Sudden switch on - Motorway variable speed limit signs
Discussion
When the signs are switched on, some vehicles may be approaching just a few yards before the gantry.
The drivers might become aware that the red sign has suddenly illuminated above them, but too late to read the speed, or comply with the changed speed limit.
To obtain the maximum money, prosecutions might apply instantly, but that would not, if there was proof, be upheld by a court as being reasonable.
Is there a defined period, giving time for drivers to appropriately adjust their speed to the new lower limit?
Perhaps a one minute delay would be a sensible time allowed, before the initial prosecution.
Does anyone here know the official answer?
Jon39 said:
When the signs are switched on, some vehicles may be approaching just a few yards before the gantry.
The drivers might become aware that the red sign has suddenly illuminated above them, but too late to read the speed, or comply with the changed speed limit.
To obtain the maximum money, prosecutions might apply instantly, but that would not, if there was proof, be upheld by a court as being reasonable.
Is there a defined period, giving time for drivers to appropriately adjust their speed to the new lower limit?
Perhaps a one minute delay would be a sensible time allowed, before the initial prosecution.
Does anyone here know the official answer?
Thank you for all you replies.
The way things are these days, I was anticipating no delay time at all.
Expect you might have heard about the motorist, who forgot to tell the DVLA about their change of address.
Big mistake, which resulted in life changing consequences.
They made a second mistake, by not arranging any post redirect.
They made a third mistake, thinking that their car was ULEZ compliant. About one year away from complying.
You can probably guess the rest.
The ULEZ fine letters went to the old address. There were scores of them.
They now owe £26,000, but have never even dreamt of having that amount of money in their whole life.
Bankruptcy appears to be the only escape, with all the consequences that will involve.
Obviously the London Mayor has said pay up, or we send the boys round (or words to that effect).
Fore Left said:
lancslad58 said:
Most sensible drivers would have seen the queue ahead and already started to slow down.
There's not always a queue immediately ahead. They sometimes switch them on several gantries back.98elise said:
Agreed. The majority of variable speed limit signs I pass are well ahead of any slow traffic. Often there appears to be no reason for the limit at all and it reverts back to NSL after a few miles.
Very often that's the system working as intented, it'll slow traffic down over a wider area to prevent bunching and the sudden stop start associated with that. Meaning you might go 'slower' for a bit, but you'll keep moving overall faster than you would if left unchecked, and with less chance of a crash as people pile into stopped traffic at 70+Bedtime reading for those so inclined. https://www.gov.uk/government/publications/speedme...
"Speedmeter, traffic light and prohibited lane enforcement camera handbook
Item 4: Section 5.10.2 Variable speed limits
A. The speedmeter shall enforce the displayed speed limit when all the speed limit signs are mounted on the same gantry, facing in the same direction, over the same carriageway and all the speed limit indications are identical, not subject to the faults in section 9.11 and the speed limit has been displayed for one minute or longer. The one-minute enforcement delay shall be variable to at least five minutes. National Speed Limit may be enforced if any one of these conditions is not met".
[My bold].
"Speedmeter, traffic light and prohibited lane enforcement camera handbook
Item 4: Section 5.10.2 Variable speed limits
A. The speedmeter shall enforce the displayed speed limit when all the speed limit signs are mounted on the same gantry, facing in the same direction, over the same carriageway and all the speed limit indications are identical, not subject to the faults in section 9.11 and the speed limit has been displayed for one minute or longer. The one-minute enforcement delay shall be variable to at least five minutes. National Speed Limit may be enforced if any one of these conditions is not met".
[My bold].
lancslad58 said:
Most sensible drivers would have seen the queue ahead and already started to slow down.
But the sensible and also experienced drivers, who can see a clear motorway ahead, think about all the occasions when they have seen speed limit signs implementing lower speed limits, for no obvious reason whatsoever.
Correction - On those occasions, not meeting the speeding fines targets might presumably be a reason.
The very first lower limit sign, especially if switched on just as you approach the gantry, would normally be well in advance of a queue or obstruction, so sensible drivers (and the other type) would not usually be able to see the queue ahead, unless the particular stretch of motorway was straight for miles.
I have even seen on a four lane motorway, different variable speed limits displayed for individual lanes.
50mph -- National limit -- 30mph -- 60 mph.
I am sure that you only need one guess, to say what the drivers in lane 3 did.
A dangerous chaotic situation, caused entirely by the signs.
Again on that occasion, the motorway ahead was not obstructed at all.
