Safe Speed Forums

I first read this a long time ago, but didn't note it down and lost the info. I'm placing it here to make a quick record.

The West London Speed camera demonstration Project, published 1996:

http://www.dft.gov.uk/stellent/groups/d ... 23366.hcsp

The conclusions, on page:
http://www.dft.gov.uk/stellent/groups/d ... 66-02.hcsp

contains:
9. A highly significant increase relative to control data was found in accidents having Contributory Factor 216 'Driving too close to the vehicle in front'. Further detailed analysis showed that such accidents now form a higher proportion of all accidents in the study area, as has occurred to a lesser extent throughout the rest of London, and that they do not negate the overall benefit of the Demonstration Project.

The PDF of the whole thing is at:
http://www.dft.gov.uk/stellent/groups/d ... 023366.pdf

There's an anlysis of this report on the ABD website somewhere.

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

I can confirm this! I saw a white van parked at the side of the road up ahead, rear doors open, in a known Talivan area. Checked my speed - about 42 in a 40, braked to bring the speed down below 40 (looking at the speedo - must avoid 3 points and £60 fine (BIG mistake)). Unfortunately the car in front had stopped and was waiting to turn into a pub. I had left plenty of room but the road was wet and I slide gracefully into the back of it. Impact at about 20 mph. £2000 worth of damage to my car I consoled myself with the thought that it wasn't a pedestrian crossing the road. As I passed the van it turned out it wasn't a talivan after all, just a delivery van

With my concentration elsewhere I had not observed the car ahead had stopped.

Funnily enough my 20 year incident free driving record came to an end last Friday. About 30m past a static camera I pulled up because the traffic in front had stopped due to someone turning right. "Tracy" behind me was probably doing a similar check as she passed the camera. I heard the dread skid of rubber on wet tarmac with just enough time to jam my foot on the brake but not enough to get my head back into the headrest. Not to worry the impact soon did that.
This took place in a 30 zone, in a village, at 4pm, how easy it would have been to exchange my car for a kid with their head in a bag of sweets!

This thread appears to me to be about the most important one I have read. I have long felt that this would be the case but have never been able to find a study to back it up.

We now have 40kph zones around schools, usually accompanied by specific times that they apply (8.00am-9.30am and 2.30pm-4pm weekdays) so first you see the sign, then you check your watch, then you look at your speedo until you get down to the desired speed, and then you hit the child you did not see because your attention was elsewhere.

Simplistic, but I honestly believe that once these limits have been in place long enough to do realistic statistics we will see an increase in children being hit outside schools.

The focus needs to be on the road ahead at ALL (except for occassional checks of the mirrors) times. The more we are forced to watch our speedo the more accidents will happen, particularly at low speeds around towns where it is sooooo easy to creep up a few mph. So we watch the speedo and have more rear-end and pedestrian collisions....

_________________
Ross

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

I don't know if anybody can confirm this with data but I have definetly noticed people speeding up to a higher speed right after a camera than they otherwise would have been doing had the camera not been there but then going back to the cruising speed they were doing b4 camera, so it goes:

(1) Cruising 35MPH

(2) Camera zone 30-35MPH

(3) Right after camera zone 35MPH+

(4) Significantly past camera zone, back to 35MPH

Why are they accelerating up to this speed then coming back down. I think drivers are over-estimating how much they slowed down by from their cruising speed so accelerating more than they need to to get back to their cruising speed. This is proof that normal law abiding motorists are going at a speed governed by their surroundings and experience rather than an insignificant value.

As well as this we have cars going slower than they would have been say up to 500M before the camera then faster than they would have been 500M or so after the camera, this however would cancel out any speed reduction and the overall average speed doesn't change.

Andrew

_________________
It's a scam........or possibly a scamola


Homer Simpson

There is a strong research basis for this common sense point of view. There is a great deal of evidence to suggest hazard detection is impaired when your attention is split between speedo and the outside world. If you can argue a robust link between the existence of speed cameras and increased in-car attention (checking your speedo) then there is a pretty sound scientific basis for saying that speed cameras are not safe.

Exactly, Sam. Have a look at http://www.safespeed.org.uk/speedo

M60 today ....


Had to go down to Wythenshawe to see a patient I had referred to their heart unit there....

Drove at slow crawl through the road works around Altrincham Spur J7/J6.

Passed lollipop proclaiming that 40 mph tempo was three quarters of mile off and the speed cam was less than a yard behind this lollipop and obscured by the sign. There was ... a rear end shunt in L2.... Whether this had anything to do with the scamera is for us to possibly think that and the authorities not to be able to possibly comment ...

