39
Arrangement of smoke detectors in special spatial geo-
metries
Stairwells require at least one smoke detector mounted in the upmost
level. It is recommended to mount a smoke detector on every level.
Landings and galleries with a width of more than 2 m and an area larger
than 16m² require also the mounting of a smoke detector.
If the ceiling is divided by wooden rafters or ceiling compartments,
please observe the following:
Rafters or compartments with a depth of less than 20 cm can be
neglected. The smoke detector can be mounted in the middle of the
room either within a compartment or on a rafter.
If the rafters or ceiling compartments are deeper than 20 cm, the total
area of the ceiling compartments defines the mounting location. If the
total area of ceiling compartments exceeds 36 m², a smoke detector is
required in the middle of every compartment.
If the total area of ceiling compartments is equal or smaller than 36 m²,
the smoke detector can be mounted in the middle of the room either
within a compartment or on a rafter.
