Hello
In my country vehicle registration plates start with prefix depending on region of country.
We (polish community) would like to tag it under boundary=administrative of corresponding administrative area, but there is no established tagging for that yet.
In Taginfo I found vehicle_plate_code=* and license_plate_code=*. In our discussion vehicle_plate_indicator=* was also proposed, and I am thinking about sth like vehicle_plate_prefix=* (but I don’t know if it is prefix for other countries).
Do you have any suggestions for tagging? What would you recommend?
In my country first letter of registration plate corresponds to admin_level=4 and next 1 or 2 letters corresponds to admin_level=6
Whatever you do: Do not create new polygonal boundaries for areas relating to number plate assignment; these will almost certainly be not verifiable on the ground, and be too unimportant to claim the same exemption as administrative boundaries.
If you can get away with adding a tag to an existing administrative boundary then I guess it’s ok.
In the DACH countries it is also a prefix, but I don’t think that applies to all countries. In France, as far as I know, they simply count up at the front depending on the year of registration. Therefore license_plate_code seems suitable. Examples in my area here:
What would be relevant, at least for Germany, is that there are also boundaries with more than one prefix. In the Bodenseekreis, you can choose from three prefixes since the last reform: FN, TT and ÜB. The last two are still the old licence plates which have now been made possible again.
In the U.S., where each state has a separate vehicle registration system, some states still prefix license plate numbers with county codes, but this practice is dying out, so I don’t recall anyone ever suggesting tagging for them. Even in the states that still allocate vehicle registrations by geography, the codes aren’t necessarily a good fit for administrative boundaries. For example, what if two counties share the same overflow code but otherwise use their own codes? What if the prefix indicates a state highway police district, but we don’t map the state highway police districts because they aren’t verifiable?
That said, many states indicate the county on the license plate using a sticker rather than incorporating it into the license plate number. Some states spell out the county name, while others assign an alphabetic or numeric code. Should these codes be tagged similarly to license plate number prefixes? Why not treat them as a kind of ref:*? Some states have parallel systems of county codes, one of which is used by the motor vehicle registrar, another by the highway department, another by the fire department, etc.
After having done some research and browsing Wikipedia articles for vehicle registration plates in various countries I’ve found that area code in some countries it is not a prefix and it appears under different names in different articles. I think sticking to the original vehicle_plate_code is the best choice here.
I’ve also found that in multiple countries different vehicle types or vehicles for important people have different background or text colour. I was also thinking about giving tags to countries that describe the format of the country’s registration plates, however that would just be insanity. I’m sure that a proposal for keys containing full descriptions about vehicle plates would not pass voting because we don’t really need that kind of data in OSM.
Instead I want to stick to the minimum and only have the most important keys which would be registration plate area codes for regular vehicles and eventually for other vehicles such as motorcycles and police cars as well. I created a basic documentation on the wiki which I encourage you to contrubute to by e.g. adding examples and adding onto what I’ve written already since it’s my first post there.