Emergency Warning and Intercommunication System (EWIS) (Ref BCA E4.9, MS 76 Schedule 3.8, AS 1670, AS 2220, AS3745, AS 1851 and AS4428). These systems are installed in buildings over 25 m in height and work in conjunction with the FIP in a Fire Control Room (FCR) (Ref BCA E1.8, MS SA 76 Schedule 3.5). A FCR must be accessible via two paths of travel, one from the front entrance of the building and one from a public place or fire isolated passageway that has a fire door fitted with an FRL of not less than -/120/30. A FCR must have a floor area of not less than 10m2 and they must contain the following.
A Blackboard or Whiteboard of not less than 1,200mm x 1,000mm.
A Pin board of not less than 1,200mm x 1,000mm.
Colour coded fire plans.
(See BCA and the AS for further information).
EWIS systems are designed to enable the Emergency Control Organisation (ECO) to locate the cause of the alarm so to prevent a premature evacuation during a false alarm. The EWIS systems can also be used to assist in an orderly evacuation of a building in the event of an emergency. The EWIS can be initiated by 1 of 3 ways. Automatically by a detector, so activating the fire alarm system, by a building occupant breaking a Manual call point or by the Chief Warden (CW) manually at the EWIS panel (simply by turning the key to manual). There is not necessarily the need for a CW as the EWIS will automaticly evacuate the building after a set time, for example 2 minutes. The regular test shall be carried out by the ECO members at weekly, fortnightly or monthly intervals, or as determined by the Emergency Planning Committee (EPC). (Ref AS 3745).
EWIS systems comprise of, but not restricted to of some of the following:
Public Address (PA). This is operated by the CW who can either address the whole building or individual zones. Green Buttons.
Warden Intercommunication Points (WIPs). These are the red phone /s in each area normally located adjacent to exits or in
Alert Tone “Bleep Bleep.” When this tone sounds it doesn’t necessarily mean there is a major problem in the building. When the alert tone is heard the ECO put into place their emergency procedures for the building. The CW would assume control at the fire control room / FIP, the wardens pick up the WIPs in their zones and await instructions from the CW. The CW can also alert individual zones manually. Amber buttons.
Evacuation Tone “Whoop Whoop.” All occupants should vacate the building via the closest or safest emergency exit and not use the lifts. The CW can also evacuate individual zones manually. Red buttons.
Lets consider a few scenarios
The alert tone sounds. The Wardens go directly to the WIPs, everyone else continues working or starts to lock away confidential information.