I am not implying this is the case in the hospital fire to which you refer, but when you talk about compartments and sub compartments it must do what is says on the tin, i.e. 30 min FR or 60 FR. Look at the things that breach a wall or door, electric sockets back to back, a 45 mm door with a lock in it that takes up 40 mm of the width. Of course you need them but you must reinstate the integrity, intumescent paper round the lock, hinges etc and intumescent gaskets in sockets. A lock that drops out of a door in six minutes throws your fire strategy to pot. All these things can lead to unexpected fire spread; there are still contractors and others that have never heared of these things, so we need to make sure they are in place.