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20 MPH zones

Posted: January 5th, 2020, 3:42 pm
by PrincessB
The signs used to be popular around schools and the idea seem to be spreading fast.

I've been through a few of them in the last few days and I didn't any real reason why you're supposed to drive so slowly down fairly urban roads.

Is the 20 limit enforceable? Would a speed camera in a 20MPH zone trigger if you went through at 30 or are the signs just some kind of guideline?

There's one on the road from Kempton Park to Hampton Court Palace. Admittedly, most of the time you'd be lucky to go faster than walking pace but on the rare occasion when traffic is flowing, I can see no reason to reduce speed so dramatically. That section of road has GATSO speed cameras midway through the restriction.

B.

Re: 20 MPH zones

Posted: January 5th, 2020, 3:49 pm
by swill453
Most of Edinburgh is 20mph other than the main arteries. It's definitely enforceable, but I think the word from the police is that enforcement "isn't a priority".

There's the occasional clampdown to get the message across, and yes you could get a ticket for doing 25 in a 20 zone.

I haven't heard of fixed speed cameras in a 20 zone, but I guess it's possible in theory.

(I'm assuming it's standard signage - black 20 on a white background in a red circle. The "twenty's plenty" signs are only advisory)

Scott.

Re: 20 MPH zones

Posted: January 5th, 2020, 4:09 pm
by bungeejumper
Absolutely enforceable. There's a section outside Bath, up near the university (so several miles out of town, and absolutely no schoolchildren), where the flying speed traps are coining it in. 25 mph and you're up for an NIP. Kerching! Unless you're a cyclist, of course, in which case you can take the hill at any speed you want. :evil:

Large parts of Bristol are now 20 mph, but it's not doing very much for pedestrian safety because it's actually become harder to cross the road. Previously, the cars travelling at 30 would bunch together a bit, so that there'd always be gaps between them where a pedestrian could make a timely crossing; but now, and endless series of evenly-spaced cars all doing 20 has made the gaps a thing of the past.

Bristol does have some pretty bad traffic problems, to be fair. But the first time I encountered a 20 limit was in suburban Manchester, on a main arterial road, where my satnav suddenly started bleeping about a speed limit that wasn't yet signposted. (Yes, sure enough, there was a primary school two streets away....) The young woman driving behind me was absolutely furious with me - tailgating, flashing, hooting - and when I finally turned off, she wellied it off into the distance with a screech of burning rubber. Another success for the road safety campaign.

Don't get me wrong, 20 mph zones are a fine idea where the young, the infirm and the elderly are around. But the sneaking suspicion remains that many of them are simple cash-cows with just a hint of virtue-signalling.

(I'm assuming it's standard signage - black 20 on a white background in a red circle. The "twenty's plenty" signs are only advisory)

Around our way, the twenty's plenty signs are run off privately and handed out by the local vigilantes. Who I also support - mostly......

BJ

Re: 20 MPH zones

Posted: January 5th, 2020, 4:32 pm
by bungeejumper
Snorvey wrote:It mentioned he was on a motorcycle, so one can only guess he'd gunned it in an attempt to impress his mates / school girlies.... or both.

I hope they put him back on a tricycle. For ten years, maybe twenty. Just saying.

BJ

Re: 20 MPH zones

Posted: January 5th, 2020, 4:42 pm
by jackdaww
i love the "twentys plenty" in scotland .

but this is no casual laughing matter .

some speed limits are not reasonable , but MOST are , and for good reason .

stick to the speed limits , and save yourself , and others injury , damage and a lot of inconvenience.

:x

Re: 20 MPH zones

Posted: January 5th, 2020, 4:44 pm
by tjh290633
Our narrow village high street has a 20 mph limit, which very few observe to the letter. It is complicated by having two pinch points, with priority for those heading out of the village at each end. The odd parked delivery vehicle often proves to be a more effective traffic calming measure, as does the once an hour bus.

Much of Brighton is 20 limit, apart from the main roads. It's not easy keeping your speed down as you descend a steep hill. It's also hard going up one, as you are probably accelerating over 20 before you change up from bottom gear.

In my view the principle is fine, but I feel that the US limits of 25 and 35, rigorously enforced, would be more effective.

TJH

Re: 20 MPH zones

Posted: January 5th, 2020, 4:46 pm
by JohnB
The big problem with 20 limits is their imposition seems arbitrary, they don't feel any different from 30 zones, and you don't see the signage in the visual clutter of a town. In Belgium where they are common you keep seeing end-20 signs and have no recollection where they started.. And for many roads they feel completely inappropriate, given the optical flow, you feel you are dawdling, and your mind wanders. I used to drive Hampton Court to Kempton Park every day, and that is a ludicrous road to apply 20s to.

School zone 20s are good idea if they apply when children are actually around, far too many are 24/7.

