JOHAN broadcasts common notifications and warning signals (Default warning announcements and signals recorded in the internal memory) both in interior and exterior areas on the basis of the following:
- Direct input from a microphone, or from a local control module;
- Instructions from a supervisory computer via VEKTRA control software;
- Automatic triggering by external inputs – data from various sensors, buttons;
- Direct input from other communication systems – mobile phones, fixed phone lines, radio stations, VHF radio, satellite communication systems etc.;
The system meets the requirements of the STN EN 60849 standard related to emergency acoustic systems and it is equipped with battery back-up as standard equipment.