Your probably here after searching for Street Furniture! The concept of street furniture has been implemented in a number of different way within OpenStreetMap. Below is a list of "Furnitures" and their associated, agreed upon, tagging pages.
- Speed Bump is already approved as traffic_calming=bump
- Gate is already approved as barrier=gate
- Barriers are implimented as barrier=*
- Bollards are already approved as barrier=bollard
- Parking Meters should rather be amenity=parking with fee=yes
- Seats and Benches are under vote at amenity=bench
- Fire Hydrants are suggested, see Proposed features/Fire Hydrant