There is a convention in setting speed limits that they are only enforceable if 90% of the traffic keeps within 5mph of them, 20s break that, as almost no-one keeps to the limit having learnt to drive in 30 limit zones.

With compulsory speed limiters for new cars coming down the track, we could have a future of endless bimbling ahead.

Re: 20 MPH zones

Posted: January 5th, 2020, 5:34 pm
by jfgw
Snorvey wrote:I have said to the missus on more than one occasion that I suspect our local police asks the farmers in the area to head out in their tractors during peak hours.

Travelling at 30mph max for 6 miles behind a tractor on a road that is is impossible to overtake on is annoying....but remarkably safe!


Most farmers I get stuck behind pull in to allow other vehicles to pass when they can. Clearly, if there is no-where to pull in for a six-mile stretch, one would just have to be patient.

Rule 169:
Do not hold up a long queue of traffic, especially if you are driving a large or slow-moving vehicle. Check your mirrors frequently, and if necessary, pull in where it is safe and let traffic pass.


Julian F. G. W.

Re: 20 MPH zones

Posted: January 5th, 2020, 5:43 pm
by kempiejon
The WHO says
The relationship between speed and injury severity is particularly critical for vulnerable road users such as pedestrians and cyclists. For example, pedestrians have been shown to have a 90% chance of survival when struck by a car travelling at 30 km/h or below, but less than 50% chance of surviving an impact at 45 km/h. Pedestrians have almost no chance of surviving an impact at 80 km/hr.

https://www.who.int/violence_injury_prevention/publications/road_traffic/world_report/speed_en.pdf
30km/h = 18.6 miles/h
45km/h = 28 miles/h
Though I hear it's not speeding that causes most accidents. Exceeding the speed limit" was reported as a contributory factor in 5% of collisions and 14% of fatal collisions. https://webarchive.nationalarchives.gov.uk/20110504063239/http://www.dft.gov.uk/pgr/statistics/datatablespublications/accidents/casualtiesgbar/rrcgb2009
We have 5 mile/hour limits on work sites, hospitals, schools, car parks etc, yet my speedo doesn't have numbers below 10m/h.

Re: 20 MPH zones

Posted: January 5th, 2020, 5:56 pm
by bungeejumper
jfgw wrote:Most farmers I get stuck behind pull in to allow other vehicles to pass when they can. Clearly, if there is no-where to pull in for a six-mile stretch, one would just have to be patient.

Rule 169:
Do not hold up a long queue of traffic, especially if you are driving a large or slow-moving vehicle. Check your mirrors frequently, and if necessary, pull in where it is safe and let traffic pass.

You clearly have some very considerate farmers in your area. Around these parts, a tractorist who'll pull over to let you pass is about as common as a tractorist with a full and working set of rear lights - and with a proper number plate as well. Not a chance.

The general willingness to drive at a co-operative speed seems to vary in inverse proportion to the smelliness of whatever they're towing. Thus, a tank of slurry must be delicately transported if its nutritious top note of methane is to be adequately conserved for the moment when the farmer finally pops the cork. Whereas a few tonnes of hay can be thrown around with abandon, because if the odd bale falls off the wagon, the tractor driver will be over the hill and far away by the time the following driver has unbent his front wing sufficiently well to be able to give chase.

BJ

Re: 20 MPH zones

Posted: January 5th, 2020, 6:06 pm
by Lootman
jackdaww wrote:some speed limits are not reasonable , but MOST are , and for good reason .

The problem is that what constitutes a safe speed is highly dependent upon visibility, weather, road surface, amount of traffic, time of day and so on. So on a 20 mph stretch there will be times when 30 is perfectly safe and other times when 20 is too fast.

The ideal solution would be variable speed limits indicated by electronic signs, such as you see on motorways but not too many other places.

When in doubt I use my judgement about a safe speed rather than blindly follow a limit. And since I have never had a speeding ticket in 45 years of driving, I think that has proven to be a reasonable approach.

Re: 20 MPH zones

Posted: January 5th, 2020, 6:20 pm
by swill453
Lootman wrote:The problem is that what constitutes a safe speed is highly dependent upon visibility, weather, road surface, amount of traffic, time of day and so on. So on a 20 mph stretch there will be times when 30 is perfectly safe and other times when 20 is too fast.

The problem really is that the law has to cater for the lowest common denominator of driver, the ones who don't use good judgement and will always drive as fast as they can get away with.

If that means the rest of us have to sometimes driver slower than we otherwise safely could, then it's a price worth paying to keep vulnerable pedestrians alive. IMO.

Scott.

