have press released the fact that casualties are up on 20mph streets (deaths are down, but they were already in single figures, so that’s random). I thought it might be worth reposting this sarcastic rubbish that I bashed out last time some idiot tried to claim that an increase in casualties on 20mph roads is evidence of their failure.

I heard on the lunchtime news on Radio 4 today the shocking news of an increase in the number of people injured on 20mph streets. Back when there were fewer 20mph streets, fewer people were injured on 20mph streets, they revealed. Now that there are more 20mph streets, more people are being injured on 20mph streets. This road safety intervention, they concluded, isn’t working.

This watertight logic perhaps also explains why BBC News have been so quiet on the destruction of the NHS. Before the NHS existed, literally nobody at all died in any of the then non-existent NHS hospitals. Almost as soon as the NHS was created, people started dying in the newly created NHS hospitals. Clearly the NHS doesn’t work.

Members of the Association of British Nutters will no doubt be getting very excited about these numbers, but before they make rash recommendations they should remember that back before the British motorway network was built, there were literally no people injured on the British motorway network, whereas now that the British motorway network exists, there are lots.

I hope that the main elements of the astonishing innumeracy that went into the BBC story — the failure to put the raw numbers into any kind of useful context, either of the rapid growth in the number of streets with 20mph limits as it has become easier to set the limit (or their changing nature as 20mph starts to roll out beyond quiet residential streets onto busier high streets), or of the far higher number (and, more importantly, rate) of injuries and death on either equivalent 30mph streets or on the same 20mph streets before the speed was lowered — should be obvious. Needless to say, reducing speeds on a street from 30mph to 20mph cuts injuries, regardless of the entirely banal fact that those few injuries which remain will thenceforth be added to the tally for 20mph streets instead of that for 30mph.

So, mockery over,  there’s a more important point: should an increase in injuries, if there really had been one, automatically kill off further roll out of 20mph zones?

Those who dwell at the bottom of Bristol’s Evening Post presumably think so

It beggars belief that the council intend reducing the 30mph speed limit. A limit introduced when there was no such thing as MoT’s, ABS brakes, crash zones on the front of cars and good street lighting.

I can see no justification in spending this money and would dearly love to know who Bristol City Council think it will benefit? It certainly won’t be the youth, disabled or elderly.

James R Sawyer clearly thinks that the 20 zones must be all about safety, as he argues that his ABS brakes and crash zones are already plenty enough to keep him safe as he drives through Bristol at 30. But Bristol have always been clearabout why they’re moving towards a 20mph city:

Councillor Jon Rogers, Cabinet Member for Care and Health, said: “…20 mph zones create cleaner, safer, friendlier neighbourhoods for cyclists and pedestrians. They are popular with residents, as slower traffic speeds mean children can play more safely and all residents can enjoy calmer environment.”

Slower speeds are not a simple issue of cutting crude injury statistics. They’re more about reviving communities which have been spoiled and severed by traffic speeding through them, reclaiming a little bit of the public realm that has been monopolised by the motorcar, and enabling liveable walkable neighbourhoods to thrive. Far from “certainly no benefit for the youth, disabled or elderly”, we know much — some of the research having in fact been carried out in Bristol itself — about the many adverse effects of higher speeds and volumes of traffic, and the loss of shops and services due to car-centric planning and living and the blight of high streets by arterial traffic, on the mobility of those most excluded from the car addicted society, particularly the young, the elderly, and the disabled. If they’re lucky, these people will be forced into dependency on those willing to help them get around; if they’re unlucky, they will simply be left isolated and severely disadvantaged. But of course, we don’t like to acknowledge the existence of the large numbers of people who are excluded from much of our society, culture and economy by our rebuilding the world with nobody in mind except car owners.

The injury statistics cited in the BBC News piece include minor injuries, which is most injuries at slow speeds — little things which don’t require a hospital stay. What are a few more cuts and bruises if it means that thousands of kids are free to walk to school with their friends instead of stuck inside mum’s car? Would we rather keep the infirm all shut up and sedentary with no access to the shops and the services they need, too intimidated by the anti-social behaviour of motorists to cross the road, than risk one person having a fall?

