Safe Speed Forums

Prof - except for the psychological effect you noted - everything else is based on pure physics and probability.
It's taken me years to come to those conclusions, but the underlying maths is straightforward and sound - and verified by computer simulations.
I am currently preparing a paper for publication, so i don't want to give too much away. This is taking me a lot longer than I thought for various reasons, (not least of all being plain, old-fashioned procrastination) not because the principles are unsound but rather that I'm still a bit unsure of the direction I should be taking with it in order to have maximum impact.

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Only when ideology, prejudice and dogma are set aside does the truth emerge - Kepler

Sorry should have made myself clearer, and apologies in advance if I'm misunderstanding something or taking it out of context.

Going back to the original point that Pete317 picked up on in that a vehicle travelling a slower speed will stop in a shorter distance. I know that's not in dispute and I accept that in a single incident a vehicle can't be in the same place at the same time travelling at different speeds. The point I responded too was that if that if you took many examples of this it is just as likely that by travelling at a higher speed an accident could be avoided(since the car would be out of the area) as travelling at a lower speed the two would even themselves out.

My intial point was that if everything remained exactly as if there were no cameras such as concentration, frequency of speed checks, observation on the road and without a feeling of being under pressure then there is no reason why speed cameras wouldn't work. However this would only be in the small amount of accidents that are caused by someone being in excess of a posted speed limit.

That is why I support the aims of Safe Speed, as in a perfect world speed cameras could only hope to reduce a small propotion of accidents and that is dependent on all other factors remaining constant. I don't believe that everything does remain constant. I believe drivers devote to much attention to looking for speed cameras, checking on speed and this is being diverted away from observing the road. But who can blame them? Bad road safety policy has failed to take into account real world behavoir.

Oh and this is before you take into account the fact bad road safety policy doesn't tackle the motoring underclass and with the reduction in traffic cop numbers it is positively encouraging them.

As you will know from previous discussions I am broadly in agreement with your conclusions.

However, it's ultimately rather meaningless unless we can also factor in the answer to another big question: "What are the factors affecting 'speed' in critical situations?"

It's obvious to anyone studying the subject that the answer is that drivers choose speeds to suit the environment. This is the Safe Speed 'home ground' of course.

I don't know where I'm going with this, and I certainly don't intend to offer any discouragement, but I thought it worth mentioning...

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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

Yes. I'm attempting to quantify this, which is the one area in which my arguments are not yet robust enough for my liking - but I'm slowly getting there.

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Only when ideology, prejudice and dogma are set aside does the truth emerge - Kepler

happy new year to you all

not posted much recently, for reasons i am thankful to a poster for the pm i recieved.

anyway my view

fixed cameras - once you distinguish between a gatso, truevlo or specs (these are the only ones we use), once you see the box everyone slows down then accelerates away after (excluding spwcs ofcourse) so they will only slow the traffic down for that short length of time.

mobile units - the way i think is that if i visit site say at 9am on monday morning, then the vehicles passing, enter the area through the correct signage get flashed by other motorists and slow down, so if the motorist then travels the same road on tuesday at 9am / 11am / 2pm etc
they are that little bit more aware of their speed (i agree that the limit may not be suitable for that road but until the limit is changed then that is the limit)

i came into the SCP after the initial days and from personal experience looking at past figures have realised that at sites the speed of vehicles is to the limit (i judge this by comparing a history of nips issued)

however there are many requests to remove gatsos in favour of mobile enforcement as you never know when they are going to be there, in the same vein there are calls to have an open field where mobile units can enforce at whatever locations they want

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now retired