diameter=* in combination with man_made=pipeline refers to the NOMINAL diameter of the pipe, that is related but not equal to the inner diameter. It is documented on pipeline and diameter wiki pages.

In case of fire_hydrant:diameter it is again the NOMINAL diameter of the hydrant, that is often printed on it and it refers to the flanged connection to the underground pipeline. Again it is documented on hydrant wiki page.

Anyway I gave up on changing that tag, it will reamain as it was before, for better or for worse. We need to go on with the other new tags, so please see the new proposal here:

osm.wiki/Proposed_features/Fire_Hydrant_Extensions_(part_2)

I and all the people that worked on the proposal would like any comments to come out BEFORE the beginning of the vote.

Thank you

Alberto

@kucai what do you mean?

@ escada Well, for me it will not be a pain to retag my hydrants, if it brings to a more logical structure. And with overpass it’s quite easy. I am spending more time trying to explain our reasons than it would take to retag all 400.000 fire_hydrants:diameters=* all over the world.

@Nakaner We can go on splitting and splitting, but I suspect we will go in a neverending story and I’m loosing confidence in the voting process. Instead of simply voting no, why don’t you help us with further improvements? Some things can be adjusted or explained better in the final wiki page, but you can’t wait in silence that we do all the hard discussion work and then jump out only to the vote and expect that we rewrite all because it doesn’t match your standards. Please be cooperative, not obstructive.

About the namespace, even you admit that there are reasons for removing them. In this case there is not the problem of having on a hydrant node another feature that requires diameter, pressure, or location. A hydrant should have a node for itself only.

Why should we continue to use fire_hydrant;pressure, if pressure already exists and it’s simpler? Tomorrow when pressure will have its own detalied wiki page, someone can read it and use it on hydrants. The same with diameter and location. So in future we will have some hydrants with namespace, and others without it.

Instead if we do now the simplification, tomorrow all hydrants will have homogenous and simpler tags. In the long term, simple is better, and for me this is a good reason to change all 400.000 recurrencies, obviously allowing a transition period when old and new tags coexist, to allow software adjustements.