[OSM-talk] railway=narrow_gauge

[Adrian Frith]

On Tuesday 19 June 2007 15:51:00 Laurence Penney wrote:
> Compared with roads, it's typically very easy to find out the exact
> gauge of any railway. As an example, in less than a minute I found out
> the gauge of the Ffestiniog Railway from their website: 22.5 inches.
>
> So my vote is for:
>
> gauge=22.5in (using 'in' or 'mm' as units)
>
> We'd obviously not desire this key/value for "standard gauge" railways
> = 4ft 8½ in = 1435 mm.

The problem with that solution is that not all countries have 4ft 8.5in as 
their standard gauge. In South Africa, for example, the standard gauge is 3ft 
6in. So, you cant set up rules that say "Everything with gauge_mm=1435 draw 
as standard railway; everything with gauge_mm<1435 draw as narrow-gauge 
railway", because it'll be wrong in many cases.

How about:
railway=rail
gauge_rel=(narrow|standard|broad) [defaulting to standard]
gauge_mm=1435 [or whatever the gauge is].

That way, you know both the actual gauge and whether it's different from the 
standard for that location.

Regards,
Adrian

-- 
Adrian Frith
adrian at frith.co.za
http://adrian.frith.co.za/
+27 83 393 1257