[OSM-talk-be] Conventions

[Ben Laenen]

On Wednesday 27 August 2008, spam at daxu.be wrote:
> Hello,
>
> Today I was reading the conventions published on
> http://wiki.openstreetmap.org/index.php/WikiProject_Belgium/Conventio
>ns . I think we shouldn't stick to much on the N numbers to determine
> the highway type. Also in reality not all Rx streets should be
> classified as a motorway.

Yeah, that's an error in that table, there's also the R0 which isn't a 
motorway in the south of Brussels.

Anyway, the highway classification hasn't been standardized properly in 
Belgium, and usually anyone does how he/she sees fit. What's in that 
table only gives an idea about it.

Unfortunately we lack the real classification data to do it properly. In 
some government documents you can find mentions of it (goes from Lokaal 
I, II, III to Secundair I, II, Primair I, II and Hoofdweg IIRC), but in 
general finding the classification of a certain road is impossible.

So, we get influenced by what we can know: the highway numbers. There's 
also a classification for them: Nx is the first network, Nx0 is the 
second network, Nxy (y not 0) the 3rd, and Nxyz the 4th. Then making 
the first three primary and the fourth one secondary more or less works 
to get nice maps so far.

So I usually start from that classification and I upgrade or downgrade 
if it makes sense in some places. And I adjust once the bigger picture 
can be seen. In a city I usually downgrade for example.

> A N-example:
> N382 and N43 in Waregem. The N382 has 2 lanes each way, the N43 has
> only one way each way. Folling the conventions the bigest road should
> be tagged secondary and the smalest one primary. Rather weird no?

Yeah, although it's also not the case that a four-lane road always is 
more important than a 2-lane road. There are many things that would 
make a proper classification, and layout is just one of them.

If someone is able to find a resource for the official classification, 
great, but as long as that's not the case we have to keep some kind of 
personal opinion on certain roads, since I don't think it's possible to 
come up with a good working formal classification based just on the 
things you can see (and that includes car counting :-) )...

Greetings
Ben