[tomtom]

that in some locations, during rush hour, cyclists not only outnumber private cars but
all other road vehicles (private cars , lorries, taxis motorbikes buses) to constitute 64% if vehicles.

Not commenting on the rest of what you said - but the above introduces another interesting concept whereby as the amount of cyclists increase you reach a tipping point where it gets safer as there are so many cyclists they start to outnumber cars - and by being the dominant form of transport car drivers are forced to take more notice of them - and thus cyclist accident/death rates fall at a higher rate.. theres a name for it (sorry forgotten - but its named after the person who came up with the idea - its Sydneys law or something like that..)

[SA Chris]

Cole's law

(edit - included smiley as it's a joke, sorry)

[tomtom]

Cole's law

Thanks - memory lik......

[i.munro]

that in some locations, during rush hour, cyclists not only outnumber private cars but
all other road vehicles (private cars , lorries, taxis motorbikes buses) to constitute 64% if vehicles.

 - and thus cyclist accident/death rates fall at a higher rate.. theres a name for it

it's called "the presence of witnesses"

[slackline]

IIRC, the whole 'helmets makes you worse off' debate is based on one Australian study (where its compulsory) where they measured how close people drive to cyclists with and without helmets. They showed (nto sure how well) that motorists drove closer to those with helmets - to which the paper 'interpreted' this to mean that motorists assumed those wearing helmets were protected to a degree so they could drive closer to them.

I know of no other study that supports these (oft cited) findings - but am happy to be corrected otherwise..

See the last link I posted which is data from the UK from a guy who commutes in Bath and recorded just such data.  Someone in the US attempted to replicate it (also linked in my post below).

When considering whether helmets reduce the overall risk of dying (or being seriously injured) from cranial trauma* then in light of the evidence which suggests cars pass closer when cyclists are wearing a helmet (or appear to be male) it becomes more complicated because you have two factors in play...

1) The probability of being hit in the first place.
2) The probability of dying/sustaining serious injury from cranial trauma.

Wearing a helmet increases the probability of 1) happening but wearing a helmet decreases 2) (conditional on the helmet actually being worn properly**).  Whether the decrease in the later is sufficient to offset the former I've no idea and, and from a crude literature search, there aren't any studies/reports on it.

* They're of no use if you're run over by an HGV which crushes you, or hit at high speed and tossed around like a rag doll.
** I'd contest from cycling around for a number of years that many aren't worn properly, particularly in winter when people squeeze them on over wooly hats.

Not commenting on the rest of what you said - but the above introduces another interesting concept whereby as the amount of cyclists increase you reach a tipping point where it gets safer as there are so many cyclists they start to outnumber cars - and by being the dominant form of transport car drivers are forced to take more notice of them - and thus cyclist accident/death rates fall at a higher rate.. theres a name for it (sorry forgotten - but its named after the person who came up with the idea - its Sydneys law or something like that..)

Holland is a good example of this taken to the extreme.  Cycling is so popular that in many places (not in Amsterdam though where space is limited) they build 3m wide paths parallel to roads to segregate cars and cyclists from each other.  Plenty of blog posts and scholarly articles out there for those interested.

[petejh]

These figures for the whole of London from the DfT 2012 report are quite eye-opening to me:
Number killed or seriously injured by vehicle type:
Pedestrians 5,272   Cyclists 4,619   Motorcyclists 4,653   Cars 12,298

Taking those figures and combining it with what I saw in central London yesterday:
There are obviously hundreds (thousands?) times more pedestrians than there are cyclists in London.
There are hundreds times more cars than cyclists.

The figures quoted here
 http://www.standard.co.uk/news/london/move-over-amsterdam-the-london-cycling-revolution-is-in-top-gear-8671069.html

would suggest that your impressions are simply wrong & that in some locations, during rush hour, cyclists not only outnumber private cars but
all other road vehicles (private cars , lorries, taxis motorbikes buses) to constitute 64% if vehicles.

