Talk:Key:source:maxspeed

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maxspeed:source

I would prefer to use maxspeed:source. So it's possible to use a common name space with other maxspeed-tags.--Falcius 09:24, 14 March 2010 (UTC)

I would also prefer this version. It is normal to tag the main-tag first and then the special part. (E.g. http://wiki.openstreetmap.org/wiki/Proposed_features/Extended_conditions_for_access_tags [maxspeed:hgv=xyz]) Snoopy88 09:51, 14 March 2010 (UTC)
The same reasoning applies for the other order, too: all sources together with a common beginning. In the end it's a matter of what get's supported in some or any software and/or what get's used more often. Until that time it's only a matter worth a mention (which this discussion page section accomplishes). Alv 12:00, 14 March 2010 (UTC)
No, the source describes a detail of the maxspeed => maxspeed ist the main-tag. Also in maxspeed:hgv you describe a detail of the maxspeed tag. If you say source:maxspeed, you would describe the maxspeed of the data-source. If we have the maxspeed-tag, all detailed information should be below this tag. Snoopy88 15:05, 14 March 2010 (UTC)
Are you suggesting that source:ref=* and source:name=* should become ref:source=* and name:source=*? --goldfndr 16:20, 14 March 2010 (UTC)
If you think we are right with maxspeed:source it's up to you to propose it for source:ref and source:name=, too.--Falcius 17:50, 14 March 2010 (UTC)
I think that source:maxspeed is better, and it is currently outside Australia far more in use then maxspeed:source. The main tag is source, because it is a source, maxspeed:hgv is for example the maxspeed for hgv, in this logic maxspeed:source would be the maxspeed for the source ;-) -- Dieterdreist 15:44, 19 January 2011 (UTC)

zone signs?

What is a "zone" sign? Is this perhaps comparable to an "area speed limit" in the US, where a sign indicates that all the streets in a particular area have the same default limit? Nfgusedautoparts 19:53, 15 April 2011 (BST)

Yes, normal maxspeed sign loose its weight after turning. Zone-signs only loose its weight after a zone-end-sign (See wikipedia:Road_signs_in_Germany sign 274.1 and 274.2) --phobie m d 19:14, 26 July 2011 (BST)

Speed limit signs are normally double sided

Has anyone considered how to map zone changes - for example moving from a 30 to a 40 zone. The side of the road is important, the direction of travel is important, and there may well be more than one sign effecting the opposite traffic flow. Essjayhch 11:10, 26 September 2011 (BST)

For maxspeed signs I usually use a double approach, tagging also the traffic sign positions by adding a node at the side of the way (to store also the direction, better don't put it on the way): traffic_sign=maxspeed and maxspeed=* --Dieterdreist (talk) 17:20, 20 March 2013 (UTC)
Speed limits in the areas I am aware of are normally not double-sided and the limits usually change at different spots, depending on the direction of travel. There are maxspeed:forward=* and maxspeed:backward=* tags for these "asymmetric" speed limits. --Dieterdreist (talk) 10:49, 27 May 2017 (UTC)

Directing people to speed limits article

It seems very confusing and inefficient to have two pages describing rival ways to do the same thing. As such I have reduced the scope of this article to a brief summary of the two current uses for this tag with a link to Speed limits and talk:Speed limits for more information and any discussion on how to resolve this. I have done the same with maxspeed:type=*. PeterIto (talk) 01:25, 24 February 2013 (UTC)

A subsequent discussion thread, now titled 'Preference for using source:maxspeed to hold the legal form of the speed limit' has been moved to talk:Speed limits to keep all the discussion in one place as per explanation in that thread. PeterIto (talk) 04:19, 27 March 2013 (UTC)
I have set up this page years ago after discussion on the italian, the tagging and the german mailing list as by that time there was uncertainty how to do it. Also by that time there was no other usage of this tag. We have subsequently tagged a lot of roads according to this scheme and documented usage here in the wiki. The scheme was adopted by mappers in other countries. I do not think it is helpful to insist that this tag is disputed or unclear. Still today out of 330.000 times used there is only 10000 times "survey". I really don't see why those who still want to tag sources on objects (despite this is for long discouraged in general) have to insist in using this tag and cannot use "maxspeed:source" or something else. I also don't want to change wikipages due to widely undiscussed imports that slightly distort the usage image, but luckily don't achieve in doing it completely. FYI, this page was set up first, and if others have decided to invent a rivalling scheme it is them who should think about the efficiency of their work. --Dieterdreist (talk) 13:05, 2 December 2013 (UTC)

country-specific zones?

