I was involved in the fire safety aspects of a new apartment block of 3 storeys. At a meeting of minds I queried the "required" installation of a common fire alarm system. This requirement came from BC as the IO "liked to see one installed". I questioned the installation and suggested the developer go back to BC to seek clarification and confirmation on this and, if BC insisted by liking one installed, a detailed assessment as to why and to what category.
Despite this the installation went in.
10 miles down the road, in another council area, BC there seem to have read the books and don't require common systems in purpose built apartments.
So perhaps BC might be able to shed light on why MCPs are installed in apartments never mind in common areas.