Thanks for the replies, its clear to me that a "Flats & Common Areas" guide is sadly lacking in this type of premises. Why not go for AFD in the common areas and stairwells and leave it to the individual to protect his/her own apartmet through choice; and at least give early warning of a fire in a neighbouring flat when smoke issues through the entrance door....and most of all make it retrospective. Its the common areas that need protecting as in certain circumstances, if travel distance is okay and lobbies are provided in the flat or at the stair entance, it is the only MoE and could be compromised.
If a flat entrance door & lobby function well, a fire could remain undected for hours, (sorry to say this but you can "right-off" persons in the room of origin, but once it has spread beyond the room of origin, the fire is somewhat hungry for fuel. A typical smoke-in-bed fire during the early hours of the morning could manifest itself for some time and when overcoming the front door, prevent or hinder escape for other residents.
In perspective, airbags in cars save lives, a 1990 Ford Escort cant be made retrospective to fit them, new cars do. But in a 1990 Escort if your airbag is non-existent because it aint fitted, you are not affecting the other "as new fitted air bag" road users' life.
On another note its worth remebering that AFD will detect but not extinguish or contain an outbreak of fire, how about going the extra mile and make resi-sprinklers also retrospective in flats as well, wow how radical is that! Letting & Management Agencies are comparitively easy bodies to hold accountable with regards protecting the common MoE to, as opposed to dictating an AFD requirement within individual residents households.
Why leave a grey area grey? (PS is that "grey" or "gray" I could never grasp that concept at school - answers on a postcard to.........)