Smoke alarms can warn of fires as early as the development phase and make a decisive contribution to the survival of people. They trigger when there is an increased concentration of carbon monoxide (CO), carbon dioxide (CO2) or other combustion gases. A visible fire does not necessarily have to result from flames. A smoldering fire with its gases already causes a considerable health risk.
Smoke alarms are particularly intended to wake sleeping people in order to bring themselves and other people to safety at an early stage.