The Importance of Early Warnings
By Neil Perdell, National Technical Manager, Aico Limited
When it comes to escaping from a fire in the home, time is vital. Those extra
few seconds can make all the difference between safety and injury or even death.
Since their introduction, smoke alarms have proved critical in providing people
with a warning and giving them time to escape from a fire; they've made a real,
undisputed difference. The task for fire professionals now is to ensure that people
are not just given warning of a fire – but are given the earliest possible warning of a fire.
The recently published Summary Fire Statistics United Kingdom 2006 clearly show that some groups are more vulnerable in a fire than others. At
first it would seem strange that babies under one year old are much less likely
to perish than children aged one to four. Babies are, after all, even more helpless
than toddlers aren't they? With a little more thought, it's clear that babies
tend to sleep in a room with their parents, whereas the one to four year olds
may have their own room. In a fire, parents may have time to snatch up a baby
from within their bedroom, but rescuing toddlers from separate rooms takes extra
valuable time – time they may not have. The elderly too, are more vulnerable as
they may have hearing problems or are just slower in escaping. There are no figures
for the infirm or disabled, but it's no stretch of the imagination to understand
that they need more time to escape than the able bodied.
Families with children, the elderly, the disabled: that profile fits a lot of
tenants. What's more, even the fastest, healthiest of young adults will benefit
from the earliest possible warning. It's just common sense.
There have been obvious steps to improve early warning times. Ensuring that the
right alarm type is correctly situated in the right application, for example,
or checking audibility levels in crucial areas, such as in the bedroom behind
a closed door. Good maintenance practice is another. Interconnection of all the
alarms in the property is essential if early warning is to be achieved.
There is another totally logical step to take – install more alarms in the property.
It may be a daunting prospect, but it's an idea with powerful advocates. It's
perhaps best reflected in the decision as to whether to install a Grade D, LD3
system or an LD2 system into a property. Basically, a Grade D, LD3 system consists
of one mains powered alarm in the hallway and another upstairs on the landing,
interconnected together. A Grade D, LD2 standard on the other hand involves an
additional heat alarm in the kitchen and a further heat or smoke alarm in the
main living area; all four alarms being interconnected. Those who favour LD2
as 'Best Practice' argue that it is not acceptable that 'Existing Tenanted Properties'
should have less safety coverage than New Build or 'Materially Altered Dwellings'
where LD2 is the recommended level of cover.
There are problems, however, with simply increasing alarm coverage. Quite aside
from the cost of alarm units, there is all the extra time and associated installation
costs, particularly concerning interconnection. Interconnection is vital. It's
a cornerstone of any early warning policy. When one alarm sounds, every alarm
in the property is triggered and sounds. However, connecting all the alarms together
by hard wiring is a big job – and expensive too, sometimes to the point off being
off-putting. Walls and ceiling may need an unsightly trunking run. Floors and
carpets may need to be wrenched up and then replaced. Tenants may hate the chaos
and disruption – and actually withhold permission.
Fire industry professionals have been left with the dilemma of recognising the
need for greater coverage and interconnection to improve warning time – but finding
it difficult to achieve.
Manufacturers recognised this too, and one of the strongest responses to the
problem has come with the introduction of wireless interconnection. Now, it's possible to interconnect all alarm types through the use of wireless
signals rather than hard wiring, using systems such as Aico's RadioLINK technology.
With no hard-wired interconnection, it's far quicker, simpler and less disruptive
to install even a much larger and more sophisticated alarm system – and to make
additions or changes when a tenant needs changes. Using well-proven wireless technology,
safety has not been compromised and such systems have proved every bit as reliable
as traditional old hard wired systems.
There's a further obstacle, however, to providing the best possible early warning,
and that concerns how smoke and heat alarms actually work. Optical, ionisation
and heat alarms – the three types most commonly in use today – are individually
designed to be very good at picking up one particular kind of fire. Unfortunately,
there is more than one type of fire.
Fire can smoulder away for ages, or it can flare up suddenly and violently. Some
fires produce a lot of heat very quickly, while others produce little heat but
lots of smoke particles in the early stages.
When deciding which alarm type to use, specifiers have tended to go for the 'best
guess'. That is, they look at the type of fire most likely to break out in an
area and choose the alarm type most applicable. This is not ideal and does not
fully cover all risks. In a downstairs area covered by a single optical alarm
in the hall, for example, the threat might come from a slow smouldering fire from
electrics or furnishings – but it also may come from a fast, violent fire out
of the kitchen. Here, a heat alarm would have given earlier warning.
Thankfully, manufacturers are beginning to understand this problem and respond
to it with new products designed to properly cover multiple fire types and risks.
Aico has launched its new Ei2110 Multi-Sensor which combines two separate sensing elements – Optical and Heat – in a single
Multi-sensors were once the province of big panel systems only, protecting buildings
such as hotels and offices. Now however, that powerful and advanced technology
is at last being put at the disposal of those concerned with domiciliary fire
safety in dwellings. Given that the vast majority of fire deaths occur in the
home, some might say such protection technology is long overdue in its arrival
In practice, this means that the use of a Multi-Sensor offers an improved response
to all likely fire types – and better early warning. For an application where
a specifier or installer cannot be completely sure of the fire type threat, it
provides a simple solution. In some applications, it can also help reduce costs
by eliminating the need for two separate units.
Interestingly, Aico has made sure that its new Multi-Sensor is fully compatible
with its RadioLINK wireless technology, so both technologies can be combined to
tackle the early warning issue.
If we wish to further cut fire death and injury, it's essential that people are
provided with the earliest possible warning in a fire situation. It's a very positive
thing that manufacturers are now starting to offer specifiers and installers tools
with which to tackle the problem. The technology is innovative, yet reliable.
Larger systems offering greater coverage are no longer such a daunting prospect
as they were thanks to wireless technology. At the same time, the advent of the
Multi-Sensor means that all types of fire can be detected in the earliest possible
time. With time such a crucial element in survivability, it's certain that lives
will be saved.
(doc:124 V1.0). Our articles are reviewed regularly. However, any changes made to standards or legislation following the review date will not have been considered. Please note that we provide abridged, easy-to-understand guidance. To make detailed decisions about your fire safety provisions, you might require further advice or need to consult the full standards and legislation.