The Civilian Hospital is a tech building in Tiberian Sun.
In Tiberian Sun, in contrast with Red Alert 2, Civilian Hospital is a civilian building which cannot be captured. However in the rules.ini file which is essential part of the game there is the next line in the "Unit Statistics" part: "Hospital = Can this building heal infantry (def = no) ?" In the same file there are the following lines in the definition of Civilian Hospital: "Use Ammo to specify the number of times to allow healing." and "Hospital=yes".
Together these suggest that even in Tiberian Sun its use as a hospital was planned, but for some reason this was discarded in the end.
Without modifications, Civilian Hospital is a civilian building which is neutral and cannot be used for any purposes. However, by changing the rules.ini file to enable its capture, it become a fully functional hospital which heals the infantry sent to it. Healing capacity of the Civilian Hospital is determined by the Ammo parameter as the rules.ini suggests, and can be changed by overwrite the original value. Similar to Red Alert 2, infantry could be sent to hospital only one by one. The Nod campaign mission Escort The Bio-toxin Trucks features a player-owned hospital which can be used to quickly heal your Cyborg Commando.
It should be noted that they can only be killed by super weapons, or direct fire.