2.2 Selecting Alarm Type
1Optical Smoke Alarms are recommended due to their excellent response
to smouldering fires. If there is likely to be problems with steam,
contamination or dust build-up, or if there is significant risk of a fast burning
clean fire an Ionisation Smoke Alarm should be fitted.
2Some Fire Authorities recommend that both Ionisation and Optical
Smoke Alarms should be fitted for the fastest response to all types of fires.
3Some Fire authorities (concerned with the slow response of Heat Alarms)
advise that Smoke Alarms should be fitted.This is acceptable according to
BS 5839-6 provided there are clearly not going to be problems with
nuisance alarms. Fit Heat Alarms only if nuisance alarms are very likely
and it is acceptable that a warning will only be given by the Heat Alarm
when there is a very significant flaming fire in the room.If the door(s) and
windows are not closed to contain the fire and heat, it is extremely unlikely
that the Heat Alarm would respond before a Smoke Alarm sited outside in
the corridor.
4In enclosed kitchens with doors closed.
5Greatly depends on ventilation and distance from source of fumes.
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Locations
Hall, Corridors, Escape Routes

Alarm Type

Optical Ionisation Heat
Bedrooms
Shower / Bathroom
Kitchens
Living Rooms
Fire Response
Slow Smouldering Fires
(polyurethane foam, ignited bedding etc.)
Nuisance Alarm Immunity
Cooking Fumes
Steam, Condensation &
Dust Build-up
Fast Flaming Fires
(chip pans, flaming wood/plastic, oil,
solvents etc.)
- Best - Good - Acceptable - Not Suitable
Temperature >580C
(only in areas with cooking fumes, steam,
very dirty/dusty)
Optical/Ionisation/Heat Alarm Selection

Locations & Performance

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