Okay, I have the impression that the tenor of the answers I got so far is that a "maxspeed:type=GB:something" tagging would not be necessary because in practice in the UK, any 30mph limit on lit streets will be posted explicitly. Thus, the maxspeed should be specified explicitly (along with "maxspeed:type=sign").
To those who find I summed up their opinion on that matter correctly, I would like to confront you with an actual problem I encountered with the surveyor-app StreetComplete of which I am the author of. I linked the ticket to this issue in my original post. I am quite sure that this problem can lead to wrong tagging, specifically that normal urban roads, even residential ones, are tagged with "maxspeed:type=nsl_single" when they should not. So I very much want to solve this problem as soon as possible and I am hoping you can help to find a solution to it and/or understand my point of view that *some* "maxspeed:type" or similar tagging might be necessary. I will now explain how this mistagging might come about in the dialogue of the user with the app: The app shows the street section which it is about highlighted and asks: *"What is the speed limit sign for this street?"* The user can then either fill in an explicit speed limit or answer "There is no sign". So, in case the user does not see any sign, as he would on a typical British urban street, he answers: *"There is no sign"* The app asks: *"Are you sure no limit is posted? Did you check at the ends of the street? If there are no signs along the whole street which apply for the highlighted section, default speed limits apply."* ...and in case of a road tagged as residential, it shows a slow-zone sign and adds: *"If there is a sign like this at the main street intersection, you won't find individual signs within the zone because the speed limit posted there applies to the whole zone."* When the user answers *"Yes, no sign"*, the app just asks (for GB): *"Are the carriageways of this road here physically separated (i.e. through a barrier)? The default speed limit depends on whether this is the case or not."* The app then tags "maxspeed:type=nsl_single" or "maxspeed:type=nsl_dual" based on the user's answer. So, if I understand correctly, this "default 30mph limit" within lit sections of British roads is always signed, yes, but otherwise behave like 20mph zones in that there are no repeater signs at intersections and *not even* in roads that branch of this main road and roads that branch of the branched off roads (right?). This would mean, that in Britain, it is not enough to tell the user to look for a sign at the start of the road, but to, well, what exactly? This is where I need your help. How should the dialog be changed (in GB) to not create any misunderstandings here? Tobias On 30/04/2018 19:41, Tobias Zwick wrote: > Hi there > > On tagging implicit speed limits in the United Kingdom, the wiki lists > the following values [1] for "maxspeed:type": > > GB:nsl_single (=60 mph), GB:nsl_dual (=70 mph) and GB:motorway (=70 mph) > > I understand that the current legislation defines a road with > road-lighting as a built-up area in which a lower implicit speed limit > of 30 mph applies. There is no mention of it in the wiki, no GB:urban, > GB:lit, GB:zone30 or anything like that, so something should be defined > and documented by (you,) the British OSM community. > > My question: > How to tag roads in which such an implicit speed limit for built-up > areas applies? > > The question is motivated by an issue report for StreetComplete [2] > > Cheers > Tobias > > [1] > https://wiki.openstreetmap.org/wiki/Speed_limits#Country_code.2Fcategory_conversion_table > > [2] https://github.com/westnordost/StreetComplete/issues/1037 > > _______________________________________________ > Talk-GB mailing list > Talk-GB@openstreetmap.org > https://lists.openstreetmap.org/listinfo/talk-gb > _______________________________________________ Talk-GB mailing list Talk-GB@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk-gb
