NSL Logic

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Patrick Harper
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NSL Logic

Post by Patrick Harper »

Is it just me, or has the general perception of the NSL sign's meaning been speed limits for roads with no street lighting, regardless of whether a system of lighting exists? Should the 'rural' highways that currently have street lighting, e.g the trunk part of the A13, be treated with (at minimum) 40 or 50 signs instead of NSL signs, because NSL signs would communicate a 30 limit assuming the official 'logic' is applied?
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Chris Bertram
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Re: NSL Logic

Post by Chris Bertram »

Patrick Harper wrote: Fri Jun 24, 2022 15:57 Is it just me, or has the general perception of the NSL sign's meaning been speed limits for roads with no street lighting, regardless of whether a system of lighting exists? Should the 'rural' highways that currently have street lighting, e.g the trunk part of the A13, be treated with (at minimum) 40 or 50 signs instead of NSL signs, because NSL signs would communicate a 30 limit assuming the official 'logic' is applied?
I'm sure we've been over this before. NSL means the National Speed Limit, i.e. 60mph or 70mph depending on number of carriageways. 30 limits apply on Restricted Roads, which will have traffic orders to that effect. On such roads, providing there is a system of street lighting, no 30 repeaters are required (strictly none are permitted); if street lighting is absent, then 30 repeaters are required.

But there's nothing to stop street lighting being installed on unrestricted roads, and on busier roads it often is. In these cases, NSL repeaters are required so that drivers do not assume it is a restricted road. I will say that the A1 north of Red House could do with a few more of these, but thats for NH to put right.

Applying 40 or 50 limits to these rural highways seems like an odd way to "correct" what you see as a deficiency in speed limit signing; in any case such a deficiency does not exist.
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Re: NSL Logic

Post by Bryn666 »

Chris Bertram wrote: Fri Jun 24, 2022 16:23
Patrick Harper wrote: Fri Jun 24, 2022 15:57 Is it just me, or has the general perception of the NSL sign's meaning been speed limits for roads with no street lighting, regardless of whether a system of lighting exists? Should the 'rural' highways that currently have street lighting, e.g the trunk part of the A13, be treated with (at minimum) 40 or 50 signs instead of NSL signs, because NSL signs would communicate a 30 limit assuming the official 'logic' is applied?
I'm sure we've been over this before. NSL means the National Speed Limit, i.e. 60mph or 70mph depending on number of carriageways. 30 limits apply on Restricted Roads, which will have traffic orders to that effect. On such roads, providing there is a system of street lighting, no 30 repeaters are required (strictly none are permitted); if street lighting is absent, then 30 repeaters are required.

But there's nothing to stop street lighting being installed on unrestricted roads, and on busier roads it often is. In these cases, NSL repeaters are required so that drivers do not assume it is a restricted road. I will say that the A1 north of Red House could do with a few more of these, but thats for NH to put right.

Applying 40 or 50 limits to these rural highways seems like an odd way to "correct" what you see as a deficiency in speed limit signing; in any case such a deficiency does not exist.
As Chris points out, restricted roads are 30 mph and do not require signs. You don't need a speed limit order for Restricted Roads per se, the presence of a system of lighting and no signs to any other effect means 30.

That is why NSL lit roads do require signs, to demonstrate they are not restricted because they are National Speed Limit by order.
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Chris Bertram
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Re: NSL Logic

Post by Chris Bertram »

Bryn666 wrote: Fri Jun 24, 2022 16:40
Chris Bertram wrote: Fri Jun 24, 2022 16:23
Patrick Harper wrote: Fri Jun 24, 2022 15:57 Is it just me, or has the general perception of the NSL sign's meaning been speed limits for roads with no street lighting, regardless of whether a system of lighting exists? Should the 'rural' highways that currently have street lighting, e.g the trunk part of the A13, be treated with (at minimum) 40 or 50 signs instead of NSL signs, because NSL signs would communicate a 30 limit assuming the official 'logic' is applied?
I'm sure we've been over this before. NSL means the National Speed Limit, i.e. 60mph or 70mph depending on number of carriageways. 30 limits apply on Restricted Roads, which will have traffic orders to that effect. On such roads, providing there is a system of street lighting, no 30 repeaters are required (strictly none are permitted); if street lighting is absent, then 30 repeaters are required.

