Fire alarm detector types.
The detector in the right place matters more than the number of detectors. This is what each type senses and where it belongs.
The main types
| Detector | What it senses | Typically used in | Not ideal for |
|---|---|---|---|
| Optical smoke | Smoke particles scattering light | Corridors, offices, bedrooms, general areas | Steamy or dusty areas |
| Heat | A fixed temperature or fast rise in temperature | Kitchens, boiler rooms, garages, dusty places | Early warning of slow, smouldering fires |
| Multi-sensor | Smoke and heat combined | Areas that need early warning but suffer false alarms | Where a plain heat detector is enough |
| Beam | Smoke crossing a beam over a large space | Atria, warehouses, large halls | Small rooms |
| Carbon monoxide | Carbon monoxide gas | Rooms with fuel-burning appliances | Fire detection. It is a separate safety device |
Placement matters
Detectors are positioned according to the standard that applies: spacing, distance from walls and obstructions, ceiling height and airflow all matter. A smoke detector too close to a kitchen will cause unwanted alarms; a heat detector in a corridor will detect a fire later than it needs to. Good installation is largely good siting.
Kitchens and unwanted alarms
Cooking fumes and steam are the commonest cause of false alarms. The usual solution is not to remove detection but to use the right type, a heat detector or a multi-sensor, in the right place. See false alarms.
Maintenance
Detectors collect dust, insects and grease and need periodic testing and cleaning as part of servicing.
Common questions.
What is the difference between a smoke and a heat detector?
A smoke detector responds to smoke particles and gives the earliest warning in most areas. A heat detector responds to temperature and is used where smoke detectors would cause false alarms, such as kitchens.
Do I need carbon monoxide detection as well?
Carbon monoxide alarms warn of gas from fuel-burning appliances and are separate from fire detection. They are needed in some properties and recommended in others.
Can I move or remove a detector myself?
No. Detector positions are part of the design. Covering, moving or removing them can compromise the system and, in a business, the legal arrangements.
Speak to a fire engineer.
Call, message or send the form. We reply the same working day wherever we can.
