[OSM-talk] OpenRailwayMap Electrification Status vs tag electrification=no

[stevea]

On Feb 23, 2022, at 3:58 PM, Michael Reichert <osm-ml at michreichert.de> wrote:
> you mean electrified=contact_line/rail/no/…, don't you? The key electrification=* exists 4 times in OSM but electrified is used by 1.9 million objects. electrified=* is used by the electrification style of OpenRailwayMap and the tag is in use for more than 10 years by mappers (the style is not as old).

Hello, Michael, thank you for your correction!

> For me, oneway=no and electrified=no are similar but different. oneway=yes is assumed as default for roads but there is no default electrified=*. As a cycleway mapper, I use oneway=no very often but on highway=footway/path/cycleway only because you may not use cycleways on the left side of the road in Germany except explicitly permitted by sign.

I'm speaking for myself here, but I'm aware of many other USA-based mappers who think this way (I'm pretty sure, if not, I'm going to get a lot of rocks thrown at me here and soon!) but I assume as default for roads oneway=no, except for the dual carriageways of a motorway, where it is always set to oneway=yes on the portion (EACH portion) which IS oneway.

So, we can see how many assumptions vary around the world, and I would assume, even among individual mappers in any given part of the world.

> The map style distinguishes between tracks which are not electrified and those where this information has not been mapped yet (e.g. survey or, in some cases, aerial imagery). The tag is as important as gauge=* (whose main value is 1435 except certain countries).

I think the important point here, not just for rail or oneway but for any or all tags is what Michael says here:  "where this information has not been mapped yet."  There are plenty of these sorts of "empty" tags, where the simple semantic of "no tag" means that particular datum "hasn't yet been entered into OSM."