Emergency Warning and Intercommunication System ("EWIS")

An Emergency Warning and Intercommunication System ("EWIS") is a type of warning system used to warn the occupants of a building in the event of a fire or other emergency. These systems are typically designed and installed with respect to Australian Standard AS 1670.4 – Emergency warning and intercom systems, system design, installation and commissioning.

An emergency warning and intercommunication system is typically two systems typically housed in a cabinet. The two components include;

• Emergency Warning System; 
• Intercommunication System.

An emergency warning system comprises control and indicating equipment including one or more amplifiers wired to a series of loudspeakers or visual warning devices distributed throughout the building. The speakers are arranged to that the warning signals (alert and evacuate) are distinctly audible and to ensure that the required A-Weighted prescribed sound pressure level can be achieved.

An intercommunication system is a type of one to one or one to many local telephone system to enable communication between the host (usually the Chief Warden) at the emergency warning system control and indicating equipment ("ewcie") and a remote warden intercom phone.