Civil Engineering Reference
In-Depth Information
Table 12.7
The Fire and Rescue Service classifi cation of false alarms
Type of false alarm
Description
Malicious
Where the operation of a fi re alarm system or a call to the Fire Service is made deliberately and maliciously
Good intent
Where a call is made to the Fire Service where the caller believes that there is a fi re or a fi re alarm system
has operated without a fi re having started
Good intent - electrical
Where the alarm is initiated by an electrical fault
Good intent - mechanical
Where the alarm system is initiated by a mechanical fault
dealing with real emergencies. They also disrupt work
patterns and valuable training programmes. Almost
half of the calls to the Fire and Rescue Service are false
alarms, and most of these are false alarms from fi re
detection and fi re alarm systems.
According to the Chief Fire Offi cers Association
(CFOA), a well-designed and maintained, fi re detection
and fi re alarm system should produce no more than one
false alarm a year for every 50 detectors fi tted, and no
more than one false alarm in any four-week period. For
large fi re detection systems, the aim must be to reduce
the level of false alarms well below that of one a year for
every 50 detectors.
False alarms are classifi ed by the Fire Service by
the initial event that caused the alarm to be raised. The
classifi cations are shown in the Table 12.7.
smoking near a smoke detector head; the underlying
cause, for example lack of control over contractors smok-
ing in the premises; and the root cause of a failure to have
and enforce adequate policies for smoking and the con-
trol of contractors.
In order to reduce the numbers of false alarms, a
thorough investigation into the circumstances should
be undertaken. In some instances managers will want
to involve the fi re alarm contracting company in order to
have the necessary competencies for the investigation.
The resultant action plan may involve redesigning part
of the fi re alarm system and/or improving the levels of
inspection, testing and maintenance.
The process
As soon as possible after the false alarm, inspect that
area and locate the break glass box, heat detector or
smoke detector that set off the alarm in order to ascer-
tain why the alarm was triggered. It should be noted that
the detector may be in a duct or above a false ceiling.
It will be necessary to call in a competent engineer to
assist the process on those occasions when:
12.5
Basic fi re-related investigation
procedures
The two types of fi re-related events that are covered
in these notes are false alarms and fi res. As with other
adverse events the basic procedure for investigating
false alarms and fi res involves a number of steps, start-
ing with an assessment of the level of investigation that
is required and concluding with the implementation of an
agreed action plan:
➤
It is diffi cult to locate the detector
➤
The control panel does not show where the relevant
detector is
➤
If no detector was triggered.
Whatever the outcome of the investigation it is vital that
there is an accurate record all the information about the
false alarm in the system log book.
If false alarms continue, it will be necessary to
analyse when the false alarms happen and where they
come from. This will help identify any pattern that may
help identify the cause (for example, cooking before
meal times or a boiler switching on early in the morning).
It is very likely that the investigation into the false
alarm will indicate that the alarm was caused by
equipment faults, malicious acts, human error, or activ-
ities near detectors.
1. The level of investigation
2. Involving other agencies/parties
3. Conducting the investigation
4. Gathering information
5. Analysing information
6.
Identifying risk control measures
7.
Agreeing and implementing an action plan.
Investigating the cause of false alarms
The purpose of investigating false alarms is to estab-
lish: the immediate cause, for example unauthorised