Another reasonably common sight is seeing the sign 'End'. You then think, but there hasn't been a beginning.
I don't know whether it is still the same, but there has been an example of no end signs.
M25 clockwise J5 to J6. There are roadworks on that entire stretch of road, with a 50mph speed limit. After passing the J6 exit, a pair of derestricted signs should be displayed, but they are not present.
Imagine the confusion, as traffic entering the M25 West from J6 are aware that the 70 mph speed limit applies, but drivers already on the M25 Wetbound think the 50 mph limit is still applicable.
Jon39 said:
...I have even seen on a four lane motorway, different variable speed limits displayed for individual lanes.
50mph -- National limit -- 30mph -- 60 mph.
I am sure that you only need one guess, to say what the drivers in lane 3 did.
A dangerous chaotic situation, caused entirely by the signs.
Again on that occasion, the motorway ahead was not obstructed at all.
As indicated above, in that situation the cameras should not be actively enforcing the limit. 50mph -- National limit -- 30mph -- 60 mph.
I am sure that you only need one guess, to say what the drivers in lane 3 did.
A dangerous chaotic situation, caused entirely by the signs.
Again on that occasion, the motorway ahead was not obstructed at all.
Driver's do have some responsibility too. Knowing the Law and giving yourself a refresher from time to time isn't a bad idea.
In this case I'd contend that someone in lane 3 suddenly braking in response to a 30 Limit and causing a RTA might reasonably expect to be charged with Careless Driving.
M11rph said:
Jon39 said:
...I have even seen on a four lane motorway, different variable speed limits displayed for individual lanes.
50mph -- National limit -- 30mph -- 60 mph.
I am sure that you only need one guess, to say what the drivers in lane 3 did.
A dangerous chaotic situation, caused entirely by the signs.
Again on that occasion, the motorway ahead was not obstructed at all.
As indicated above, in that situation the cameras should not be actively enforcing the limit. 50mph -- National limit -- 30mph -- 60 mph.
I am sure that you only need one guess, to say what the drivers in lane 3 did.
A dangerous chaotic situation, caused entirely by the signs.
Again on that occasion, the motorway ahead was not obstructed at all.
Driver's do have some responsibility too. Knowing the Law and giving yourself a refresher from time to time isn't a bad idea.
In this case I'd contend that someone in lane 3 suddenly braking in response to a 30 Limit and causing a RTA might reasonably expect to be charged with Careless Driving.
And we're expected to think through all these things in a split second, on a high speed motorway surrounded by other traffic behaving unpredictably, as it always does?
Hmm.
Skodillac said:
Richard-390a0 said:
On a SAC this year I was told a minute grace period too.
Thirded, I was on a SAC a couple of weeks ago and was verbally told the same thing, 1 minute.Two posters mentioning SACs within a few hours !
We need to be careful, because anyone with several cars insured in their name, will eventually find a premium loading for all their cars for 5 years, not the 3 years that the points remain live. Insurers must make more money from speeding, that the fines raise.
I can tell you an SAC joke.
One gentleman (we had better call him driver A) attended one of those instructions sessions, where each driver was asked to rate their own driving ability.
Sensing that he had not been recognised by any of the others, driver A wrote, '7 out of 10, but not bad in 1979'.
Driver A was the Formula One World Champion that year.
Jon39 said:
Skodillac said:
Richard-390a0 said:
On a SAC this year I was told a minute grace period too.
Thirded, I was on a SAC a couple of weeks ago and was verbally told the same thing, 1 minute.Two posters mentioning SACs within a few hours !
We need to be careful, because anyone with several cars insured in their name, will eventually find a premium loading for all their cars for 5 years, not the 3 years that the points remain live. Insurers must make more money from speeding, that the fines raise.
I can tell you an SAC joke.
One gentleman (we had better call him driver A) attended one of those instructions sessions, where each driver was asked to rate their own driving ability.
Sensing that he had not been recognised by any of the others, driver A wrote, '7 out of 10, but not bad in 1979'.
Driver A was the Formula One World Champion that year.
Jon39 said:
To obtain the maximum money, prosecutions might apply instantly, but that would not, if there was proof, be upheld by a court as being reasonable.
As others have said, there is a grace period.
Fore Left said:
lancslad58 said:
Most sensible drivers would have seen the queue ahead and already started to slow down.
There's not always a queue immediately ahead. They sometimes switch them on several gantries back.Gassing Station | Roads | Top of Page | What's New | My Stuff