User Manual

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4.2.4 Alerting the municipal fire service
The municipal fire department may be alerted in one of
two ways:
 Automatically via the fire detection system by remote
transmission
 Manually by telephone
There are a number of advantages of notifying the fire
service automatically:
 The building is protected even when unoccupied
(night-time, weekend etc.)
 No risk of human failure due to unclear assignment
of responsibility
 Unaffected by stress in emergency situations
 The notification of the fire service is automatically
recorded by the fire protection system
Note that in certain regions the initial alarm may be
transmitted to an Alarm Receiving Center (ARC) which,
in turn, will notify the local fire department.
4.2.5 Alarm strategies
General alarm
A general alarm is a defined audible signal which is
sounded throughout the building. The alarm is
automatically activated by the fire detection system,
or manually from the security manager’s office. In the
majority of education facilities this should trigger the
immediate and total evacuation of the building.
Staff alarm
When the first signs of an incipient fire are detected, only
members of staff are initially informed. This gives the
designated staff members a short period of time to
investigate the cause of the alarm and deal with any
incipient fire. If the fire cannot be dealt with within the
specified timeframe, then the staff are responsible for an
orderly evacuation procedure in accordance with
evacuation plans that have been practiced regularly. The
staff alarm function is based on the standard Alarm
Verification Concept (AVC), which is described in detail
in the following section.
Staged alarms
Staged alarms are based on systems capable of
generating an ‘alert signal’ and a different ‘evacuate
signal’. However, such systems are not generally
applicable in the education sector. Although staff can be
trained to distinguish between these two types of alarm
signal, students are unlikely to recognize the different
signals and the staff cannot be expected to find all
students to give them the appropriate commands. (Note
that the presence of a voice alarm system would provide a
significant advantage, as phased evacuation could then
be implemented with different messages being
transmitted to different areas. See Section 4.4.2.)
4.2.6 Alarm Verification Concept AVC
The Alarm Verification Concept (AVC) allows in-house
personnel to carry out a local investigation before the
municipal fire service is alerted or the building is
evacuated. This reduces the number of unnecessary calls
and is based on a dual timing principle. It is only
applicable in the “day/manned” mode of the fire detection
system.
In the “night/unmanned” mode (when a local
investigation cannot be ensured) the fire service will be
alerted without delay. Manual call points and sprinkler
flow switches also alert the fire service without delay (at
all times).
In the “day/manned” mode any alarm initiated from an
automatic smoke detector will generate a Local Alarm and
start the Presence Timer T1. If T1 times out without any
response from an operator, the fire service is called
immediately. If the alarm is acknowledged on the fire
alarm panel while T1 is running, the system recognizes
this as a sign that an operator is present. In this case the
Investigation Timer T2 is started for a predetermined
investigation period. The duration of this investigation
period should be determined in consultation with
the fire service.
If the local investigation verifies the existence of a major
fire, the fire service can be summoned immediately by
simply activating any manual call point. The fire service
will also be called if T2 times out. On the other hand, if
the local investigation establishes that only a minor, easily
dealt with fire exists, the fire alarm can be reset while T2
is still running.
Alarm Verification Concept