An Emergency Warning and Intercommunication System (EWIS) is a building-wide system that provides emergency warnings and enables communication between the building’s emergency control personnel during an evacuation. An EWIS incorporates emergency warning and intercommunication functions and is designed and installed in accordance with the applicable Australian Standards and building requirements, including AS 1670.4 where applicable. You will find an EWIS in larger or more complex buildings, where a single all-at-once alarm would create dangerous crowding in the stairwells.

What an EWIS is made of

An EWIS is really two connected systems working as one:

• Emergency warning system. A master emergency control panel, amplifiers, loudspeakers and visual warning devices that broadcast alarm signals and voice messages across the building, zone by zone.
• Emergency intercom system. Dedicated phone points, known as Warden Intercommunication Points (WIPs), that let the Chief Warden at the control panel speak directly with floor and area wardens in each zone.

Together, these two parts let one person coordinate a whole building in real time, instead of sounding one alarm and hoping occupants work out the rest for themselves.

How an EWIS works in an emergency

In a typical activation:

1. Detection. A fire detection or alarm device, sprinkler system interface or manual alarm point may initiate the alarm sequence, depending on the building’s system configuration.
2. Warning. The EWIS sounds the alert signal, which indicates that an emergency response is underway and that occupants should listen for further instructions. The evacuation signal indicates that occupants should evacuate in accordance with the building’s emergency procedures.
3. Coordination. The Chief Warden takes manual control at the panel and uses the WIPs to direct wardens, confirm each area is clear and decide on a full or partial evacuation.
4. Staged evacuation. Because the building is split into zones, an EWIS can move the most at-risk floors first and hold the rest, keeping stairwells clear and the evacuation orderly.
5. Alert signal vs evacuation signal. An EWIS uses two distinct signals. The alert signal tells occupants to stop, pay attention and prepare. The evacuation signal, the rising whoop, means leave now by the nearest safe exit. Knowing the difference is a core part of warden training.

Which buildings need an EWIS?

An EWIS is generally required in larger or higher-risk buildings, such as high-rise offices, hospitals, shopping centres and aged care facilities, based on the building’s classification under the National Construction Code. Smaller or lower-risk buildings often use a simpler occupant warning system that only sounds an alarm. What sets an EWIS apart is the intercommunication layer, the ability for wardens to talk zone to zone and stage the evacuation, which is why it is reserved for larger and more complex sites. Once installed, it must be routinely tested and maintained under AS 1851. Because requirements depend on your building’s classification and fire safety design, confirm your obligations for your specific site.

Where the EWIS fits in your emergency plan

An EWIS is only as effective as the people using it. Under AS 3745, your Emergency Control Organisation must be trained to operate the panel, the WIPs and the warning signals, and to fold them into your emergency response procedures. If your team is not confident using your building’s system, that is a gap worth closing before it is tested for real.

Frequently asked questions

What does EWIS stand for?

EWIS stands for Emergency Warning and Intercommunication System.

Is an EWIS the same as a fire alarm?

No. A fire alarm detects and signals a fire, while an EWIS adds a warden intercom and staged, zone-by-zone evacuation control.

Who operates an EWIS during an emergency?

The Chief Warden takes manual control at the panel and directs wardens through the Warden Intercommunication Points.

First 5 Minutes helps Australian facilities build compliant emergency plans and train wardens to use their building’s systems with confidence. Explore our AS 3745 Compliance Essentials and fire warden training, or get in touch to talk through your site.