These strands can be tied together by the other piece of context that would have been worth including in the BBC piece: in the same year that injuries in 20mph zones increased, injuries to pedestrians and cyclists in general increased — in part because there are more to be injured. It has always been the case that the great road safety gains that successive governments have boasted of have been won mainly by making streets so dreadful that people find them too frightening, stressful, unpleasant, humiliating or ineffective to walk, cycle, or do anything other than sit in a secure metal box on. Start making the streets a little bit less awful and people return to them.

“The overall results show that ‘signs only’ 20mph has been accompanied by a small but important reduction in daytime vehicle speeds, an increase in walking and cycling counts, especially at weekends, a strengthening of public support for 20mph, maintenance of bus journey times and reliability, and no measurable impact on air quality or noise.”

Like cycle tracks, which people still like to claim increase car-cycle collisions (they don’t) despite before-and-after studies largely ignoring the fact that the point of cycle tracks is to widen bicycle use from the confident and quick witted to the people who were are otherwise too scared, stressed or infirm to do so, so invalidating the before-and-after study design, an increase in minor injuries after speed limit reduction, even if it were really to happen, would be far from proof of a failure.

Postscript, July 2014

The IAM make a thing of the DfT stats showing a 26% increase in serious injuries in 20mph limits and a 9% decrease in 30mph limits. Given that the base figures for the two sets are so different, that amounts to 87 more injuries in 20 zones and 1102 fewer injuries in 30 zones. Of course, the only figures that would really matter (in the absence of a double blind randomised controlled trial) are before/after comparisons of the streets that have switched and/or case-control studies of those streets (at least, for measuring injuries; as I said before, there are other important outcomes to 20 zones besides injury rates). And given that these numbers are not (and could not really be) normalised to the changes in total length of the two types of street, and are influenced by far too many confounding variables, I wouldn’t dream of suggesting that they’re worth drawing any conclusion from. But if you’re intent on drawing a conclusion, given the trend in switching 30mph streets to 20mph streets, a net reduction in serious injuries of 1015 seems like a far more pertinent one than a 26% increase in injuries on 20mph streets.

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A double-blind trial of 20mph speed limits is an excellent idea

Association of British Drivers chairman Brian Gregory had this to say: “As with most pet road safety ideas proposed by amateur enthusiasts – speed humps, speed cameras, etc, – there is little attempt to collect scientifically sound evidence of the benefit of such ideas. No proper controlled, “double-blind” trials are undertaken…

Brian Gregory is absolutely right. Too many of our transport policies — everything from encouraging the wearing of bicycle helmets to attempting to “smooth traffic flow” in cities — are based on weak evidence and poor quality research, and many of them would benefit from well designed trials.

In particular, a proper double-blind randomised controlled trial of 20mph speed limits would be very welcome. I’m sure you can see how it would be designed.

First we take every residential neighbourhood in the country and split them randomly into “test” and “control” neighbourhoods. It’s double-blind, meaning that the boffins doing the stats should know only that there are two groups, and be “blind” to which one the test has been applied to until after they’ve finished crunching the numbers and determined which group of neighbourhoods came out best.

Then we give all of the test subjects (that is, residents, pedestrians, cyclists, children, the local economy, and anybody/thing else expected, according to the hypothesis, to benefit) the treatment — 20mph speed limits for their neighbourhood. Except that only those in the test neighbourhoods get the active ingredient; in the control neighbourhoods, they receive an inert placebo. It’s double-blind, meaning that these subjects must not know whether they are receiving the active treatment or the placebo.

The active ingredient, of course, is reduced speeds. So we have to implement the active ingredient in the test neighbourhoods while maintaining blinding amongst the test subjects. Easy enough, of course: fit to every vehicle a simple computer which recognises when it is in a test neighbourhood and limits the vehicle’s speed to 20mph in those areas. In the control neighbourhoods, the motorists should continue driving as they usually do at 35mph.

I’m sure that’s exactly what Brian Gregory must have had in mind, and it’s great to see the Association of British Drivers campaigning for this.

Exclusive: things tend to have a greater effect on the world once they exist

I heard on the lunchtime news on Radio 4 today the shocking news of an increase in the number of people injured on 20mph streets. Back when there were fewer 20mph streets, fewer people were injured on 20mph streets, they revealed. Now that there are more 20mph streets, more people are being injured on 20mph streets. This road safety intervention, they concluded, isn’t working.