It doesn't suggest my impressions were wrong at all, in fact if you dig into the London Evening Standard report and compare it with the Department for Transport accident statistics it reinforces what I'm saying about the relative risk of cycling/cars in Central London.

If you read the LES report down to mid-way, it gives an overall figure for road use in Central London: 'Bikes now account for 24 per cent of all road traffic in central London during the morning peak and 16 per cent across the whole day.'

Accidents don't just happen during the two rush hours.

(https://www.gov.uk/government/publications/reported-road-casualties-great-britain-annual-report-2012) The accident statistics for the 8 Central London boroughs (City, Camden, Chelsea/Kensignton, Islington, Tower Hamlets, Lambeth, Southwark, Westminster) show that there were a total of 8112 serious injuries or deaths between two groupings of road user:
Group 1: cars, vans and light goods vehicles combined,
Group 2: cyclists.
There were 2068 cars/vans/light goods users killed or seriously injured in the 8 central London boroughs - which equals 25% of total injuries/deaths of all road users in those boroughs.
There were 2128 cyclists killed or seriously injured, that equals 26.2% of total injuries/deaths of all road users.

So cyclists make up 16% of total road users in Central London throughout the day according to the most recent and most comprehensive census, yet cyclists make up 26% of serious injuries or deaths in 8 Central London boroughs.

I'm not pro or anti cyclist btw, and there does seem to me to be a lot of in-group biases going on in any discussions about cycling safety. I'm just pointing out what should be obvious to anyone who takes the time to look at the injury statistics in the DfT report. The injury statistics for central London boroughs make for sobering reading and should inform your opinion about the risk of cycling in those locales.
For me personally the figures would make me seriously consider whether the risk of cycling in those locations was worth it. That's all. I'm not interested in hearing biased opinions from any group either pro or anti cycling, the statistics, a pair of eyes and a brain tell you all you need to form a balanced opinion about the relative risk. Hopefully numbers of bikes will continue to increase in all UK cities until they are the dominant vehicle, Coles Law is in full effect and they are the most obvious and safe choice. But that's clearly not where we're at right now.

[i.munro]

16% of the traffic is not consistent with  "There are hundreds times more cars than cyclists."
At the very most it means that there are 6.25 times as many & that assumes that there are no taxis lorries or buses.

[petejh]

16% of the traffic is not consistent with  "There are hundreds times more cars than cyclists."
At the very most it means that there are 6.25 times as many & that assumes that there are no taxis lorries or buses.

For the sake of brevity I typed 'cars' to mean all motorised vehicles, it was a throwaway term. But not 'hundreds', no. The interesting part of my post is the accident ratio no?

[Zods Beard]

Jesus wept, wish I hadn't asked as I'll be dead by Christmas.

[petejh]

 


Least you won't die ignorant.

[i.munro]

 But not 'hundreds', no. The interesting part of my post is the accident ratio no?

Not hundreds, or  tens , or ten or even  five. Perhaps you have the figures for the % of vehicles in  the car/van group,I don't?
Perhaps twice as  many cars  ??

Given that, surprising thing about your accident figures , for me, is that car travel doesn't actually appear to be that much safer than cycling despite all the money spent on it , the viciously anti-bike mayor  & everything else.

[ianv]

Jesus wept, wish I hadn't asked as I'll be dead by Christmas.

It has to be said, the run up to Christmas is the most "exciting" period for commuting. Probably all the office parties

[fatdoc]

what ianv said... and agree with bubba on filtering ++

and.. though im not a fan... high Viz wear of some sort is now the norm... so get some..

keep safe.

[petejh]

...
Given that, surprising thing about your accident figures , for me, is that car travel doesn't actually appear to be that much safer than cycling despite all the money spent on it , the viciously anti-bike mayor  & everything else.