Further along there was a near miss - again in vicinity of scam number two -- the woman in a Vectra decided to change lane and a silver Merc was in her blind spot accelerating in L1 . This was just past the Sale slip road entry to M60.... She had stayed in L2 until past the exit and then decided to move back to L1 once she had allowed traffic onto m/way...but in fairness ... the Merc was accelerating to 40 mph and she was hovering below 30 mph I was behind her. I think she had seen scam and slowed down to below 30 mph... She had slowed and kept relatively steady at 35 mph from entering the roadworks...but for some reason slowed even more at Gatso number two here.

All credit to the lady - she saw the Merc in time and aborted the manoeuvre - waving an apology. And credit to the Merc driver -- he eased off and allowed her entry to L1 as well. So nice to see "mistakes" corrected quickly and no aggression displayed by either driver. I think and hope both drivers will learn from this experience as well.

However, I get the feel that the scamera took the concentration away from both drivers - judging by the deceleration. I could swear the lady was looking at her speedo and not her rear mirror..... Everything else about her driving suggested competence as I had followed her down the M60 from M6/M61/M60 and then to A5103 and she continued along M56...

The Merc also followed to M56 and again - general feel about his driving style such as I observed was competent.

Then the last scam.... you see the NSL road works clear and this thing was flashing away as motorists started to accelerate twoards it just before J5 to M56/A5103 and Wythenshawe....

Whilst I see the need to enforce low speed limit in road works as slow tootle through is common sense really .... this was overkill

Made much worse by the obvious MONEY GRABBING siting of two of these scams.

It was the same on the return. J5 ... scam just after 40 mph sign proclaiming compulsory tempo three quarters of mile off.

Consultation with A&E Wythenshawe revealed lot in incoming whiplash wounded from this area... more so since rtoadworks appeared and even more so since scams appeared to enforce.

I gather that these are also set at a very low tolerance..... from those working in this particular hospital.

As a way of giving the camera "the finger"? "I slowed where you could see me so as not to get a ticket, but now that I’m out of your zone, pah, have this brief speed fart."

Some drivers I know play the following game: If it's a 30 camera, they'll enter the grid at just above thirty, then FLOOR it, the idea being to collect enough speed so as to trigger the camera right at the end of the grid.

The theory is that the first flash will catch them on the grid but by the second flash they'll be clear. No prosecution will be possible, two exposures will have been wasted, and contempt unambiguously expressed.

Although the theory works on spreadsheet calculations, so far no one I know has managed to trigger a "safety camera" in this way despite quite a lot of trying.

When it's quiet, speed camera grids can be useful for checking stopping distances.

If the scam is where the 40 mph zone is still 3/4 mile away then the 40 limit can't apply can it? You can only put a scam set to 40 ish within the actual restriction for roadworks. Or are you saying there is a sign setting out the 40 limit 3/4 mile away from where the roadworks actually start? I also had a feeling that a speed trap before the first repeater after a limit change was a no-no and broke either the netting off rules or the ACPO guidelines. I may be deluded though

I don't think they're going to get anywhere. I'm sure I read somewhere that it checks speed twice. If it detects a big difference between the first and the second reading the it assumes something is wrong and does not take a photograph. I don't know how far apart the readings are taken so I can't be certain that heavy braking or harsh acceleration would cause the readings to be sufficiently different.

Also, it makes sense for the camera to detect speed on the way into the trap rather than on the way out, otherwise what you describe would be more common. If so, entering the trap at a speed lower than it's set for will mean no flash at all, and if just over the threshold you'll get a ticket. There's probably no road car on the planet that would be able to accelerate out of the trap in the half second or so before the next flash.

Third point, even if you could get beyond the markings by the time the second picture is taken you may well still be in the frame of the photo. If that happens they still be able to work out speed from other things such as position of street furniture, spacing of lane markings or central white lines or shadows from trees or buildings.

Even if the car doesn't appear in the second photo at all they would still be able to issue a fine. Look at it this way, say the trap is 30 yards long and both photographs cover, say 50 yards of road. The first photo shows a car 20 yards in with 10 yards of trap left to go, but 30 until it's actually out of shot. If the next photo shows nothing at all they will know that the car covered at least 30 yards in about half a second. So they won't be able to work out an exact speed, but they will be able to work out a minimum speed. Bugger, 30 yards in half a second is 123mph and they have the registration from the first photo. So in the unlikely event you could get in only one photograph there's still little or nothing to stop the NIP going out.

_________________
Make everything as simple as possible, but not simpler - Einstein

The Gatsos I was thinking of are one-camera set-ups with two grids – one grid on each carriageway of a two-way road, with the camera looking in the same direction as a driver on its side of the road.