This watertight logic perhaps also explains why BBC News have been so quiet on the destruction of the NHS. Before the NHS existed, literally nobody at all died in any of the then non-existent NHS hospitals. Almost as soon as the NHS was created, people started dying in the newly created NHS hospitals. Clearly the NHS doesn’t work.

Members of the Association of British Nutters will no doubt be getting very excited about these numbers, but before they make rash recommendations they should remember that back before the British motorway network was built, there were literally no people injured on the British motorway network, whereas now that the British motorway network exists, there are lots.

I hope that the main elements of the astonishing innumeracy that went into the BBC story — the failure to put the raw numbers into any kind of useful context, either of the rapid growth in the number of streets with 20mph limits as it has become easier to set the limit (or their changing nature as 20mph starts to roll out beyond quiet residential streets onto busier high streets), or of the far higher number (and, more importantly, rate) of injuries and death on either equivalent 30mph streets or on the same 20mph streets before and after the speed was lowered — should be obvious. Needless to say, reducing speeds on a street from 30mph to 20mph cuts injuries, regardless of the entirely banal fact that those few injuries which remain will thenceforth be added to the tally for 20mph streets instead of that for 30mph.

So, mockery over,  there’s a more important point: should an increase in injuries, if there really had been one, automatically kill off further roll out of 20mph zones?

Those who dwell at the bottom of Bristol’s Evening Post presumably think so

It beggars belief that the council intend reducing the 30mph speed limit. A limit introduced when there was no such thing as MoT’s, ABS brakes, crash zones on the front of cars and good street lighting.

I can see no justification in spending this money and would dearly love to know who Bristol City Council think it will benefit? It certainly won’t be the youth, disabled or elderly.

James R Sawyer clearly thinks that the 20 zones must be all about safety, as he argues that his ABS brakes and crash zones are already plenty enough to keep him safe as he drives through Bristol at 30. But Bristol have always been clear about why they’re moving towards a 20mph city:

Councillor Jon Rogers, Cabinet Member for Care and Health, said: “…20 mph zones create cleaner, safer, friendlier neighbourhoods for cyclists and pedestrians. They are popular with residents, as slower traffic speeds mean children can play more safely and all residents can enjoy calmer environment.”

Slower speeds are not a simple issue of cutting crude injury statistics. They’re more about reviving communities which have been spoiled and severed by traffic speeding through them, reclaiming a little bit of the public realm that has been monopolised by the motorcar, and enabling liveable walkable neighbourhoods to thrive. Far from “certainly no benefit for the youth, disabled or elderly”, we know much — some of the research having in fact been carried out in Bristol itself — about the many adverse effects of higher speeds and volumes of traffic, and the loss of shops and services due to car-centric planning and living and the blight of high streets by arterial traffic, on the mobility of those most excluded from the car addicted society, particularly the young, the elderly, and the disabled. If they’re lucky, these people will be forced into dependency on those willing to help them get around; if they’re unlucky, they will simply be left isolated and severely disadvantaged. But of course, we don’t like to acknowledge the existence of the large numbers of people who are excluded from much of our society, culture and economy by our rebuilding the world with nobody in mind except car owners.

The injury statistics cited in the BBC News piece include minor injuries, which is most injuries at slow speeds — little things which don’t require a hospital stay. What are a few more cuts and bruises if it means that thousands of kids are free to walk to school with their friends instead of stuck inside mum’s car? Would we rather keep the infirm all shut up and sedentary with no access to the shops and the services they need, too intimidated by the anti-social behaviour of motorists to cross the road, than risk one person having a fall?

These strands can be tied together by the other piece of context that would have been worth including in the BBC piece: in the same year that injuries in 20mph zones increased, injuries to pedestrians and cyclists in general increased — in part because there are more to be injured. It has always been the case that the great road safety gains that successive governments have boasted of have been won mainly by making streets so dreadful that people find them too frightening, stressful, unpleasant, humiliating or ineffective to walk, cycle, or do anything other than sit in a secure metal box on. Start making the streets a little bit less awful and people return to them.

