False alarm ratio of fire detection and fire alarm systems in Germany – A meta analysis

False alarms are – in terms of fire safety engineering – fire alarms in absence of a real fire condition. They are related to the exchange of information and occur as a side effect of system technologies and the alerting process. Fires often are associated with considerable damages. Because time is a critical factor, detection is often accomplished by installed Fire Detection and Fire Alarm Systems (FDAS). The highly sensitive sensors in fire detectors make the identification of fires in an early stage possible, but this also makes FDAS susceptible to false alarms. So far there is no reliable evidence on the ratio of false alarms to installed FDAS. The studies, which are described in the present paper, close this gap for Germany on the basis of an empirical analysis of data from fire brigades. This meta-analysis show that today the false alarm ratio triggered by installed FDAS (and connected to a fire brigade) is high in Germany. It is difficult to describe the ratio in one single value, because a great number of conditions and influencing factors are relevant. To reduce the false alarm ratio, we need a common understanding of false alarms and a consistent use of terms and categories.