60 mph sign on single carriageway road in the UK

[the cheesecake man]

I wonder what the biggest roundabout in the country is, in terms of area that is enclosed by the circulatory carriageway (noting that gyratories don't count...)

Bignell's Corner is pretty big - I wonder if there's anything bigger...

It looks to me like Coryton (M4/A470) is about 1.5 times the size of Bignells Corner.

I believe that under the SABRE constitution it's compulsory to mention Skelmersdale at this point.

[Chris5156]

I wonder what the biggest roundabout in the country is, in terms of area that is enclosed by the circulatory carriageway (noting that gyratories don't count...)

Bignell's Corner is pretty big - I wonder if there's anything bigger...

It looks to me like Coryton (M4/A470) is about 1.5 times the size of Bignells Corner.

At the risk of taking us off topic - is Coryton still a roundabout? It’s now got a weird cut-through to the A470.

[dereer]

There are plenty just after crossing into Northern Ireland. The below is one of the few examples I could find where the GSV imagery wasn't from around 2011. https://www.google.ie/maps/@55.0367663, ... 384!8i8192

[CrazyInWeston]

Can anyone tell me why this is sign posted as a 60 and not NSL? Granted this road is a dual carriageway and not a single, but its the same street furniture.

[Chris5156]

Can anyone tell me why this is sign posted as a 60 and not NSL? Granted this road is a dual carriageway and not a single, but its the same street furniture.

If it was NSL the limit would be 70, because it's a dual carriageway. A lower limit of 60mph has to be specifically signposted.

[CrazyInWeston]

If it was NSL the limit would be 70, because it's a dual carriageway. A lower limit of 60mph has to be specifically signposted.

Ah yeah thanks, my brain was like "well whats the difference?" but of course an NSL D2 would be 70mph, my bad.

[skiddaw05]

I haven't got the foggiest why there's one here. There's no dual carriageways or roundabouts anywhere nearby

[Ruperts Trooper]

I haven't got the foggiest why there's one here. There's no dual carriageways or roundabouts anywhere nearby

I thought there was a convention that speed camera signs should include the limit.

[jervi]

I haven't got the foggiest why there's one here. There's no dual carriageways or roundabouts anywhere nearby

I thought there was a convention that speed camera signs should include the limit.

Yes that is the case, but the speed limit here is NSL, not 60. Although they are the same, they are different.

[Conekicker]

If the sign is intended to advise of a speed camera ahead and to remind drivers that the National Speed Limit is in place, it should be a sign to Diagram 880.1.

880_1.pdf

(163.05 KiB) Downloaded 40 times

[CrazyInWeston]

The A30 in in Cornwall gives drivers those signs plenty of times before an actual camera arrives to measure speed. Why people think they are there to rip the motorist off I dont know, there are many places across the UK where it warns of a camera before there actually being one. The only difference nowadays is the ones placed on Motorway gantries. I cannot tell which ones do or dont have a speed camera attached to them. Many do have the lines on the road, but the newest ones that can track 3 lanes of traffic with one camera dont.

[Patrick Harper]

I was just thinking, shouldn't urban roads with a 30mph limit be signposted with the NSL signs instead?

[Chris5156]

I was just thinking, shouldn't urban roads with a 30mph limit be signposted with the NSL signs instead?

No, because those two signs mean different things.

Where specific local limits do not apply, a road will either be “restricted” or “derestricted”. Restricted roads have 30mph limits and are indicated by 30mph signs and usually also by the presence of street lights. Derestricted roads are indicated by the NSL roundel, and the National Speed Limit applies only to derestricted roads.

Using the same sign for both would mean that there was no clear distinction when entering or exiting a restricted road.

[Stevie D]

I was just thinking, shouldn't urban roads with a 30mph limit be signposted with the NSL signs instead?

No.
The national speed limit is 40/50/60/70mph depending on what class of vehicle you are driving and whether the road is single- or dual-carriageway, and is the maximum permissible speed limit. It is never 30mph, and it is not overridden by a higher signed limit (with the exception of specific authorised signs such as the 50 limit for HGVs on the A9).

That is different from the default speed limit. Where there is regular street lighting, the default speed limit is 30mph (ie, in the absence of any other signage or repeaters, you should assume it is 30mph), but this can be overridden by other signs giving a numerical speed or specifying that NSL applies. But on a lit road, NSL still means 40/50/60/70.

[Patrick Harper]

I was just thinking, shouldn't urban roads with a 30mph limit be signposted with the NSL signs instead?

No, because those two signs mean different things.

Where specific local limits do not apply, a road will either be “restricted” or “derestricted”. Restricted roads have 30mph limits and are indicated by 30mph signs and usually also by the presence of street lights. Derestricted roads are indicated by the NSL roundel, and the National Speed Limit applies only to derestricted roads.

Using the same sign for both would mean that there was no clear distinction when entering or exiting a restricted road.

That would make this page wrong about national speed limits applying to urban (restricted) roads.

[Chris5156]

That would make this page wrong about national speed limits applying to urban (restricted) roads.

There's a difference between the term "national speed limits", meaning speed limits that apply to all roads nationally unless replaced with a local limit, and the National Speed Limit, which is specifically the 60/70mph limit imposed on derestricted roads by Statutory Instrument. The page you linked to does not claim that 30mph is part of the National Speed Limit, but it does list it as one of the speed limits that apply nationally. It's a slightly messy use of terminology but I don't think it's actually wrong.

[Stevie D]

That would make this page wrong about national speed limits applying to urban (restricted) roads.

I believe you're right. I'm also pretty sceptical about the line "A speed limit of 30 miles per hour (mph) or 48 kilometres per hour (km/h) usually applies, unless you see signs showing otherwise", given the huge number of unlit rural roads that are subject to NSL and rightly have no repeater signs.

[AndyB]

That would make this page wrong about national speed limits applying to urban (restricted) roads.

I believe you're right. I'm also pretty sceptical about the line "A speed limit of 30 miles per hour (mph) or 48 kilometres per hour (km/h) usually applies, unless you see signs showing otherwise", given the huge number of unlit rural roads that are subject to NSL and rightly have no repeater signs.

You're correct to be sceptical - it's clearly out of place, because that statement can only apply to roads with a system of street lighting.

TSRGD defines the National Speed Limit as "any prohibition imposed on a road by the 70 miles per hour, 60 miles per hour and 50 miles per hour (Temporary Speed Limit) Order 1977 or by regulation 3 of the Motorways Traffic (Speed Limits) Regulations 1974"