By the SightShield team · · 3 min read
Detect early, without false alarms
The best detector for a room is the one that responds early to a real fire there without being triggered by normal activity. That is why most buildings use a mix of detector types.
The main detector types
| Type | How it works | Best for | Avoid in |
|---|---|---|---|
| Optical (photoelectric) smoke | Smoke particles scatter light inside a chamber | Offices, bedrooms, corridors, stores, server rooms | Kitchens, dusty or steamy areas |
| Fixed-temperature heat | Operates at a set temperature | Kitchens, boiler rooms, generator rooms | Areas needing early warning |
| Rate-of-rise heat | Operates when temperature climbs quickly | Workshops, car parks, plant rooms | Places with normal fast heat changes |
| Multi-sensor | Combines smoke and heat sensing | Mixed-use rooms, hotel rooms, offices | — |
| Beam detector | Smoke blocks a light beam across a large space | Warehouses, atriums, factory halls | Areas with obstructions |
| Flame (UV/IR) | Detects flame radiation | Fuel stores, special risks | General areas |
Room-by-room guide
| Area | Usual choice | Why |
|---|---|---|
| Offices, cabins, corridors | Optical smoke | Early warning of smouldering fires |
| Kitchens and pantries | Heat (fixed or rate-of-rise) | Cooking smoke and steam cause false alarms in smoke detectors |
| Server and electrical rooms | Smoke, often multi-sensor; aspirating systems in critical rooms | Electrical fires smoulder before flames |
| Basement car parks | Heat, or multi-sensor | Vehicle exhaust and dust |
| Warehouses with high ceilings | Beam detectors or aspirating systems | Point detectors are hard to reach and slow at height |
| Hotel rooms | Smoke, with care near bathrooms | Sleeping occupants need early warning |
| Generator rooms | Heat | Exhaust and heat in normal operation |
Avoiding false alarms
- Use heat detectors in kitchens, pantries with toasters and areas with steam.
- Keep smoke detectors away from AC vents, bathrooms and dusty process areas.
- Cover detectors during construction or painting work, and uncover them after.
- Clean and test detectors regularly — dust in the chamber causes false alarms.
- Use multi-sensor detectors where conditions vary.
Placement basics
- Mount point detectors on the ceiling, where smoke and heat collect, not on walls unless designed for it.
- Keep clear of AC diffusers and fans that blow smoke away from the detector.
- Mind beams, ducts and deep false-ceiling cavities, which can need their own detectors.
- High ceilings and sloped roofs change spacing; follow the design code rather than a rule of thumb.
- Do not paint detectors or cover them with decorations.
Standards and certification
In India, IS 2189 is the code of practice for selecting, installing and maintaining automatic fire detection systems; its fifth revision, IS 2189:2026, was published in 2026. Smoke detectors are covered by IS 11360 and are listed by BIS under mandatory certification. Ask your installer to design to the current code and to use certified detectors.
Fire alarm design and installation →Standalone smoke alarms for homes
Homes and small flats often use standalone battery smoke alarms rather than a full fire alarm system. They detect smoke and sound a loud alarm themselves, with no panel. Choose models with a long-life sealed battery, put one in the hallway outside bedrooms and one in the living area, avoid the kitchen, and test them monthly with the test button. Interlinked alarms — where one sounding sets off all of them — are better in villas with several floors.
Fire Alarm Systems for Apartments →Quick answers
Should a kitchen have a smoke or heat detector?+
A heat detector. Smoke detectors in kitchens cause frequent false alarms from cooking.
Which detector is best for a warehouse?+
Large open warehouses often use beam detectors or appropriately spaced smoke detectors, depending on ceiling height and layout.
Do smoke detectors need BIS certification in India?+
Smoke detectors to IS 11360 are listed by BIS under mandatory certification. Use certified products.
Why does my smoke detector go off when nothing is burning?+
Dust in the chamber, steam, cooking fumes, insects or AC airflow are the usual causes. Clean the detector, check its location, or replace it with a heat or multi-sensor type where conditions demand.
How often should detectors be tested?+
Test systems on a regular schedule set by the maintenance plan, typically with a portion of detectors tested at each visit so every detector is covered over the year, and clean them as needed.