Emergency and hazard intercom systems (Notfall- und Gefahren-Sprechanlagen, NGS) are used for immediate emergency and danger alert, verification by voice communication, warning of a hazard, immediate notification of responsible authorities/rescues teams and communication of codes of behaviour. The prerequisite for an appropriate approach is a previous risk assessment and the definition of protection goals in accordance with DIN VDE V 0827-1 (VDE V 0827-1).