Re: 20 MPH zones

Posted: January 5th, 2020, 10:14 pm
by jackdaww
JohnB wrote:The big problem with 20 limits is their imposition seems arbitrary, they don't feel any different from 30 zones, and you don't see the signage in the visual clutter of a town. In Belgium where they are common you keep seeing end-20 signs and have no recollection where they started.. And for many roads they feel completely inappropriate, given the optical flow, you feel you are dawdling, and your mind wanders. I used to drive Hampton Court to Kempton Park every day, and that is a ludicrous road to apply 20s to.

School zone 20s are good idea if they apply when children are actually around, far too many are 24/7.

There is a convention in setting speed limits that they are only enforceable if 90% of the traffic keeps within 5mph of them, 20s break that, as almost no-one keeps to the limit having learnt to drive in 30 limit zones.

With compulsory speed limiters for new cars coming down the track, we could have a future of endless bimbling ahead.



========

would you prefer to walk and carry the luggage ?

8-)

Re: 20 MPH zones

Posted: January 6th, 2020, 6:03 pm
by sg31
swill453 wrote:
Lootman wrote:The problem is that what constitutes a safe speed is highly dependent upon visibility, weather, road surface, amount of traffic, time of day and so on. So on a 20 mph stretch there will be times when 30 is perfectly safe and other times when 20 is too fast.

The problem really is that the law has to cater for the lowest common denominator of driver, the ones who don't use good judgement and will always drive as fast as they can get away with.

If that means the rest of us have to sometimes driver slower than we otherwise safely could, then it's a price worth paying to keep vulnerable pedestrians alive. IMO.

Scott.


The lowest common denominator of driver won't obey the speed limit however high or low it is set.

Re: 20 MPH zones

Posted: January 7th, 2020, 9:41 am
by didds
sg31 wrote:

The lowest common denominator of driver won't obey the speed limit however high or low it is set.


id suggest such drivers are actually the lowest common denominator of humans.

Mistaken drivers appear higher up the ladder.

didds

Re: 20 MPH zones

Posted: January 7th, 2020, 10:01 am
by yorkshirelad1
PrincessB wrote:The signs used to be popular around schools and the idea seem to be spreading fast.

I've been through a few of them in the last few days and I didn't any real reason why you're supposed to drive so slowly down fairly urban roads.

Is the 20 limit enforceable? Would a speed camera in a 20MPH zone trigger if you went through at 30 or are the signs just some kind of guideline?

There's one on the road from Kempton Park to Hampton Court Palace. Admittedly, most of the time you'd be lucky to go faster than walking pace but on the rare occasion when traffic is flowing, I can see no reason to reduce speed so dramatically. That section of road has GATSO speed cameras midway through the restriction.

B.


I do understand 20mph signs outside schools. But not all the time: there's no point having a permanent 20mph sign outside a school during e.g. summer holidays. Most drivers tend to abide by signs when there's a sensible reason for them, but non-sensical signs seem to get less attention.

Re: 20 MPH zones

Posted: January 7th, 2020, 10:04 am
by swill453
yorkshirelad1 wrote:I do understand 20mph signs outside schools. But not all the time: there's no point having a permanent 20mph sign outside a school during e.g. summer holidays. Most drivers tend to abide by signs when there's a sensible reason for them, but non-sensical signs seem to get less attention.

We're moving towards having 20mph limits almost everywhere in towns. Is that nonsensical?

Scott.

Re: 20 MPH zones

Posted: January 7th, 2020, 10:15 am
by jackdaww
i suggest blanket speed limits -----------

towns 25

villages 25

duals 50

mway 80

ALL other 45 unless specifically signed.

8-)

Re: 20 MPH zones

Posted: January 7th, 2020, 10:29 am
by swill453
Might be the time to buy share in signage companies. In a city with mixed 20mph and 30mph streets, the 20mph streets need repeater signs at least every 200m on both sides...

Scott.

Re: 20 MPH zones

Posted: January 7th, 2020, 10:39 am
by tjh290633
yorkshirelad1 wrote:
PrincessB wrote:The signs used to be popular around schools and the idea seem to be spreading fast.

I've been through a few of them in the last few days and I didn't any real reason why you're supposed to drive so slowly down fairly urban roads.

Is the 20 limit enforceable? Would a speed camera in a 20MPH zone trigger if you went through at 30 or are the signs just some kind of guideline?

There's one on the road from Kempton Park to Hampton Court Palace. Admittedly, most of the time you'd be lucky to go faster than walking pace but on the rare occasion when traffic is flowing, I can see no reason to reduce speed so dramatically. That section of road has GATSO speed cameras midway through the restriction.

B.


I do understand 20mph signs outside schools. But not all the time: there's no point having a permanent 20mph sign outside a school during e.g. summer holidays. Most drivers tend to abide by signs when there's a sensible reason for them, but non-sensical signs seem to get less attention.

The school 20 limits around here only apply when the crossing patrol is there and the lights on the signs are flashing. The lollipop person switches the lights on or off, as required.

Why can't they do that everywhere?