So what was the 85%tile rule of setting speed limits?
Well basically we used to set speed limits scientifically and sensibly instead of on a totally arbitrary, Nimbyist, green political, subjective basis that we use now. In those days the strap line 'It's a limit for a reason' did have some merit. Now such claims are totally false.
Let me say I am able to say this because, unlike virtually everyone else in this green and pleasant land, I have surveyed, at my own time and expense, lots and lots of speed limit orders. Most I have surveyed have not been introduced for any other reason than at the request of some local Councillor to please a dozen local voters. I have not studied one single Speed Limit Order that includes an accident history to justify it, and none where accidents were caused specifically because the speed limit was too high.
Here's the proof.
We used to set limits on a scientific basis, the 85%tile Rule, which had served the country well for many many years. It's main advantage was that in no way was it subjective and open to political abuse, profit creation, and ideology. What we did was to measure the average speed that the majority of drivers, excluding the fastest 15%, were choosing for that section of road. This included the slowest and most pedestrian of drivers, excluded the fastest and the limit was set to the nearest round number, so that at 34 MPH the limit would be 30MPH and so on. And it worked very well.
Drivers' Union had this to say in a submission to the Enquiry on the Speed Limit Appraisal Tool in 2012:
'However the 85% tile rule that applied until the speed limit review of 2006, and still being implemented, was the nearest sensible formulae that could be applied in setting limits and was so applied for many years entirely successfully until its abandonment, for spurious economic reasons by a non-expert too.
Whilst the abandonment of the 85% tile rule saved local time and money, in road safety, the usual constraints on finance should never be applied or considered.
However, as previously discussed, the cost of arbitrary, unscientific speed limiting at £3,000,000,000 per 1 MPH and the social costs of drivers losing their jobs too don’t seem to have been considered.
Of course the 85%tile Rule wouldn't have allowed blanket speed limiting, as in 20 Zones, but 20 limits where drivers were showing they were appropriate and safe. Unfortunately the Green, Anti Driver, Anti Community Lobby, who do not see roads and streets as crucial infrastructure but more like play grounds, could not control our streets against a sensible formula so it has been abandoned.
The result is blanket limits where accidents were not happening, speed limits set for profit, major infrastructure slowed and hampered, and many thousands of perfectly safe drivers prosecuted for profit. They have been aided and abetted in this by no less than the Transport Research Laboratory, who claim to be independent but who we now have linked to Green anti driver groups. Read it here.
A classic example of an unscientifically set limit
See TrL bogus numbers for 20 Zones here.
I have just come across this article against the 85% tile system because it 'makes it harder to change speed limits' Read it here
Ok so without reading it, the strap-line says what it's about. The 85% tile stops ideology, anti driver green and profiteering policy from imposing bogus speed limits on us and they don't like it.
Here is some of it:
- 'because neither officials nor engineers really set speed limits. Drivers do.'
- 'the way we decide how fast people should drive is through something called the 85th Percentile Theory.'
- 'it assumes drivers are 1) reasonable and prudent, 2) want to avoid a crash and 3) want to get to their destination in the shortest possible time.'
- “Why don’t we design our roads for the speed we want people to go?'
- 85thBollichThese kinds of studies can stop a proposed speed limit change right in its tracks.' And so on.
My Petition says:
|'Reinstate the Eighty Five Percentile Rule for setting speed limits.|
We used to set speed limits scientifically and sensibly instead of on a totally arbitrary, Nimbyist, green political, subjective basis that we use now. In those days the strap line 'It's a limit for a reason' did have some merit. Now such claims are totally false.
The abandonment of a scientific method has resulted in blanket speed limit areas where accidents are not happening, speed limits set to please minority local interests, the over-slowing of crucial infrastructure, the prosecution of many perfectly safe drivers by virtue of arbitrary speed limits and a profitable Speeding Industry. '
An arbitrary Speed Limit Order: http://driveeastmidlands.blogspot.co.uk/2015/06/and-here-is-basis-of-high-earning.html
Drivers' Union Speed Limit Submission: http://bit.ly/23zqtCC
Sign the petition now to restore scientific speed limits here: https://petition.parliament.uk/petitions/129756
Still not sure? Read this for more info: