3. Around 80% of all
UK fire deaths and
injuries occur in
dwellings
HMO occupants are
6 times more likely to
die in a fire than people
living in a single family
dwelling
4. Nowhere is the risk to life of fire greater than in
houses in multiple occupation, where a fire in
one dwelling can quickly spread to another
5. Unfortunately, an increased risk of fire
means an increased risk of false alarms
The most common causes of
“unwanted alarms” are usually a
result of tenant‟s activities…
• Toasting smoke
• Cooking fumes
• Steam from bathrooms/kitchens
• Aerosol/hair spray
• Candles
• Tobacco smoke
• Build-up of dust
6. Failure to reduce false alarms can lead
to unnecessary building evacuations,
irate tenants, system vandalism and
true alarm signals being ignored
7. Fire Statistics (12 months to 31 March 2009)
722,000 Attended Fires or False Alarms
326,000 Fires
396,000 False Alarms (Unwanted alarms) 54%
The Fire Industry Association defines an unwanted fire signal as:
Any fire alarm signal other than a genuine fire or test signal. BS
5839-1:2002 also defines a false alarm as a fire signal resulting from a
cause(s) other than a fire, and further sub-divides these into four categories:
1) Unwanted alarms
2) Equipment false alarms (fault or contamination)
3) Malicious or Hoax false alarms
4) False alarms with good intent (smell smoke from a bonfire)
8. Impact on the community of Unwanted Alarms
1. Diverting essential services from real fire & rescues (putting life at risk)
2. Disruption of business (downtime, time wasted, loss of business, theft)
3. Unnecessary risk to crew & public whilst responding (accidents)
4. Unnecessary risk of personal injury during building evacuation
5. Complacency “oh its just another false alarm” reduces effectiveness
of management plans and procedures
6. Disruption to arson reduction, community safety & fire safety activities
(education, smoke detectors, etc)
7. Impact on the environment of unnecessary appliance movements
8. Cost of attendance to Tax payers - Council Tax
9. Fire & Rescue Services are considering billing the responsible person
for call outs to unwanted alarms, where due diligence cannot be
demonstrated
9. BS 5839-1:2002 (Section 3 Limitation of false alarms)
The role of the installer is simply to install the system in
accordance with the requirements of the designer. However,
where, during installation, an installer identifies conditions in the
building (e.g. environmental conditions) that might result in an
unacceptable rate of false alarms, the designer, purchaser or
user needs to be informed, so that the need for modification of
the design can be considered.
Verification of compliance with this standard includes verification
that suitable steps have been taken by all parties to ensure that
false alarms can be limited as far as reasonably practicable.
10. BS 5839-1:2002 Design Certificate
Work with those responsible for buildings to ensure that where
a fire alarm and detection system is installed or is to be
installed, it utilises the most appropriate devices to reduce false
alarms
11. BS 5839-6:2004 (12.2 Recommendations)
All fire detection and fire alarm systems complying with this part of BS5839
should have accessible means of silencing fire alarm signals,
suitable for use by the occupiers of the dwelling.
Grade A systems should be provided with silencing facilities that comply
with the recommendations of 16.2.1g) and 16.2.1h) of BS 5839-1:2002 -
A facility should be provided to enable silencing of alarm signals
- Alarm signals should not be silenced automatically
In Grade D and Grade E systems, means should be provided for silencing
short term unwanted alarms. Provided the facility can be operated by
occupiers of the dwelling when standing at floor level.
A delay of up to two minutes between the operation of a detector in one
dwelling unit and a fire alarm signal in other dwelling units
Provision for isolating a dwelling‟s detectors and sounders should activities
be taking place that could cause a false alarm
12. BS 5839-6:2004 Design Certificate
Work with those responsible for buildings to ensure that where
a fire alarm and detection system is installed or is to be
installed, it utilises the most appropriate devices to reduce false
alarms
13. Sources of unwanted alarms (CASE 1)
House in multiple occupation:
problems associated with cooking
fumes and steam
When a smoke detector in an area adjacent
to a kitchen or bathroom is connected to a
fire alarm system, it should not render the
whole system vulnerable to a false alarm
originating from that area due to cooking
fumes and steam
14. House in multiple occupation: Example ground floor
S S S
H S
S
S = Automatic smoke detector triggered in Hallway
and / or Lounge adjacent to Communal Kitchen
when cooking.
15. House in multiple occupation: Example 1st floor
S
S
S S
S = Automatic smoke detector triggered in Hallway adjacent to
Communal Bathroom after immediate use due to steam.
