[Tagging] Inaccurate and incomplete parking:lane/parking:condition definitions

[Minh Nguyen]

The parking:lane=* documentation [1] says parking:lane:*=* can be set to 
either a position or a prohibition, while parking:condition:*=* can be 
set to either a condition or a prohibition. The page defines the 
following prohibition values based on Vienna Convention signs 
(specifically German signs):

* no_parking -- "parking" is disallowed, but pickups and dropoffs are 
allowed
* no_stopping -- "stopping" is disallowed except for e.g., a red light
* fire_lane -- same as no_stopping but stricter due to use by emergency 
vehicles

It also documents the following equivalences to terminology on U.S. 
parking signs:

* Loading Zone means no_parking
* No Parking means no_stopping
* Nothing about No Stopping

This always struck me as a counterintuitive correspondence unlikely to 
be mapped correctly. Just to be sure, I compiled a table listing the 
specific driver actions that are allowed and disallowed by each sign in 
Germany and the U.S. based on the definitions on the wiki. [2]

Based on the table, I believe the documented equivalences are 
inaccurate: no_parking means No Parking and no_stopping means No 
Stopping. But I would appreciate it if someone more familiar with 
parking regulations in Germany or elsewhere in Europe could review the 
table for inaccuracies.

One thing that becomes clear is that the documented tagging scheme is 
far too simplistic. For one thing, it treats fire lanes as mutually 
exclusive to stopping prohibitions. However, by the wiki's own 
admission, they're the same, just carrying different penalties. 
Meanwhile, in the U.S., either No Parking or No Stopping can be due to a 
fire lane for a variety of other reasons.

I think parking:condition:*=fire_lane should be replaced by 
parking:condition:*=no_stopping plus parking:condition:reason=fire_lane. 
parking:condition:*:reason is already in very common use, but not that 
particular value, probably because of the existing parking:condition value.

Another shortcoming is the lack of an affordance prohibiting what 
American laws call "standing": stopping to pick up or drop off a 
passenger, potentially putting the vehicle in the Park position and 
exiting to open the passenger door or help the passenger with their 
belongings. Loading and unloading goods is disallowed. This is such a 
common sign in U.S. cities that I think there should be a convenient way 
to tag it. Would no_standing be appropriate, or does British English 
have a corresponding term for this distinction? (Sometimes there are 
additional nuances like school passenger loading only or cargo loading 
only. However, those nuances could be captured in subkeys or conditional 
tagging.)

Finally, there's no provision for the "no idling" signs sometimes found 
in the U.S. and apparently some parts of Europe as well. [3] These signs 
require you to turn off the engine but don't affect how long the vehicle 
can remain at the curbside. They're typically installed for 
environmental protection or nuisance abatement.

[1] https://wiki.openstreetmap.org/wiki/Special:PermanentLink/2179892
[2] 
https://wiki.openstreetmap.org/wiki/Talk:Key:parking:lane#Parking.2C_stopping.2C_and_standing
[3] https://commons.wikimedia.org/wiki/Category:No_idling_signs

-- 
minh at nguyen.cincinnati.oh.us