When designing a fire alarm system in accordance with the standards, the floor area of a single zone should not exceed 2 000 m2. However, in the case of a zone comprising mainly a single, open plan area (e.g. an uncompartmented warehouse), which should not exceed 10 000 m2 in area.
Additional recommendations applicable to detection zones that contain non-addressable automatic fire detectors.
The following recommendations are applicable.
a) The floor area of a single fire detection zone of a fire alarm should not exceed 2 000 m2.
b) The search distance (the distance that has to be travelled by anyone responding to a fire alarm signal after entry to the zone in order for the location of the fire to be determined visually, see 3.50) should not exceed 60 m.
Having entered the fire detection zone, the person responding to the alarm signal need not reach the seat of the fire within the
recommended search distance; it is only necessary to become aware of the location of the fire.
In measuring search distance, the worst case, in which the fire is located at the furthest concealed area from any likely
point of entry to the zone, should be considered (see Figure 2).
c) fire alarm automatic fire detectors within any enclosed stairwell, liftwell or other enclosed flue-like structure
should be considered as a separate #detection zone. Manual call points located at final exits to open air
from stairwells may be incorporated within these detection zones [but may, alternatively, be
incorporated within the detection zone described in 13.2.1a)].
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