Fire detection in lift lobby ?

[kurnal]

We must remember that most service risers are protected shafts with fire resisting doors provided with smoke seals.

Lift shafts are a little different as these are the only fire doors in Approved Document B not required to have smoke seals- this is always imossible to achieve in a sliding door.

[Benzerari]

Also most risers I have seen have detectors inside in each floor, while in lift shaft has only one in the top...

[Big_Fella]

What if you have an open riser going through several floors.  A detector would be mounted at the top.  Would it be required to have a detector also outside the riser as you would a lift?  Or am I missing the point?

[Wiz]

What if you have an open riser going through several floors.  A detector would be mounted at the top.  Would it be required to have a detector also outside the riser as you would a lift?  Or am I missing the point?

As I previously advised, yes it would. Any flue-like structure penetrating through floors requires it - smoke sealed doors or not! (just in case the door was left open or the seals didn't work?). BS 5839 part 1 2002 22.2.C) refers.

Please note that the detector needs to be on the 'accommodation' side and not in the flue-like structure (apart from the one at the top of the flue-like structure, of course) and you only need it IF the accommodation side of the flue-like structure is an area that would require detection anyway by virtue of the system category designation.