But there's nothing to stop street lighting being installed on unrestricted roads, and on busier roads it often is. In these cases, NSL repeaters are required so that drivers do not assume it is a restricted road. I will say that the A1 north of Red House could do with a few more of these, but thats for NH to put right.

Applying 40 or 50 limits to these rural highways seems like an odd way to "correct" what you see as a deficiency in speed limit signing; in any case such a deficiency does not exist.
As Chris points out, restricted roads are 30 mph and do not require signs. You don't need a speed limit order for Restricted Roads per se, the presence of a system of lighting and no signs to any other effect means 30.

That is why NSL lit roads do require signs, to demonstrate they are not restricted because they are National Speed Limit by order.
I wondered about that, but surely the creation of a Restricted Road must involve some sort of formal designation as such?
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Bryn666
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Re: NSL Logic

Post by Bryn666 »

Chris Bertram wrote: Fri Jun 24, 2022 16:42
Bryn666 wrote: Fri Jun 24, 2022 16:40
Chris Bertram wrote: Fri Jun 24, 2022 16:23 I'm sure we've been over this before. NSL means the National Speed Limit, i.e. 60mph or 70mph depending on number of carriageways. 30 limits apply on Restricted Roads, which will have traffic orders to that effect. On such roads, providing there is a system of street lighting, no 30 repeaters are required (strictly none are permitted); if street lighting is absent, then 30 repeaters are required.

But there's nothing to stop street lighting being installed on unrestricted roads, and on busier roads it often is. In these cases, NSL repeaters are required so that drivers do not assume it is a restricted road. I will say that the A1 north of Red House could do with a few more of these, but thats for NH to put right.

Applying 40 or 50 limits to these rural highways seems like an odd way to "correct" what you see as a deficiency in speed limit signing; in any case such a deficiency does not exist.
As Chris points out, restricted roads are 30 mph and do not require signs. You don't need a speed limit order for Restricted Roads per se, the presence of a system of lighting and no signs to any other effect means 30.

That is why NSL lit roads do require signs, to demonstrate they are not restricted because they are National Speed Limit by order.
I wondered about that, but surely the creation of a Restricted Road must involve some sort of formal designation as such?
Section 82 of the RTRA 1984 simply says if there's a system of lighting, it becomes 30. Presumably documents for new roads refer to S82 being applicable.

Where this gets very messy is unlit roads being given lighting - as happened in parts of Calderdale - but no signs were installed at the end of the lit sections. We had to fine tooth comb many roads for this reason.
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Re: NSL Logic

Post by Patrick Harper »

So Figure 671 for roads like trunk A13 actually means 'this highway, regardless of the presence of street lighting, has the same restrictions as those applied to formerly de-restricted highways'?
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Re: NSL Logic

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Patrick Harper wrote: Fri Jun 24, 2022 19:41 So Figure 671 for roads like trunk A13 actually means 'this highway, regardless of the presence of street lighting, has the same restrictions as those applied to formerly de-restricted highways'?
No it says the road runs here, just as diversion signs do. I doubt too many civilian policemen would try and flag down a military convoy. That would be left to the RMP (Royal Military Police). By 1944 there were 50,000 of them.
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Re: NSL Logic