I suggest omitting country codes for designated zones. E.g. source:maxspeed=zone instead of source:maxspeed=DE:zone. As far as I know, there's nothing country-specific in these zones. A 30 km/h zone in Germany is exactly the same thing as a 30 km/h zone in Uganda. --Fkv (talk) 14:51, 17 September 2014 (UTC)

Are you sure that the zones are exactly identical? For example, in Germany a 30 km/h zone does not just mean a maxspeed of 30 km/h, it also means that there is a "left yields to right" rule at all junctions within the zone, and there must not be obligatory cycleways within the zones. I consider it unlikely that such additional implications are globally consistent. --Tordanik 16:07, 17 September 2014 (UTC)
That's probably true (in Hungary I don't think there is any such direct implication, essentially you use this rule whenever no one has a yield or stop sign). But I doubt source:maxspeed is the right tag to store that information in. I would probably tag the rule somehow at each of the junctions. I agree with Fkv: I think both the country code and the speed limit are superfluous in the source tag, just like when the source is a sign. So instead of HU:sign60 and HU:zone30, I just use sign and zone. – kdano * 22:40, 16 November 2014 (UTC)
The "left yields to right" applies to whole Germany unless there's a sign or the right-hand road is a track (§ 8 StVO). I doubt that a 30 km/h zone invalidates that rule. § 45 Abs. 1c only states that "innerhalb der Zone muss grundsätzlich die Vorfahrtregel nach § 8 Absatz 1 Satz 1 („rechts vor links“) gelten", which means that administrative authorities shall not put give-way signs there. If they put or leave a give-way sign there by mistake, you as a road user certainly have to obey that sign. The same for cycleways. The relevant phrase in § 45 Abs. 1c only tells authorities where they are allowed to establish zones. It's nothing we need to consider in OSM, unless authorities use OSM to decide where to set up 30 km/h zones or where to put give-way signs. But even if they do so, they can take the information from maxspeed=30 and source:maxspeed=zone (or maxspeed:type=zone). They do not need speed and country redundantly tagged. --Fkv (talk) 12:54, 27 January 2015 (UTC)
In France for instance, any road within a zone 30 can be used in both direction by cyclists. I don't know if this is valid in Germany, Hungary or elsewhere. For France, in theory it could make oneway=yes, oneway:bicycle=yes redundant but probably an help to tag it inside the area as most rendering engines and routing engines don't know this specificity.
--Nospam2005 (talk) 15:18, 12 August 2018 (UTC)
That law is similar to the one in Austria concerning living streets, see note #4 on OSM tags for routing/Access-Restrictions#Austria. (I suggest you add the French exception in the same way to the section on France). As you wrote below, country code can derived from geometry. Routing applications need to do that anyway (for all of the other country-specific access and maxspeed defaults). The country code in source:maxspeed provides just an alternative but less reliable source to get to the same information. I'd also like to point out that source:maxspeed is about maxspeed and not about access. Using source:maxspeed to determine possible driving directions for cyclists is just a hack that works with French 30 km/h zones but wouldn't work with Austrian living streets. As the hack for France does not really need the country code, I suggest to leave the source:maxspeed value as simple as it can be with respect to its actual meaning. --Fkv (talk) 16:51, 12 August 2018 (UTC)
I agree that checking the country from polygons would work also, but I would question the statement it is more reliable. —Dieterdreist (talk) 21:32, 12 August 2018 (UTC)
There will always be roads with missing source:maxspeed tags or with "wrong" values. Keep in mind that it is a free-text field, and people type in whatever they like. Of course, multipolygons can be broken, but country MPs use to get fixed quickly. I can't remember having ever seen a country MP severely broken on OSMI. --Fkv (talk) 22:30, 12 August 2018 (UTC)
Fkv, you can't say at the same time that source:maxspeed should only mean zone (here) and ask to modify the page on highways, as highway does not have the information about FR:zone30. So you mention we should not convey more information than just the reason of the speed limit. Then maxspeed=VALUE, source:maxspeed=zone (as you suggest below) makes sense but there is no information on the highway page except if stating that maxspeed=30 and source:maxspeed=zone implies cycleway=opposite. This does NOT depends on the type of highway! A proper solution would to map the zones as we do map administrative boundaries (a big change - it would make source:maxspeed=zone superfluous BTW!) or to introduce highway=calm_street or zone30. Or tage zone=FR:zone30 (for instance).
--Nospam2005 (talk) 10:35, 15 August 2018 (UTC)

