@flo I did read the details. The details didn’t say anything about actual speakers (I am an actual speaker, by the way, just not a native speaker). If you wanted to poll only native speakers from different countries without referring to any online sources at all, you should have said so (“Google Translation etc.” does not clearly exclude all online sources whatsoever, if that’s what you meant; I took it to mean strictly language references like translators and dictionaries).
Anyway, I answered your question. Extincteur (sometimes adding de feu or d’incendie) is apparently used throughout the French-speaking world, and the various words for “fire hydrant” in different countries are there in bold in the first paragraph of the second item I linked.