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Patrick Harper wrote: Fri Jun 24, 2022 19:41So Figure 671 for roads like trunk A13 actually means 'this highway, regardless of the presence of street lighting, has the same restrictions as those applied to formerly de-restricted highways'?
Yes. There is a distinction between "desrestricted" roads, now subject to the National Speed Limit, and "restricted" roads, subject to the 30mph limit. The white circular sign with a black diagonal bar means you are entering a "derestricted" road, ie one subject to a 60 or 70mph speed limit. It never implies a 30 limit, the only sign that can do that is a red ring with "30" inside it.
KeithW wrote: Fri Jun 24, 2022 20:09
Patrick Harper wrote: Fri Jun 24, 2022 19:41 So Figure 671 for roads like trunk A13 actually means 'this highway, regardless of the presence of street lighting, has the same restrictions as those applied to formerly de-restricted highways'?
No it says the road runs here, just as diversion signs do. I doubt too many civilian policemen would try and flag down a military convoy. That would be left to the RMP (Royal Military Police). By 1944 there were 50,000 of them.
I think you're in the wrong thread there, Keith!
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Re: NSL Logic

Post by Vierwielen »

I lived in South Africa during the oil crisis of the mid-1970s. In order to preserve fuel a blanket speed limit of 80 km/h was imposed on rural roads and 50 km/h on urban roads with draconian fines for breaking the speed limit. The normal urban speed limit was 60 km/h. The government, in their haste, had forgotten about urban motorways etc and there was general chaos because nobody in the main cities knew what the speed limits were on urban morotways. Eventually the government got some sense into their heads and revised the speed limit rules - effectively posted speed limits applied except that all speed limits above 90 km/h were deemed to be 90 km/h.

The existance of a NSL means that in events such as this, the maximum speed can be varied at the stroke of a pen (and appropriate publicity). Also, if there is a decision to go over to km/h (not that I am expecting anything like this while Boris is around), it will not be necessary to change hundreds of 70 mph signs to 120 km/h signs and hundreds of 60 mph signs to 100 km/h signs.
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Re: NSL Logic

Post by KeithW »

Chris5156 wrote: Fri Jun 24, 2022 20:57
I think you're in the wrong thread there, Keith!
Yep my mistake.
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Re: NSL Logic

Post by Herned »

I wonder what proportion of drivers are even aware that streetlights means there is a 30mph limit? (Unless otherwise signed)
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Re: NSL Logic

Post by Ruperts Trooper »

Herned wrote: Sat Jun 25, 2022 13:30 I wonder what proportion of drivers are even aware that streetlights means there is a 30mph limit? (Unless otherwise signed)
Not many, judging by responses on the Speed Awareness course I was on :oops:
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Re: NSL Logic

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Herned wrote: Sat Jun 25, 2022 13:30 I wonder what proportion of drivers are even aware that streetlights means there is a 30mph limit? (Unless otherwise signed)
About the same number who think that absolutely any road with a central reservation is 70mph or no limit, I expect...
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Re: NSL Logic

Post by ajuk »

I don't know if it's a recent thing, but South Gloucestershire have been forced remove 30mph repeaters on roads with street lights. Are the DfT enforcing this rule now? It's a shame they can't also enforce speed limit setting guidelines. Although I've noticed Highways England have stared to disregard these now putting in an arbitrary "buffer zone" and ridding the preceding village of it's drop in speed limit in a place where it clearly makes sense.
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Re: NSL Logic

Post by Vierwielen »

ajuk wrote: Thu Jun 30, 2022 01:39 I don't know if it's a recent thing, but South Gloucestershire have been forced remove 30mph repeaters on roads with street lights. Are the DfT enforcing this rule now? It's a shame they can't also enforce speed limit setting guidelines. Although I've noticed Highways England have stared to disregard these now putting in an arbitrary "buffer zone" and ridding the preceding village of it's drop in speed limit in a place where it clearly makes sense.
But what happens if they turn those lights off at 02:00 to save energy? How are motorists expected to know that they are in a 30 mph zone?
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Re: NSL Logic

Post by Kevin Roads »

