Alarm Sensor Types
Which alarm sensor goes where?
Fire alarms have different sensors to detect different fire types. Some alarm sensors react to heat and some to the physical smoke created by a fire. By fitting the right type of alarm sensor you will avoid nuisance alarms and get the best protection.
Here is our guide to choosing the right types of alarm system for each area within a property. The two houses below show rooms that are colour coded to show which sensor types are best suited to each area of a typical property.
Layout using Multi-Sensor fire alarms:

Layout using single sensor fire alarms:

Multi-Sensor Alarm
Responds to all fire types from fast flaming to slow smouldering, providing the best fire response.
Multi-sensor alarms contain both an optical and heat sensor to detect both smoke and heat. As the alarm intelligently monitors both sensors, the risk of nuisance alarms is virtually eliminated.
Multi-Sensor Alarms should be installed in the Hallway, Landing, Living Room, Dining Room and Bedrooms.
We recommend the Mains Powered Multi-Sensor Fire Alarm – Ei3024
Optical Sensors
Detects smoke from slow, smouldering fires such as electrical fires
Alarms containing optical sensors use an infra-red beam to detect smoke and are less prone to false alarms from cooking fumes if fitted in the hallway next to kitchens.
Optical Alarms should be installed in the Hallway, Landing, Living Room, and Dining Room
We recommend the Mains Powered Optical Smoke Alarm – Ei3016
Heat Sensors
Detects changes in temperature using a thermistor
Alarms containing heat sensors only detect changes in temperature using a thermistor. The trigger level is set to 58°C degrees. Ideal for kitchens as they will not create nuisance alarms from cooking fumes, but should not be used in other areas of a property as they will not provide the speed of response required – smoke alarms should be used instead, see above for guidance.
Heat Alarms should be installed in the Kitchen and Garage.
We recommend the Mains Powered Heat Alarm – Ei3014
Interconnected Alarm Systems
Interconnect your alarms for full audibility
Regardless of the house alarm type, alarms should be interconnected throughout a property to ensure all alarms sound in the event of an activation, providing audibility for the occupants. By using RadioLINK, alarms can be interconnected wirelessly using Radio Frequency signals to reduce the time and disruption from running cabling between the alarms.
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