Road rules9 mins ago
Average Speed Cameras On M6
Drove up the M6 on Monday night through the road works. Set the cruise control to 53 mph and was overtaken by loads of hgvs.
Does anyone know why these lorries can just charge through the road works ignoring the 50mph average speed check or am I missing something?
Does anyone know why these lorries can just charge through the road works ignoring the 50mph average speed check or am I missing something?
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Yes, enforcement of speed limits (by all methods) normally begins at (Limit + 10% + 2mph). This "allowance" stems from guidelines devised by the (now defunct) Association of Chief Police Officers (ACPO). They were introduced to reduce the number of frivolous challenges that were being launched on the basis of inaccurate measurements. The rationale being that it harder to argue that the measurement is 5mph adrift (for a 30mph limit) than it is to argue that is 1mph out.
The buffer zone still exists although challenging speed measurements is nor far harder than it was when the ACPO guidelines were introduced. Today a court dealing with a speeding charge is entitled to assume that an type-approved device operated in the correct manner is accurate. If the defendant wants to challenge that assumption it falls to him to show that the device cannot be relied upon - not an easy task even with expert advice and virtually impossible without.
The buffer zone still exists although challenging speed measurements is nor far harder than it was when the ACPO guidelines were introduced. Today a court dealing with a speeding charge is entitled to assume that an type-approved device operated in the correct manner is accurate. If the defendant wants to challenge that assumption it falls to him to show that the device cannot be relied upon - not an easy task even with expert advice and virtually impossible without.
To answer the presumption that the OP is speeding because his cruise control is set at 53mph - that’s a load of horse feathers.
My (not very old) Mazda had a speedo that was so inaccurate that an indicated 55mph was just under 50mph when properly measured - I know that for certain, because I used a GPS deviceto check it. So if I set my cruise to 53mph then I’d be well inside the limit - it may well be that the OP has checked his own car speedo in a similar way - and they ALL under read by a few per cent. Even my current bit of Vorsprung Dutch Technik reads 51.5mph for an accurate 50mph.
My (not very old) Mazda had a speedo that was so inaccurate that an indicated 55mph was just under 50mph when properly measured - I know that for certain, because I used a GPS deviceto check it. So if I set my cruise to 53mph then I’d be well inside the limit - it may well be that the OP has checked his own car speedo in a similar way - and they ALL under read by a few per cent. Even my current bit of Vorsprung Dutch Technik reads 51.5mph for an accurate 50mph.
"Ah, guilty until proven innocent eh."
Not at all, OG. It would be unreasonable to expect the prosecution to prove that a measurement device is accurate every time a speeding prosecution reaches court. Speed cameras and other equipment is "type approved" before use. Stringent tests are carried out on its accuracy. In the same way new cars are "type approved" to ensure they comply with the various construction & use regulations. Once type approval is granted the owner does not have to prove that things such as the lights, exhaust emissions, number plates and so on comply with those regulations if he is stopped.
Not at all, OG. It would be unreasonable to expect the prosecution to prove that a measurement device is accurate every time a speeding prosecution reaches court. Speed cameras and other equipment is "type approved" before use. Stringent tests are carried out on its accuracy. In the same way new cars are "type approved" to ensure they comply with the various construction & use regulations. Once type approval is granted the owner does not have to prove that things such as the lights, exhaust emissions, number plates and so on comply with those regulations if he is stopped.
"The guidance about not charging unless the speed is 10% plus 2mph above the limit is exactly that, guidance.
Police can enforce the limits and anyone driving outwith the limits can be fined or get points."
Indeed, and I did open my post with "Yes, enforcement of speed limits (by all methods) normally begins at (Limit + 10% + 2mph)."
However, apart from denton, above, I have only encountered one person who I know had enforcement action taken at below the guideline levels and he, shall we be polite and say "failed the attitude test" when he was stopped by a mobile patrol.
"...and thus it is reasonable to have to prove it's accuracy."
Its accuracy has been proved by its type approval, OG. Do you ask your electricity supplier to prove your electric meter's accuracy every time they send you your bill?
Police can enforce the limits and anyone driving outwith the limits can be fined or get points."
Indeed, and I did open my post with "Yes, enforcement of speed limits (by all methods) normally begins at (Limit + 10% + 2mph)."
However, apart from denton, above, I have only encountered one person who I know had enforcement action taken at below the guideline levels and he, shall we be polite and say "failed the attitude test" when he was stopped by a mobile patrol.
"...and thus it is reasonable to have to prove it's accuracy."
Its accuracy has been proved by its type approval, OG. Do you ask your electricity supplier to prove your electric meter's accuracy every time they send you your bill?
Years ago leeway was given in the Met as 10%. When our pursuit
vehicles stopped a motorist the police motorcycle or car had to be tested by a police garage hand within 24 hours on a rolling road in the Traffic Garage. Fleet No of vehicle and dates of testing and the offence were put in a log so,if contested, the police garage hand would trot along to court as a professional witness.Most older vehicles of the day had cable operated speedos from a gearbox attached to a hub on the drive wheels of the offenders vehicle.As accuracy of these speedos could not be ascertained the 10% rule was established. As tech progressed the electric pulse activated speedos were considered much more accurate and many forces,Thames Valley and Hants to name a couple take no prisoners if you are 1mph over. :-( The speedo on my skoda superb is accurate and shows the same speed reading on the cars fitted Sat Nav and also the Tom Tom I sometimes use
vehicles stopped a motorist the police motorcycle or car had to be tested by a police garage hand within 24 hours on a rolling road in the Traffic Garage. Fleet No of vehicle and dates of testing and the offence were put in a log so,if contested, the police garage hand would trot along to court as a professional witness.Most older vehicles of the day had cable operated speedos from a gearbox attached to a hub on the drive wheels of the offenders vehicle.As accuracy of these speedos could not be ascertained the 10% rule was established. As tech progressed the electric pulse activated speedos were considered much more accurate and many forces,Thames Valley and Hants to name a couple take no prisoners if you are 1mph over. :-( The speedo on my skoda superb is accurate and shows the same speed reading on the cars fitted Sat Nav and also the Tom Tom I sometimes use
NJ
"Do you ask your electricity supplier to prove your electric meter's accuracy every time they send you your bill?"
A couple of times my wife and I have been challenged in foreign airports by ground stewardesses at baggage check-in and asked for a hefty penalty for a kilo or two allegedly over.
When I have agreed that if my luggage allowance has been exceeded then we will pay the penalty providing they produce the latest calibration certificates for the scales. Suddenly "no speaka the English" is muttered and we get waved through. A racket.
"Do you ask your electricity supplier to prove your electric meter's accuracy every time they send you your bill?"
A couple of times my wife and I have been challenged in foreign airports by ground stewardesses at baggage check-in and asked for a hefty penalty for a kilo or two allegedly over.
When I have agreed that if my luggage allowance has been exceeded then we will pay the penalty providing they produce the latest calibration certificates for the scales. Suddenly "no speaka the English" is muttered and we get waved through. A racket.
