Mains or battery-powered smoke and heat detectors are sensor-based devices placed within a property to detect smoke or heat. Once detected, a loud audible alarm is emitted from the device.

Fire alarm systems, on the other hand, are the complete package when it comes to fire safety. While they include both smoke and heat detectors, fire alarm systems have the added capability of alerting people across an entire premises via an alarm and/or flashing warning lights, triggering sprinkler systems and emergency lighting, and can be monitored by alarm receiving centres (ARCs).