Safe Speed Forums

So we have recently 'learned' that 5% of crashes include exceeding the speed limit as a contributory factor. (Not that I haven't been telling you so for years! )

So how, exactly, are speed cameras supposed to reduce crashes by 40% to 60% at speed camera sites? I'd love to see camera partnerships trying to explain that one!

If 3% of the road network is covered by speed cameras (high estimate), then presumeably 3% * 5% of crashes are capable of being affected by cameras. That's 0.15%.

With 200,000 injury crashes per year, only 300 could be potentially affected by speed cameras.

With fatals, where 12% apparently include exceeding the speed limit we get 3,200 * 12% * 3% = 12 fatals could be potentially affected by speed cameras.

But of course...

- if speed cameras prevented speeding they would issue no fines.
- some of the crash involved drivers are 'rogue' drivers and won't be affected by cameras (yet they are a very risky group.)

So what are we left with? The benefit is the square root of bugger all and the side effects are everywhere.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Just playing devil's advocate for a second.

We know that the 2005 stats show that 5% of KSIs were caused by speed in excess of the limit. Have the number of fines issued fallen? Is it possible that drivers ARE travelling slower and as a result fewer accidents are happening above the limit?

OR is it that the muppets are taken in by the 'speed kills' matra leaving the more competent (and less likely to have an accident) drivers travelling at higher speeds?

Just a thought.

I'm off to bathe in caustic soda.

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Science won over religion when they started installing lightning rods on churches.

But then the NHS statistics would show a drop

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Wake me up when the revolution starts
STOP the Toll Tax http://www.traveltax.org.uk

Because drivers are avoiding speed camera roads totally and driving on other roads

traffic density is down at speed camera sites
therefore they are safer


is there any data on trafic volumes before and after cameras?

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Speed limit sign radio interview. TV Snap Unhappy
“It has never been the rule in this country – I hope it never will be - that suspected criminal offences must automatically be the subject of prosecution” He added that there should be a prosecution: “wherever it appears that the offence or the circumstances of its commission is or are of such a character that a prosecution in respect thereof is required in the public interest”
This approach has been endorsed by Attorney General ever since 1951. CPS Code

Yeah. Dr Linda Mountain found a traffic volume drop of about 10% associated with speed cameras. (from memory - I'll try and look it up later.)

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Not sure there's any mileage on this. The obvious answer from the SCPs is that dangerous speeding is concentrated on camera sites (because they've been so cleverly sited) so that the full benefit is felt there - on the small percentage of accidents caused by speed. Since there's no back-comparison data they'll probably claim that the no. of accidents caused by speeding used to be more, and those well-sited cameras are the reason it's down to 5% now.

Ian

That's the obvious comeback from them - but then how do they explain that hospital statistics show no drop at all?

The implication there would be that KSIs have increased for some other category, to the same level as the claimed drop due to speeding (probably distractions due to sudden braking at camera sites )

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Wake me up when the revolution starts
STOP the Toll Tax http://www.traveltax.org.uk

I need to get my thinking cap on.

Paul,

Do you have a figure for the total number of crashes per year regardless of whether injury/death is sustained?

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What makes you think I'm drunk officer, have I got a fat bird with me?

I don't think you can get to a definative answer but you can probably get close enough to show that the reductions can only be attributed to displacement and RTTM.

Thinking cap on, will report back!

Close enough will do for a figure at this moment in time

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What makes you think I'm drunk officer, have I got a fat bird with me?

We would need some data then.

How many camera sites and KSI figures for 2005 and 2004 for each one.

Then total KSI for uk 2005 & 2004.

Then we can start playing.

My query is completely unrelated to the mathematics that you want to play with....all I need at the moment is a 'near as damn it' figure for the total amount of crashes per year, regardless of how caused or any injury sustained.

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What makes you think I'm drunk officer, have I got a fat bird with me?

If you're thinking 'damage onlys' no one knows, and for two reasons...

1) It's hard to define a damage only... every little scratch? Car park scrapes?

2) Official figures don't cover damage only crashes.

But a fair guess is about 3 million damage onlys a year if we mean actual crashes.

200,000 recorded injury crashes a year.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

So too would the police's own data.

