Re: [Talk-GB] inferred single-carriageway NSL?

[Ian Spencer]

Kevin Peat wrote on 16/03/2011 17:27: On 16 March 2011 17:00, Peter Miller <peter.mil...@itoworld.com> wrote: Then there are the '30mph' which should for consistency be '30 mph' (with a space). I don't see the point of editing just for consistency. Developers should handle leading/trailing spaces, or the lack thereof, and different capitalisation, as without any input validation the data will always be inconsistent.   Finally, I have a technical question on speed limits. What exactly is a dual carriageway? Are the slip-roads between two dual carriageways also dual carriageways (and therefore have 70mph limits) or are they not and are they therefore 60mph limits? Similarly for short sections where a single carriageway road divides for a short section. I am also curious about this. There is a dual carriageway near me that has 3 roundabouts along its length. Two of the roundabouts have signed 40mph limits but the third one has no signed limit. I assume the limit for that roundabout is 60mph? Kevin I think the definition depends on physical separation, so I'd say that the roundabout is 70mph as the two flows are still physically separated - OTOH there is a bit that isn't... generally the physical constraints of traversing a roundabout make this a moot point. A slip road is divided from oncoming traffic, so it would be deemed to be 70mph. Of course, a speed limit does not indicate a safe speed of travel, so if a policeman got upset at you, he has a variety of other tools in his armoury to exact a punishment for anyone who gets pedantic. If the carriageway divides for a short way, e.g. for a junction, then the speed limit rises. Similarly, if they illuminate a junction, with lights at the required spacing, it is a de facto 30mph. That is why you will normally find such sections of roads acquire repeater signs. (It is mistakenly assumed that the street light rule only applies in built up areas).

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