/ FIRE INDICATOR PANEL
The SSIS system goes into operation following an alarm being processed by the fire indicator panel (FIP). The fire indicator panel provides an output to identify the affected level / zone in the building to the master evacuation control panel (M.E.C.P). The system functions to produce general alert and evacuation tones as required for individual evacuation zones in the building. The alert tone is required to time out and be replaced by the evacuation tone. The code specifies the frequency profile for the tones.
In most multi-storey buildings, except for carparks, each storey will be an evacuation zone as each storey is a different fire compartment under the BCA. A carpark is usually a single fire compartment as each carpark level is connected by vehicle ramps therefore it is permitted to function as a single zone. A typical installation will also incorporate a verbal address facility, preset spoken message response, system status and faults and has a dedicated battery backup power supply.
/ EMERGENCY CONTROL ORGANISATION
In multi-storey buildings, the SSIS can only function to its optimum when an Emergency Control Organisation (ECO) is effective with duties of chief warden and wardens being allocated. These persons must be correctly trained and regular evacuation drills need to be conducted. AS 1670.4 requires automatic execution of a building evacuation alarm and the alert signal set to “0” seconds in time unless the emergency planning for the building has considered and specified a longer period. Depending on the actual fire circumstances, the SSIS systems installed in a multi storey building may continue to go into alarm for zones above the initial fire affected floor. This means that zone priorities will move according to the zones going into alarm, as registered at the fire indicator panel, and as the master evacuation control panel automatically responds to the signals received from the fire indicator panel. The alarm priority to other zones or levels in the building can also be controlled by the chief warden or fire brigade through SSIS as circumstances require, hence the importance to integrate an ECO into the building.
It is worth noting that AS 1670.4 is not very specific as to the sequence of alarm to zones or levels so a logical system would have an override function to allow the chief warden to manage total building evacuation in a timely manner. It is possible that total evacuation of the building will not need to occur if the initial alarm and fire is isolated to its point of origin.