We've always known that we have a number of fateful, tragic co-incidences which all combine. Speed is not the cause as such - but the does affect outcome. As such - in some - but by no means all fatals - it's a contributory factor - distinguishable from the main cause. It's why COAST is used in DIS/SPeed Awares and why we are trying to get this code of practice out instead of deceiving that "all tragedy revolves solely around speed".

My ex-guv was hot and outspoken against cams and very much inclined to a COAST-led, safety-led enforcement. Humans will always make errors - and we will never achieve zero accident rates anywhere... but at least if we are COAST alert - we can avoid a good many of them.

As for the cam sites.. regression to the mean.. avoidance of the route.. even the use of the useful gadgets may all be part of the jigsaw here.

Our patch has only got one "cam" and no one knows where it is - a secret

But we did note that people just slowed for this cam and then accelerated again afterwards.

We did note that where they say our cars - complete with officers on the lurk - they tended to comply all the time.


We also noted that when we pulled people - they at least listened and I'd say majority pulled took note of the COAST lectures. We only prosecute if we have no other choices as education matters much more long term. Of course - any discretion depends on what we see and the margin of "speed above any tolerated limits". We throw the book at the careless and downright dangerous.. and show little mercy to these and drugged, drunk drivers. We do prosecute "fatigued" if we can prove this affected their competence too.

Of course - "discretion" can be a close call. Professional judgement is really on the line there.. but I'd say on the whole - we get it right.

When I trained many years ago - was told my professional judgement would always be questioned and I would have to live with this. I was also told to prosecute only if no other choice as educating a grateful member of the public had a more lasting effect than being seen as person who would and could arrest, fine .. punish just to "get the criminals caught stats". I was 22 when I joined as a graduate. I am now .. gulp.. - in early 50s

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Take with a chuckle or a grain of salt
Drive without COAST and it's all your own fault!

A SMILE is a curve that sets everything straight (P Diller).

A Smiley Per post
FINES USfor our COAST!

Approach love and cooking with reckless abandon - but driving with a smile and a COAST calm mind.

I think anyone with any common sense knows that fixed speed camera sites are a waste of time, and in my opinion are only sited to generate revenue.

How many times have you driven down a road and either been overtaken by michael Schumacker then a short distance in front of you on the approach to a camera you guessed it brake lights , or on dual carriageways its like a mexican wave speed up slow down etc etc.

I say to people cameras only make the road safe about 200 yards before and after a camera, and if they want to cross the road safely cross somewhere near a camera as you are less likely to get hit at speed than anywhere else away from one.

I do however think that certain people in government are slowly realising this and hopefully be reviewing the whole fixed camera situation, but until they find a replacement revenue generator then I think that they will stay a bit longer.

I have heard that they are going to trial mobile enforcement useing both PCSOs and traffic wardens, I know some forces do it but the PCSO will have the power to stop and issue a EFPT sometime in the future (god forbid).

As i said before it wont be long before Traffic / Road policing units will be a thing of the past I would say about 5 yrs if the government have there way.
Stephen

In Gear, my God, did you say 50's. Are you really that O L D.

SO AM I and doesn't experience show...

Stephen,

my only comment is... For God's sake, pedestrians should NOT cross anywhere near a speed camera because all the wally's are watching their speedos and NOT the road!

IMO that would be about the most dangerous place to cross the road - which is the main reason I am so anti strict enforcement of school zones. Speed limits for sure, but if they are STRICTLY enforced - 3kph tolerance here - drivers are watching their speedo rather than the road and the kids...

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Ross

Yes I'm a hoon, but only on the track!!!!

You suggest that people should cross the road near a camera where, in lot's of cases, they are placed on a downhill slope in a thirty mile an hour limit and the majority of drivers passing said camera will be spending way to much of their attention on looking down at that stupid needle!!!!

It's not that long ago that I used to say something similar to Stephen. That was before this.

When I started Safe Speed (2001) I had NO IDEA that cameras were actually dangerous - I thought they were pretty useless, misused and caused injustice. The results of the next couple of years' work worried me so much that I've been full time since 2003...

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

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Time to take responsibility for our actions.. and don't be afraid of speaking out!