Some I ago, I raised a proposal for Marine Rescue stations: Proposed features/Marine rescue - OpenStreetMap Wiki. After a few weeks, I returned it to draft status, pending the resolution of the Military Bases proposal which was also going through at that time, but despite that, it’s now in use ~250 times!
One of the concerns that were raised at the time was the existence of two other, similar tags: emergency=lifeboat_station Tag:emergency=lifeboat_station - OpenStreetMap Wiki & also amenity=lifeboat_station https://wiki.openstreetmap.org/wiki/Tag:amenity%3Dlifeboat_station, both of which were created by the same mapper on the same day, & neither of which were apparently ever discussed?
These two tags have been used a similar number of times (400 – 450), but when I’ve looked at a number of them at random, both tags have been used together on a lot of locations e.g Way: Harwich Lifeboat Station (260096274) | OpenStreetMap, Way: Walton and Frinton Lifeboat Station (894864797) | OpenStreetMap, & Way: West Mersea Lifeboat Station (444884651) | OpenStreetMap.
It would seem somewhat ridiculous to have three virtually identical tags describing the same thing, so I am suggesting that they all be consolidated into one tag, with the other two being deprecated.
Before proceeding with that discussion though, is there any reason to tag something as both an amenity= & also emergency=?
Also raised on Tagging list for discussion.