EWIS/ EWS

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.

The FIP.

A Telephone.

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.

A Table.

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 FHR cupboards.  They are designed for the Wardens in each zone have direct communication with the CW in the fire control Room.

 

 

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.

 EWS.

Lets consider a few scenarios

 
A normal working day on level 2 of a multi storey building.

 

 

The alert tone sounds.  The Wardens go directly to the WIPs, everyone else continues working or starts to lock away confidential information.

The CW has arrived at the FIP and located the alarm to level
2 AZ 12 smoke detector 59.  The CW has silenced the alarm by turning the key to manual  on the EWIS (The fire service is on route).  At this time an announcement will be made.
 
The CW has contacted the wardens on leve2  via the WIP and requested them to investigate giving them the exact location of the detector.
The Wardens investigate to discover it is a false alarm (Burning toast from the lunch room).  They return to the WIP and pass the information to the CW.  The fire service arrive the CW briefs the senior attending officer on the status.
The fire service investigate and they confirm that it was a false alarm.  The fire service reset the FIP.
The CW makes an announcement via the PA to inform all occupants that it was a false alarm.
Everyone resumes normal activities.
Scenario Number 2 Fire.
The alert tone sounds.  Wardens make their way directly to the WIPs, everyone else continues
working or starts to lock away confidential information.
The CW has asked the wardens to investigate giving them the exact location of the detector.  When they reach the area they find there is a fire.  Immediatley wardens impliment the evacuation procedures  and contact the CW.
The CW orders the evacuation of the affected floor, 2 above and 1 below.  The fire service arrive and assumes control.