[Tagging] Track grades

[Ole Nielsen]

On 09/07/2014 01:08, David Bannon wrote:
>
> I don't really care exactly how it is done as long as we end up with a
> clear model advising people whether or not they should attempt a
> particular road. I have posted references to lost lives as a result of
> bad decisions. Its easier to get people to take notice of simply
> presented data. Too much detail scares most people ....
>
> My pet solution was based around tracktype= with two legs, (a) we
> reassert that tracktype= applies to all highway=, not just
> highway=track. This was the original intention. (b) extend the five
> grades by another three, being 4wd recommended, required and extreme.

This would completely redefine the current meaning of tracktype which I 
think would be a very bad idea considering the widespread use of this 
tag. Extending with new values that are of a completely different class 
than the current values would be confusing.

>
> Another approach is to make wider use of 4wd_only=yes. Extend it to have
> the 'recommended' and 'extreme' values. I was advised that tags starting
> with a number were a problem in mapnik but others have dismissed that
> and a new default render has taken over now.
>
> I prefer the tracktype= model as it has pretty wide use world wide,
> 4wd_only= does not yet get much use outside of Australia.
>
> Please see Unsealed and 4wd roads in -
> https://wiki.openstreetmap.org/wiki/Talk:Australian_Tagging_Guidelines
>
> Some more ranting on my wiki page (inc discussion)
> https://wiki.openstreetmap.org/wiki/User:Davo

Instead of trying to tweak existing tags I would propose a new tag to 
indicate suitability for different types of vehicles. The following 
scheme can be applied to all unpaved highway types.

vehicle_suitability=
class 1: The road is suitable for 2WD vehicles with normal clearance.
class 2: 4WD recommended. 2WD vehicles only with experienced driver.
class 3: 4WD required. 2WD vehicles unlikely to be able to pass.
class 4: 4WD and high clearance required.

I think this should fit most dirt roads and tracks around the world. 
Would it be worth a proposal?

Ole