“The overall results show that ‘signs only’ 20mph has been accompanied by a small but important reduction in daytime vehicle speeds, an increase in walking and cycling counts, especially at weekends, a strengthening of public support for 20mph, maintenance of bus journey times and reliability, and no measurable impact on air quality or noise.”

Like cycle tracks, which people still like to claim increase car-cycle collisions (they don’t) despite before-and-after studies largely ignoring the fact that the point of cycle tracks is to widen bicycle use from the confident and quick witted to the people who were are otherwise too scared, stressed or insecure to do so, so invalidating the before-and-after study design, an increase in minor injuries after speed limit reduction, even if it were really to happen, would be far from proof of a failure.

Weekly War Bulletin, 1 Jan

A rollover bulletin…

Apparently some people had holiday journeys disrupted by snow?  The civil servants are having fun suggesting technical solutions to the third-rail problem — some more expensive than others.  (Not that the overhead-electric east coast route did any better: the lines came down under the weight of ice; I have vague memories of being told that the line was built with a larger than recommended distance between gantries to save money, in the knowledge that this would mean the cables would fall down more readily.)  Guess it’ll be another fares hike to pay for that, if it ever happens, then.  Can’t have anyone suggesting that we should instead be investing in arranging our lives and economy in a less mobility-reliant way.  Meanwhile, from his bunker, the mayor boasted about London’s resilient transport network even as it predictably ground to a halt.

The weather turned out to be awfully convenient for SouthEastern, who, having called an emergency and cancelled their trains, had the snow days struck from their performance records and subsequently just happened to meet their targets by the tiniest sliver, thus avoiding compensating season ticket holders.

Philip Hammond’s Department for Transport don’t care about the thousands of known dangerous drivers on the roads.  Our judges seem to think that it’s their job to facilitate the truck driver training careers of convicted road-rage attackers.  And the police seem to think that pushing somebody under an oncoming vehicle is fine if they’re a cyclist.  That’s The War On The Motorist, that is.  Just compare the authorities’ actions to those in The War On Drugs.

And the latest reform of road safety initiatives mean that you will no-longer get fined if you only go 10%+9mph over the limit — because what harm could you possibly do at 41 in a built-up area?  As one Daily Mail reader points out, this is “yet another money-gouging racket at the motorist’s expense”.

The Western Extension Zone is no more: Boris promised to obey the people’s will, and 41% of people wanted the WEZ to go, so the numerically challenged mayor (elected by the will of 24.1% of the electorate) obeyed.  The removal of the WEZ, and loss of its £55m revenue, will be funded by the £60m raised by another bus fare hike.

It’s time for those fares increases.  Up to £5,000 season tickets on some routes — though frankly, if you find yourself in the situation where you need to do a £5,000 commute, I think you might be doing something wrong.  Predictions are for a shift from rail to private car,

Fuel duty and VAT also go up this week, though, so it’s still a good time to leave the car behind.  The Express are desperately trying to stir up the resistance.  The Institute of Advanced Motorists is suggesting that, gasp, Motorists might be forced to drive at responsible speeds in order to save fuel, while RMI beg us please won’t somebody think of the petrol stations?

Fake ban on cycling to be enforced by fake police on the South Bank.

Government to publish data on where most people are recklessly breaking the law they are having greatest success at bleeding the poor innocent hard done-by Motorist dry. (c) All Newspapers.

Awww.  Poor Motorists can’t even terrorise sick people by taking short-cuts through hospital car parks without getting hassle some jobsworth.  It’s The War On The Motorist, I tell you.

Absurd solution of the week: Maria Eagle thinks we should pay Motorists not to break the law.  I think there is great potential here for basing all of post-New Labour’s manifesto on this concept.

Speaking of absurd transport solutions, last Bulletin we noted that the absurd Royal Docks cable car would not be entirely privately funded as Boris had originally promised.  Now our suspicions have been confirmed: upon further investigation, estimated costs jump from £25m to £40m, and there is no chance of being built before the mayor’s Olympic deadline.

Could we please drop this folly now and divert the money to keeping our existing river crossings open?  Greenwich Tunnel, the nearest existing crossing (excluding tubes and the motor-only Blackwall Tunnel), is plagued by unscheduled closures due to maintenance problems, with the council and contractors providing a customer service that they surely learnt from SouthEastern.