maxspeed zones

TLDR: Should this be the new default for maxspeed limit zones:

  • maxspeed=VALUE
  • source:maxspeed=zone
  • zone:maxspeed=COUNTRY:VALUE


The long story is that there are mutiple variants of maxspeed uses in zones which is not applicable for OSM in terms of reusing it on other platforms or devices. Imagine a zone with maxspeed 30 in germany. This is may tagges as one of the listed below:

  • maxspeed=30 + source:maxspeed=zone
  • maxspeed=30 + source:maxspeed=DE:zone30
  • maxspeed=30 + source:maxspeed=DE:zone:30
  • maxspeed=30 + source:maxspeed=zone + zone:maxspeed=DE:30
  • any combination with maxspeed:type instead of source:maxspeed


I'm in favour of the last one since it's the most flexible one without jamming every possible information into one key. Any comments/ideas?
--TBKMrt (talk) 14:07, 12 August 2018 (UTC)

Only the first option (source:maxspeed=zone or maxspeed:type=zone, without zone:maxspeed=*) seems reasonable to me. The country prefix is useless because 30 km/h zones are the same all over the world. The ":30" suffix is redundant to maxspeed=30. Wherever redundant tags are used, you have to expect inconsistencies (e.g. maxspeed=50 + source:maxspeed=DE:zone:30 on a road in Nigeria) and appications have to work out how to handle them, which is an annoying task.
I see little benefit in adding tags like zone:maxspeed=* as long as they increase complexity (think of maxspeed:backward, maxspeed:conditional etc.) without providing any additional information, let alone a solution to the nested zones problem. For the latter, you need a more sophisticated tagging scheme, with multi-value strings at least.
--Fkv (talk) 15:08, 12 August 2018 (UTC)
at the same time I was writing to the previous section that Zone 30 in France is not the same as in Germany, making your point pointless (maxspeed=30 + source:maxspeed=zone is not a good option). I prefer the second option (maxspeed=30 + source:maxspeed=DE:zone30). In July 2018, the French government changed the maximum speed of FR:rural to 80 km/h (with a few exceptions). Having the source (sign or here origin of the default value) helps to enhance tagging (see previous section) or perform updates. Of course country code can be derived from geometry.
Taginfo shows that DE:zone30 is more used than DE:zone:30, same for FR:zone30, PL:zone30, NL:zone30...
--Nospam2005 (talk) 15:40, 12 August 2018 (UTC)
The reason for the country prefix was more reliability when you are close to a border. With perfect boundaries it should not be necessary, but boundaries break quite often and might not everywhere be in a high resolution. I don’t believe we should need more than 2 tags for a zone-inferred maxspeed, keep it simple. —Dieterdreist (talk) 16:05, 12 August 2018 (UTC)
+1, it makes also directed updates easier, as in my example checking maxspeed=90 where source:maxspeed=FR:Rural --Nospam2005 (talk) 16:17, 12 August 2018 (UTC)