[Tagging] access agricultural, WAS Re: Reviving the conditions debate

[Martin Koppenhoefer]

2012/6/14 Philip Barnes <phil at trigpoint.me.uk>:
> The other usage of the term agricultural is the type of vehicle.
>
> In the UK agricultural vehicles are prohibited on motorways due to their
> slow speeds. But a farmer could use his Land Rover on a motorway as it is a
> car being used for agriculture.


Yes, unfortunately instead of discussing the issue there was repeated
wiki fiddling on this issue. I tried to dig into this and am
presenting the results here:
agricultural was introduced 25 Dec. 2007, but without further definition:
http://wiki.openstreetmap.org/w/index.php?title=Key%3Aaccess&action=historysubmit&diff=66244&oldid=14009

on 4 Feb. 2009 there was a definition added: *
{{Tag|access|agricultural}} ''Only for agricultural traffic.''
http://wiki.openstreetmap.org/w/index.php?title=Key:access&diff=next&oldid=218932

(this might have been intended as a use condition, because otherwise
it would have been "agricultural vehicle", but actually the wiki was
still not very clear, because in the following time it listed use
classes (hazmat, emergency, hov) together with vehicle classes
(motor_vehicle, hgv). This is also reflected by the diagram that was
added on 23 Feb. 2009:
http://wiki.openstreetmap.org/w/index.php?title=Key:access&diff=prev&oldid=231676
and amended on 11 March 2009:
http://wiki.openstreetmap.org/w/images/e/e9/Access_modes.png

on 20 Aug 2009 there was a contradiction introduced, agricultural was
still defined as agricultural traffic but the same time lower in the
page there was added this (still there was no distinction between use
cases (hazmat, emergency) and vehicle types): agricultural=*
(agricultural motor vehicles, e.g. tractors, that have additional
restrictions, e.g. a 25km/h speed limit). The diagram was replaced.

5 days later this was relativated by separating "by use" and vehicle
classes, keeping the class definition for agricultural in parenthesis
though:
http://wiki.openstreetmap.org/w/index.php?title=Key:access&diff=prev&oldid=327300

This situation was kept until 5 Jan 2012, when "agricultural" was
moved from "by use" to "double tracked vehicles".
http://wiki.openstreetmap.org/w/index.php?title=Key%3Aaccess&action=historysubmit&diff=720329&oldid=720323
Which is where we are now. The beginning of the page still states that
agricultural is a tag for agricultural traffic.

How can we resolve this? It seems obvious that we need either 2 tags
for agricultural (according to the legislation, either a vehicle class
or a use case is intended), or we accept that the same tag has
different meanings in different legislations/countries. Personally I
am in favour of an additional tag. We could also have 2 new tags:
"agricultural_use" and "agricultural_vehicle" to make it unambiguous,
and to deprecate the unclear agricultural.

What do you think?

cheers,
Martin