16. House in multiple occupation: Example 2nd floor
S
S
H
S
S = Automatic smoke detector triggered in Hallway adjacent to Bathroom after
immediate use due to steam or from cooking fumes when kitchen was in use.
S = Automatic smoke detector triggered in Bedroom after immediate
use of En-suite shower.
17. Sources of unwanted alarms (CASE 2)
Halls of residence: problems associated with cooking fumes
S When a smoke detector in an area adjacent to a communal kitchen is
connected to a fire alarm system, it should not render the whole system
vulnerable to a false alarm originating from that area due to cooking
fumes.
S
S S S S
S
H
18. Sources of unwanted alarms (CASE 3)
Sheltered Housing: Problems associated with cooking fumes
& steam
S When a smoke detector in a
house/flat is connected to a
fire alarm system, it should
not render the whole system
vulnerable to a false alarm
originating from that S
house/flat due to cooking
fumes and steam. Also
consider areas adjacent to
communal kitchens. S
19. Technical solutions to prevent unnecessary building evacuations
1. Use of Analogue smoke detection systems which are likely to offer
better immunity to false alarms than conventional two-state fire
detection systems as they provide a pre-alarm warning, which
enables investigation of conditions that, if no action is taken, would
lead to an unwanted alarm.
2. Use of a multi-criteria sensor
3. Use of a “Hush” button to manage unwanted alarms
20. Designed to work with widely available open
protocol fire alarm systems, C-TEC‟s Hush Button
tackles all of these issues head on.
21. There are two aspects to fire detection and alarm systems
in HMOs & Sheltered Housing - dwelling units and
communal areas
dwelling unit dwelling unit
dwelling unit dwelling unit
Communal
area
dwelling unit dwelling unit
22. A typical “Grade A” EN54-2/4
communal (mixed) system
230V 230V
Grade D Mains/battery Grade D Mains/battery
alarms to BS5446 alarms to BS5446
Grade A
EN54-2/4
Fire alarm
system
230V 230V
Grade D Mains/battery Grade D Mains/battery
alarms to BS5446 alarms to BS5446
230V 230V
Grade D Mains/battery Grade D Mains/battery
alarms to BS5446 alarms to BS5446
FACIE
24. The silence button is often on the alarm itself and cannot be operated
whilst standing at floor level
There is no way of easily isolating a detector should „hot works‟ be
taking place. If Mains is disconnected the battery still needs removing
No feedback on system integrity outside the dwelling unit (vandalism
and/or flat batteries not reported elsewhere)
Installation is often the responsibility of two organisations - an
electrician fits the mains alarms in the dwelling units and a fire
specialist fits the BS5839-1 system in the communal area(s)
Often no option for connecting beacons and/or vibrating pads for
Equality Act compliance
25. A typical “Grade A” EN54-2/4
single system (conventional) solution
Grade A
EN54-2/4
Fire alarm
system
FACIE
27. There is no way of silencing a local alarm from within a dwelling unit
(this has to be done at the main panel)
There is no way of temporarily isolating a detector from a dwelling
unit should „hot works‟ be taking place (this has to be done by
disabling and then re-enabling the relevant zone at the main panel)
29. Utilises readily-available cost-effective
“Open Protocol” fire alarm technology
Each Hush Button can be looked upon as a
fully-monitored single zone conventional fire alarm
system that can sit on a communal fire alarm
panel‟s analogue loop (max. 20 per loop).
Use of analogue fire system technology offers
higher unwanted alarm immunity, with the
capability of configuring warning devices for
phased evacuation.
30. Typical Hush Button solution used for Dwellings
Conventional smoke/heat Conventional smoke/heat
detectors with base detectors with base
sounders sounders
Grade A EN54-2/4
Analogue Addressable
Fire alarm system
Conventional smoke/heat Conventional smoke/heat
detectors with base (Apollo XP95/Discovery detectors with base
sounders or Hochiki ESP) sounders
Conventional smoke/heat Conventional smoke/heat
detectors with base detectors with base
sounders sounders
FACIE
31. Analogue Analogue
loop IN loop OUT
Analogue loop
wired in two core
enhanced fire
resistant cable
Max. 20 Hush
Buttons per loop
32. Call point must be
fitted with 330 ohm
resistor supplied
with Hush Button
Conventional
detector circuit
wired in two core
enhanced fire
resistant cable
Max. length 100m
