[Tagging] Primary or Trunk?

Fernando Trebien fernando.trebien at gmail.com
Sun Nov 3 17:35:47 UTC 2013

Hello fly,

Thank you for your concern. I'm glad we agree that classification is a
hard topic sometimes. First, the graph is intended for mapping within
Brazil and not overseas. I don't wanna delve too deeply in the details
of our discussion (it would probably be long, boring and maybe only
interesting for Brazilians themselves), but I can assure you that when
we established those definitions we were trying to make our mapping
style as compatible with the rest of the world as possible. And by
"we" I mean I was not alone - many active users participated, the
graph had many "candidate" forms before we agreed this was probably
the best we could do for now. Best in terms of balancing clarity
(objectivity), complexity (how hard is the decision-making process)
and quality of the end result (the map). The graph hasn't changed in
the last 6 months and we only have two Brazilian-borne complaints in
queue since then, one of which is minor, the other a little harder
(but already being addressed) and none related to living streets.

So, you're right, living streets do not exist in Brazil according to
the strictest definitions of OSM (a legally designated road where
pedestrians have right of way over cars). However, I disagree that
they should not be used here at all. Brazil has no "primaries",
"secondaries" or "tertiaries", it has arteries, collectors and local
streets, national, state and municipal roads, and so on. These
concepts are mapped to OSM, with local adaptations, right? Many
definitions are left open in OSM; for instance, we had heated debates
on how to distinguish track, path and footway. When we reached out for
the international community, we discovered that each country has its
own definition, often more or less incompatible with that of other

Then, there are a few people who think it is useful to map the concept
of "living streets" to some sort of warning system for drivers. Those
who would benefit most from this would be tourists, certainly. There
are places with poor infrastructure that simply force pedestrians to
share space with vehicles. There are places where this sharing is
simply part of the local culture. For all practical matters, these
places function pretty much like living streets (heavy pedestrian
traffic sharing space with vehicles, which are then forced to slow
down considerably), just without the legal requirement. A distracted
driver that does not know these facts has a higher chance of causing
an accident. And if the driver knew about these streets beforehand,
he/she would usually prefer to avoid them, thus affecting routing
decisions. All that is valuable local knowledge.

On Sun, Nov 3, 2013 at 12:10 PM, fly <lowflight66 at googlemail.com> wrote:
> Am 02.11.2013 20:43, schrieb Fernando Trebien:
>> I know that in Germany and in Argentina roads are being classified
>> based primarily on administration level (national, regional, city,
>> etc.). Classifying like this probably works well when the entire road
>> system is well maintained.
>> In Brazil, however, we had tons of discussions on how to do it and
>> ended up deciding (though reluctantly) to classify based on several
>> objective structural characteristics that seemed closely related to
>> "importance". That is mostly because many regional/municipal roads are
>> definitely more important (thus, preferable) than other, smaller
>> national roads. Here's what we ended up with:
>> http://i.imgur.com/YH8azIA.png
> Please, do not use living_street the way you have it in your picture.
> Living_street is a special case and has to be signed individually.
> It is one major mistake in OSM-Historie and should be changed to
> highway=*, living_street=yes like motorroad and bicycle_road.
> As already said, if one classification does not exist in a country just
> do not use it.
> On the other hand classification is not always that easy and if politics
> get involved it gets even more tricky.
> In my area traffic was split on two roads running almost parallel but
> one has a restriction on weight. I ended up with two primaries as one
> has much traffic but the otherone is the route for hgv.
> Cheers
> fly
> _______________________________________________
> Tagging mailing list
> Tagging at openstreetmap.org
> https://lists.openstreetmap.org/listinfo/tagging

Fernando Trebien
+55 (51) 9962-5409

"The speed of computer chips doubles every 18 months." (Moore's law)
"The speed of software halves every 18 months." (Gates' law)

More information about the Tagging mailing list