PSISeptember2017a

FIRE SAFETY
False Fire Alarm Management
The latest innovations
in fire system
technology offer a
number of solutions
for minimising false
alarms, writes Aston
Bowles (marketing
manager at
Advanced). The key is
to verify whether
there’s a real fire
before the next stage
of the building
evacuation strategy
commences
alse alarm reduction should be considered
Fas part of the risk assessment before any
specification is written. Each building will
have different users and specific circumstances
that may require unique verification,
investigation and evacuation processes. All of
this can occur under one roof and over multiple
floors, so flexibility is very definitely the key.
Intelligent detectors
The industry has taken two main approaches:
one focused on detector head technology that
looks at reducing incorrect signals in the heads
themselves, the other an approach that centres
on signal processing and decision-making in the
fire control panel. Some forward-thinking
manufacturers are combining the two into
approaches to combat the causes of false
alarms from multiple directions.
The development of intelligent detectors, the
most sophisticated of which use smart
algorithms to differentiate between real fires
and false signals perhaps caused by steam or
cooking smoke, has accelerated in recent years.
Detectors can also be used together or in
other modes specifically designed to reduce
false alarms. For example, multi-sensor
detectors may be switched between heat and
smoke in order to confirm a signal. Several
detectors may also be combined, for example
using double-knock or coincidence to confirm a
genuine signal.
Automatic, addressable fire systems will
analyse detector signals and then, if the signals
match expected criteria, activate a range of
verification and confirmation procedures. A
good fire system can do a huge amount
automatically and much can be achieved with
minimal human intervention.
However, one of the key ways to reduce false
alarms is to involve people and, in order to make
this effective, some manufacturers have
introduced dedicated false alarm input devices.
Verification time extensions
The AlarmCalm Button, part of Advanced’s
AlarmCalm solution, allows the verification time
on a system to be extended by the occupant of a
room if they believe the signal to be ‘false’ in
their area. If the signal clears then the system
will return to normal. If it persists beyond the
pre-set verification time then the system will go
into full alarm and implement the next phase of
‘cause and effect’ such as evacuation.
Involving people, even trained individuals,
means fail-safes must be strong. The AlarmCalm
button can only be pressed once before a
system reset and times are programmable. If an
alarm signal has been verified by the panel or if
a manual Call Point is activated, the system will
enter a full fire alarm condition immediately.
Equally, if a pre-set number of areas are in
verification (ie detecting potential fire signals)
the system will go into full alarm. The benefits
of involving the occupants of, say, a student
accommodation building are, however, pretty
hard to ignore.
Another key aspect to consider when
specifying a false alarm management system is
ease of system management. Can the system be
divided precisely into different areas? Can
points be managed singly or grouped, as in an
apartment, and is it easy to programme and
install? Wiring and configuration on larger sites
can add much complexity and cost.
Intuitive in operation
Equally, priority should be given to selecting a
system that’s acceptably intuitive for staff and
designated users alike to operate. The ability to
share information in dynamic fire conditions has
also developed rapidly. For example, some
touchscreen displays are a key tool that can
make it far easier to identify the location and
status of an alarm.
Careful consideration should also be given to
how the system will be monitored, serviced and
maintained. There are a growing number of
solutions that allow fire systems to be remotely
monitored and controlled over the Internet,
which means an engineer can arrive with a plan
agreed and all spare parts required, in turn
minimising disruption to the building’s users.
In summary, then, false fire alarms most
certainly remain a problem, but the industry has
the tools at its disposal to radically reduce them
and, indeed, their impact. This will certainly
involve trained professionals at the design and
specification stage and, possibly, the trained
occupants of a given building.
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