It needs someone better equipped than me to work out the relative risks but the answer will be in what percentage of road users are in the car/van/lightgoods group. If bikes account for 16% road traffic overall throughout the day then all the different motor vehicles must account for the remaining 84%. Take away buses and large trucks and you have the figure. Lets say, for sake of argument, the remaining 50% are cars and vans etc.

So,
25% of people killed or seriously injured in road accidents in C.London come from a group (cars/vans etc.) comprising 50% of total road users.
26% of people killed or seriously injured in road accidents in C.London come from a group (cyclists) comprising 16% of total road users.

That looks to me like you're approx 3 times more likely to end up seriously injured or killed in a road accident if you cycle in central London every day than if you drive a car or van, but someone better than me with my D-grade maths would need to look at it to do it properly. Of course it doesn't mean that much if the likelihood of injury/death (for car drivers etc.) is so extremely tiny as to be not worth worrying about in the first place...

[slackline]

Micromorts are useful, a concept introduced by David Spiegelhalter (who's in the video I linked quite a bit below).  These are of course averages and don't account for geographical variation.



http://en.wikipedia.org/wiki/Micromort

[i.munro]

 Take away buses and large trucks and you have the figure. Lets say, for sake of argument, the remaining 50% are cars and vans etc.

So,
25% of people killed or seriously injured in road accidents in C.London come from a group (cars/vans etc.) comprising 50% of total road users.
26% of people killed or seriously injured in road accidents in C.London come from a group (cyclists) comprising 16% of total road users.

There are all sorts of reasons for believing that that 16% figure is an underestimate of the number of cyclists but I'd guess we're in the right sort of ballpark now i.e. 3 times as many cars as cycles on the road overall.
Importantly , during busy periods, when road space is at a premium,  this is much lower.
If we take your guesstimate that 36% of traffic is buses lorries & taxis & 24% is cycles then it's less than twice as many.

It's easy to assume that transport in London is car dominated because they are allocated all the space, priority & money but in practice the numbers are (relatively) extremely low.

Sorry to bore everyone crapless with this but the technique that you (I assume inadvertently) used, of associating genuine stats with a whopping great lie, is one that the tories & the right-wing press use frequently to peddle their shit & it really winds me up.

[petejh]

Ummm... What? 
I'm not coming at this from any political angle?! - I don't have the faintest idea of what the various parties views are about cycling, either nationally or in London. The accident figures are what they are and these, when related to the approximate numbers of different vehicle types is what I find interesting because it's how you can cut through any bullshit and see what are the true relative risks.
The figures suggest two groups (cars/vans/lightgoods, and cyclists) with the same overall number of road accidents yet one group outnumbers the other by approx 3:1. Therefore that suggests an accident is 3 times more likely for people in the smaller group. There's nothing political about that.

You seem to agree with the figures, but then again maybe you don't because then you suggest it's all a political big fat lie by someone or other - 'tories' - with a grudge against cyclists. Talk about none so blind as those who won't see.

I don't understand how you relate this sentence:

There are all sorts of reasons for believing that that 16% figure is an underestimate of the number of cyclists but I'd guess we're in the right sort of ballpark now i.e. 3 times as many cars as cycles on the road overall.

to this one:

It's easy to assume that transport in London is car dominated because they are allocated all the space, priority & money but in practice the numbers are (relatively) extremely low.

Sorry to bore everyone crapless with this but the technique that you (I assume inadvertently) used, of associating genuine stats with a whopping great lie, is one that the tories & the right-wing press use frequently to peddle their shit & it really winds me up.

edit: I've just read the reader comments on that LES news report - fuck me I see why you're so defensive now, didn't realise I was talking about religion here!

I too apologise for boring everyone crapless.

[i.munro]

But you have shifted from your original assertion that there are "hundreds of times more cars than cycles" (which would lead to the conclusion that cycling is 100s of times more dangerous) to the  position that there are around 3 times as many.