Whilst I understand that a system of streetlighting indicates a 30mph limit (unless otherwise signed) and, therefore, no repeaters are needed (nor even permitted, as I've discovered from this thread), is there a requirement for a large 30 sign at the start of the limit? I can't recall any 30mph roads that don't have one (cue loads of posts with examples, as usual).
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Re: NSL Logic

Post by KeithW »

Vierwielen wrote: Thu Jun 30, 2022 08:31 But what happens if they turn those lights off at 02:00 to save energy? How are motorists expected to know that they are in a 30 mph zone?
Its still a 30 zone

See Road Traffic Regulations Act 1984 Section 1982
What roads are restricted roads.
(1)Subject to the provisions of this section and of section 84(3) of this Act, a road is a restricted road for the purposes of section 81 of this Act

(a)in England and Wales, there is provided on it a system of street lighting furnished by means of lamps placed not more than 200 yards apart;
( b )in Scotland, there is provided on it a system of carriageway lighting furnished by means of lamps placed not more than 185 metres apart and the road is of a classification or type specified for the purposes of this subsection in regulations made by the [F2Scottish Ministers] .]
There is no reference to the lighting system being in use otherwise whenever the lights were not on either turned off or due to a power cut etc the NSL would apply. It quite common with large scale housing developments that the connecting up and activation street lights is one of the last things completed.

This happened in the case of the new town of Cambourne South Cambridgeshire was built but before it was adopted the lamp posts were in place but had no lanterns and were not connected. The developers wanted to put up speed limit signs but none were legally applicable so they put signs indicating an unenforceable 19 mph speed limit.

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Re: NSL Logic

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Patrick Harper wrote: Fri Jun 24, 2022 15:57 Is it just me, or has the general perception of the NSL sign's meaning been speed limits for roads with no street lighting, regardless of whether a system of lighting exists? Should the 'rural' highways that currently have street lighting, e.g the trunk part of the A13, be treated with (at minimum) 40 or 50 signs instead of NSL signs, because NSL signs would communicate a 30 limit assuming the official 'logic' is applied?
It's not just you. The issue stems from referring to the limit of 30 for roads with street lights as a "national speed limit".
https://www.gov.uk/speed-limits wrote: National speed limits
A speed limit of 30 miles per hour (48km/h) applies to all single and dual carriageways with street lights, unless there are signs showing otherwise.
If that's the case, then a "national speed limit applies" sign on a road with street lights indicates a 30 limit!

I'm sure I remember as a child seeing this image in the Highway Code:
Image

As a child, I remember Park Hall Road (A5272) in Stoke on Trent having NSL repeaters attached to its street lights, and arguing with my dad that the "national speed limit" that applied was technically 30 because of the street lights!

I think the previous thread on this subject suggested there was a difference between "National Speed Limit" and "national speed limit", where 30 is only a "national speed limit", and the NSL sign means the former. As if that's a reasonable explanation to present to the general public!
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Re: NSL Logic

Post by trickstat »

Vierwielen wrote: Thu Jun 30, 2022 08:31
ajuk wrote: Thu Jun 30, 2022 01:39 I don't know if it's a recent thing, but South Gloucestershire have been forced remove 30mph repeaters on roads with street lights. Are the DfT enforcing this rule now? It's a shame they can't also enforce speed limit setting guidelines. Although I've noticed Highways England have stared to disregard these now putting in an arbitrary "buffer zone" and ridding the preceding village of it's drop in speed limit in a place where it clearly makes sense.
But what happens if they turn those lights off at 02:00 to save energy? How are motorists expected to know that they are in a 30 mph zone?
If they can't see that there are streetlights present with their headlights on perhaps they shouldn't be driving at night?
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Re: NSL Logic

Post by skiddaw05 »

deadly wrote: Thu Jun 30, 2022 09:59 As a child, I remember Park Hall Road (A5272) in Stoke on Trent having NSL repeaters attached to its street lights, and arguing with my dad that the "national speed limit" that applied was technically 30 because of the street lights!
Maybe the street lights were more than 200 yards apart!
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