The Gira wireless smoke detector is part of the Gira wireless alarm system/VdS. It is in constant wireless contact with the Gira wireless alarm control unit/VdS and sounds the alarm before the smoke concentration becomes hazardous to people, also locally via an integrated buzzer. The smoke detector detects fire at an early stage through the build-up of smoke. It operates on the basis of the photoelectric scattered light principle. The smoke analysis function is continuously monitored.