TFL & the mayor have a vested interest in people beleiving  that this ratio is much higher than it actually is in order to justify the way that they choose to allocate resources

[Snoops]

http://www.independent.co.uk/news/uk/home-news/boris-johnson-ban-cyclists-from-wearing-headphones-8948964.html

I think a ban is ridiculous idea, but he is right how crazy it is to wear headphones whilst cycling on roads. There seems quite a few commuting in Sheffield with the music on, and I do think 'death wish'

Surely passing compulsory bike helmet law (like in Oz) would be more useful in reducing deaths?

Depends whether you consider the proximity with which cyclists are passed by cars is a factor.  If so you could just grow your hair long and look like a girl....

http://www.drianwalker.com/overtaking/

Usual caveats of sample size, reading the paper yourself and drawing your own conclusions apply, and of course there may be spatial differences due to the factors that petejh highlighted which are discussed in this blog post.

http://bamboobadger.blogspot.co.uk/2009/03/bicycle-overtaking-and-rebuttals.html

Re the helmets, we've been here before. Here's what I said/think. I've seen a few more since then as well:

Quote from: Duma on August 02, 2012, 07:22:24 pm

 (really think having a lid on will make the slightest difference when a juggernaut turns left onto you?),

Yes. It will increase your chance of not having a permanent head injury if you pull through. Several times a year I have the pleasure of seeing cyclists in Sheffield in the Royal Hallamshire. There are exceptions, but most of the ones with brain contusions and questionable neurological prognoses weren't wearing a helmet

I'm sure you can find a few links telling me I'm wrong Slackers!

[Snoops]

I wear headphones cycling (but not at max volume).  I'm certainly not about to look over my shoulder just because a vehicle is approaching.  I'll look behind me before signalling to manoeuvre and not wearing headphones would not change this one bit.

Should deaf or hearing impaired people not be allowed to cycle because they can't hear whats going on around them? (which is presumably the logic behind proposing a ban on headphones).

Of course not, but then they don't have a choice do they........
If you want to make bizarre comparisons, why don't you cycle to work on a hand cycle bike? My mate whose missing his legs would much prefer to have a normal bike given the choice.
(Ps I said in my original post a ban was ridiculous), I still think your crazy, still its a free country and neuro care is free!

[SA Chris]

Jesus wept, wish I hadn't asked as I'll be dead by Christmas.

Maybe rethink your attire needs..

[petejh]

But you have shifted from your original assertion that there are "hundreds of times more cars than cycles" (which would lead to the conclusion that cycling is 100s of times more dangerous) to the  position that there are around 3 times as many.

TFL & the mayor have a vested interest in people beleiving  that this ratio is much higher than it actually is in order to justify the way that they choose to allocate resources

I know, and I already said I was wrong, my 'hundreds' comment was a throwaway without looking at any figures, which you've got hung up on -  even though I've since looked at the figures and said the actual ratio is more like 3:1.

I have no vested interest, other than simple curiosity to find out some facts.

[slackline]

Re the helmets, we've been here before. Here's what I said/think. I've seen a few more since then as well:

Quote from: Duma on August 02, 2012, 07:22:24 pm

 (really think having a lid on will make the slightest difference when a juggernaut turns left onto you?),

Yes. It will increase your chance of not having a permanent head injury if you pull through. Several times a year I have the pleasure of seeing cyclists in Sheffield in the Royal Hallamshire. There are exceptions, but most of the ones with brain contusions and questionable neurological prognoses weren't wearing a helmet

I'm sure you can find a few links telling me I'm wrong Slackers!

No need, read the other posts I've made and you'll see that I agree with you on this. 

[SA Chris]

http://dutchbikeguy.wordpress.com/2013/11/18/ultra-shocking-video-about-lorry-blind-spots/

Interesting vid (sorry if posted already!)

[ianv]

Maybe rethink your attire needs..

I never let my lad out of the house unless he is suitably attired. Just need to spray him in dayglow yellow for total peace of mind.


002 by ianvincent, on Flickr

Off to the shops!