Reading the twin-grid set-up naively, it looked as if the camera would react to anything big enough in its range that was travelling faster than its trigger speed. Since the two grids were level, it looked as if the radar range would have extended to the grid lines farthest away from the camera.

If you entered at 32, and accelerated suitably you’d exceed the trigger speed (40?) just beyond the second last gradation, and would be clear of the grid by the second flash. However, you would also have been clear of the grid had you been doing 30. Making an estimate of speed from street furniture would be possible, but might be difficult to rely on in court.

That was the theory.

The evidence so far supports your theory. The camera doesn’t seem to read things at the far end of the grid – so despite what the road markings imply, it isn’t a two way Gatso.

_________________
Speed doesn’t kill. This thing we’re all on is going at 66,000 miles an hour. Not everyone gets a smooth ride, but that’s another question.

Presumably this scamera was set to 70, since the 40 limit was still 3/4 mile away?

Still, rather an odd place to put it, they normally put the scameras inside the 40 mph zone itself.

Well, I'm only guessing about how they do it, but there must be an approved method that's acceptable to a court (in the unlikely event the driver doesn't accept the FPN). Not all Gatsos have the markings. Most sure, but not all. I expect those trailer mounted temporary Gatsos that they like to use in roadworks often don't have any markings.

Almost certainly not. Someone else here (can't remember who, sorry) explained that the markings on the other side of the road are there in case someone speeding overtakes in the trap area, not for oncoming traffic. I'm not sure there's any such thing as a two way Gatso.

_________________
Make everything as simple as possible, but not simpler - Einstein

Road works are the only place, where i believe cameras are required.

I have seen too many prats hurtling through road works above the speed limit. This is an area where workers are in the road. Cameras are the only way to stop the prats flying through them and injuring or killing road workers.

_________________
Steve

Just see if you can find any supporting data! I've tried, believe me. It seems to all stem from some very crap research in Texas about 15 years ago.

The DfT quoted 5 workers killed in roadworks in 2002, but guess what, they weren't killed by cars (let alone speeding cars), they were killed in the process of their work.

I suspect it's just another pack of lies.

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

Perhaps not speeding through road works doesn't have to boil down to killing people.
Perhaps its just a simple case of having a modecom of respect for the individuals working a few feet away from traffic, and suffering the continuous noise and buffeting from vehicles. You may just help to improve the quality of their working environment.
And yes, I am fully aware that roadworks aren't always being worked.

I wasn't trying to "take a position" on the subject - at least not beyond: "show me the data". Let's see some real data, then make judgements based on safety shall we?

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

It does if that's the way roadwork cameras are being justified.




I quite agree, and I'll always be doing no more than the temporary limit through any stretch of active roadworks, even if the only workers you see are the ones bunched together on the other side of the other carriageway having a teabreak, or huddled around watching one of their mates digging a hole... not that the dedicated, hardworking gentlemen currently occupied with the southern stretch of the M11, who I passed several times earlier in the month on the way back and forth to Stansted, would behave in this manner, heaven forbid

But if that is the genuine reason for wanting to reduce speeds through roadworks, then why the pluck don't the government simply tell us this, instead of trying to, yet again, paint the motorist as an evil murdering scumbag who needs to be forced into slowing down before they kill a poor defenceless roadworker. Treat motorists with respect, explain the real reasons behind the speed restrictions (maybe even spend a bit of cash on some adverts showing us what it feels like to be stood a couple of feet away from thundering motorway traffic at NSL+ speeds), and I suspect there'd be less cynicism from the average motorist who currently just sees roadwork cameras as money-grabbing machines...




Mmm, yet the restrictions are still there. So, regardless of whether the lower limits are to prevent roadworker fatalities or simply to give them a better quality of life in their working environment, if there aren't any roadworkers on site, then the limit should be raised. OK, in many cases the modifications to the road layout (narrowed lanes, contraflows etc.) would make it unsafe to simply switch off the temporary limit, but why couldn't we at least see a 10-20mph increase (e.g. treat a contraflow section like a NSL single carriageway, or a narrow lane section like a comparable stretch of dual carriageway)?

Again, it goes back to treating the motorist with respect, something the government and its agencies seems particularly incapable of doing. Or, more cynically, something they could be quite capable of doing, if they actually wanted to...

Contacted the local scamerati down there when I got back home the other night - asking about this particular scam. Drove past it today ... it now has a white bag over it and sign saying it is "not in use!"

However, doubt any scammers made any money today ... took me hours to get back home tonight