People got to travel on the tube for free last night, courtesy of a loans company that charges 2,689% interest.  When grilled by LBC, Boris called it extortion, as he happily took the money that they had obtained by extortion.

Humankind has reached the stage where it has developed computers that can be aware of the emotional state of the people using them.  What noble purpose should we find for this technology?  Satnavs that don’t upset their poor sensitive drivers, of course.  Somebody get one for this guy.

Following the earlier news that ELL passenger numbers have risen fast, and the recent introduction of the full timetable, Ian Brown — the man who organised London Overground and had great visions for the public takeover of all suburban rail in London under TfL — is honoured.

Tory campaigners are trying to distract from Boris Johnson’s failure to resolve the problems that unions are striking over by accusing the unions of calling strikes merely to make the mayor look bad.

That Oxford coach that turned over on the motorway? A drunk passenger done it.

The police have been visiting the people selling stolen bikes at Brick Lane.

Careful now.  Cabbies have learned dozens of new ways to kill you.

More plans for congestion relief at Bank.

New York consider adding bicycle training to their driving test.

This “news” is written by “Ian Onions”, which is a delightful combination of syllables.

Weekly War Bulletin, 18 Sep

This week, a report by Professor Obvious, commissioned by the Department for Transport, found that Motorists feel a great sense of entitlement to the road and will throw their toys around when they don’t get what they think they’re owed.  Like the van driver who cut out in front a cyclist, threw a bottle when the cyclist pointed out the quality of the driving on show, and subsequently got fined because it was all on film.  This last development is likely to alarm the readers of the Daily Mail who, usually so keen to dictate how others should behave, are getting rather worried about Sussex police’s plans to Big Societise traffic policing, with the public encouraged to report each-other’s bad behaviour on the road.

George Michael “gasped” when told he was to be locked up for a mere four weeks, having admitted getting wasted on what the BBC delightfully describes as “cannabis cigarettes” and driving his three ton truck around central London — by pure good fortune crashing it into a Snappy Snaps before he could drive it into a person.  We share your astonishment, George.

Two young offenders have fled detention on their cycle proficiency bikes.  Their choice of getaway vehicle is yet more evidence, as though it were needed, that cyclists are selfish, anti-social, holier-than-thou, road-hogging pavement thieves.

RoadPeace are fighting against those in the “road safety” industry who will try to blame the deaths on our streets on anything — headphones, poverty, texting — except cars and drivers.

But: it turns out that breaking the speed-limit is officially morally OK after all, because the government lied about how likely you are to kill a child at 40mph.

And the London Cycling Campaign want to spend £20,000 on posters asking people nicely if they wouldn’t mind just being a bit safer when they drive their lethal vehicles around entirely inappropriate streets.

Permission to pave a cycle path in Putney Common is denied because of a rule that the area must be kept natural and free from human influence.  A3 dual-carriageway is exempt from that rule for obvious reasons.

Nobody uses TfL’s guided rides to work.

Mayor makes special arrangements for pampered director of centuries-old wealth-hoarding organisation to get driven around London without paying the CCharge.

Not really news, but the Telegraph has some impressively large contextless numbers on the copper-wire theft that is the cause of signalling failures.

This week saw the first casualty of note on a hire bike.  More interestingly, the Standard now seems to think that the hire bikes are known by a compound noun, “Borisbikes”.

The Campaign For Better Transport makes the dubious claim to have objectively measured the car-dependence rate of major British towns and cities, finding Nottingham least car-dependent, and Milton Keynes most car-dependent.

Lewisham, a borough seeking to cut its budget by 25% — £60m over 3 years — is having a laugh playing with fantasy Bakerloo Line extensions.

Billboard posters of woman in underwear will not cause car crashes.  That’s OK then.

Poor Brian Coleman, the Motorist’s friend in London, has had his taxi allowance cut.  What will he do next time he gets banned for speeding?

In a letter to Nature, biologists warn of plans to build a highway across the Serengeti: the road would cut the migration routes of large mammals like wildebeest, zebra and gazelle, and past experience says that this would be sufficient to cause a massive shift in the whole ecosystem of the park.  That’s The War Against The Motorist right there.

Finally, your moment of zen: 11foot8.com