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See
it in action - Real
Media streaming video links - 56k
modem or 256k
broadband - thermal image video footage of independent
trials shows comparison of exit behaviour with and without DSE.
Despite advances in Fire Detection
systems to detect fires, these systems do nothing to actually
guide people to safety. They rely on people's ability to find
their way out using exit signs.
In
a smoke filled area, the emergency exits and signs may be impossible
to locate by sight and an alternative method of guiding people
along the nearest escape route is imperative.
Voice Evacuation systems can tell people where to go, but not
show them how to get there.
The
use of directional sound to mark exits enables identification
of exit locations that are obscured. Additionally, under non-smoke
conditions, the use of The Localizer®
Directional Sound Evacuation (DSE) beacons draws attention to
Emergency exit signs and nearest exits which are often ignored
because they are so familiar and not normally important.
The Localizer® "audible exit sign" enhances fire
alarms and lighting systems, and we are licensing the technology
to multinational companies in North America and Europe. Research
observed by the British Government has shown that The Localizer®
can reduce evacuation times by as much as 70% in smoke and 35%
in perfect visibility.
These
sound-equipped beacons are obviously advantageous to people
with visual impairment, and have also been shown to benefit
individuals with learning difficulties and hearing loss. The
broadband sound, which is totally independent of language constraints,
consequently makes the beacons suitable for all nationalities.
Commonly
held myths
The
fire safety industry has its roots in over a century of tradition
and is, by its very nature, somewhat conservative. Many
"accepted facts" of the industry are based on little or
no research. Here are a few of the myths - and what research
teaches us:
Myth:
People do not travel through smoke when evacuating.
Reality:
Given the choice, naturally people will avoid going through
smoke, however people
escaping fires frequently have to travel through areas filled
with smoke.
According to Prof J.L. Bryan of the University of Maryland who
studied survivors from 400 different fires, 53% of survivors
from fires admitted to travelling through smoke. P.G. Wood of
the Building Research Establishment in the United Kingdom reported
similar findings. In the September 11th World Trade
Centre tragedy, approx 90% of the occupants survived, however
people struggled to find emergency staircases because the entrances
were from a lobby that was filled with smoke.
Myth:
Using new types of lighting can dramatically improve visibility in
smoke
Reality:
Research into visibility of exit signs and lighting is carried
out by looking through a glass window
into a smoke filled room or using theatrical smoke.
This ignores the irritant effect
of smoke on the eyes - which are attacked and quickly
become incapacitated.
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Research,
carried out by the Building Research Establishment (UK),
using volunteers in theatrical (white) smoke illustrates how
visibility of different types of exit signs vary in smoke.
It ignores the effect of real smoke on the eyes, or
toxicity, however it does illustrate that NONE of these
technologies is visible at over 1.5 metres in dense smoke
(Optical Density 3m-1). At OD 1m-1,
the best technology was visible at just 4 metres whilst
Photo-luminescent signs were visible at just over 1m.
Hearing
is not affected by smoke.
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Myth: In an emergency people panic and fight for survival.
Reality: People are calm and cooperative.
Numerous reports of real incidents have shown this. September
11th produced many examples of extraordinary heroism and calmness
in the face of disaster. Only in rare instances has selfish
behaviour been observed.
Myth:
Smoke rises to the ceiling and people evacuating can bend or crawl
to safety in clear air, breathing normally underneath.
Reality:
Whilst it
is true that smoke rises when mixed with hot gases, F.R.S. Clark
warns "Smoke
density is not always lowest near the floor. Smoke tends to
travel along the ceiling when it mixes with hot, buoyant fire
gases. As these gases cool, however, the smoke sinks and eventually
fills the entire space. Smoke may also be dispersed evenly through rooms by
forced ventilation systems and by the action of sprinklers activated
by the fire. Under these conditions low placement of exit signs
may offer little advantage”. (Clark,
F.R.S. Strategies for improving visibility in fires. Institute
for Research in Construction, National Research Council of Canada,
Canadian Building Digest 246, January 1988, 4pp.)
Water
mist extinguishing systems cool hot gases close to the seat of the
fire - breaking down stratified smoke layers and eliminating
the "safety gap" at floor level.
Martin
Shipp, Senior Inspector of Building Research Establishment, also
confirms that " whilst smoke may be stratified in a still
air environment, the movement of people through the area can
quickly disturb this stability and result in smoke down to floor
level".
Dusseldorf Airport fire
- official report extract:
"Seven
victims did go by lift from the parking lot on the roof top
directly into the deadly smoke. When the door opened, the dense
smoke hindered the light beam so that the lift doors could not be
closed again. The nearest exit was 3 metres away from some of the
victims but they could not find it and died."
Channel Tunnel fire - official
report extract:
"The driver of the incident train was unable to leave
his cab to organise the evacuation of passengers because the smoke
was too dense. The Chef de Train was unable to find the evacuation
route within the tunnel because of the thick smoke and decided to
keep everyone on-board the incident train until the arrival of the
emergency services".
Scandinavian Star fire
- official report extract:
"We do know that emergency lighting and marking signs do
not help to distribute people among the evacuation routes
available.
The committee recommends that
a requirement be introduced that audible signals with a
sound that clearly distinguishes them from the alarm bells be
installed by the exit doors in escape routes on board
passenger ships, as directions for escape in conditions of
reduced visibility."
Note: This recommendation was pursued by Governments
of UK & Germany in their proposal to the United Nations
Manchester
Aircraft fire - official
report extract:
"Many survivors spoke of their inability to see due to the
extreme density of the smoke and chemical effects on the eyes.
In
addition it is also apparent that the effect of such atmospheres
is to rapidly suppress any ability of those affected to shout, due
to respiratory and acidic gas 'burning' effects on their throats.
These sensory deprivations might be effectively countered by the
use of automatic audio-attraction devices to guide evacuees
towards viable exits. Research should be undertaken to assess the viability of
'audio-attraction' and other techniques designed to attract passengers towards
viable exits when speech and vision is impaired in smoke and
toxic/irritant gases."
Paper
by Professor Deborah Withington - The Use of Directional Sound
to Aid Aircraft Evacuation
Myth: Low Location Lighting guides to safety in smoke
Reality: What research was done prior to its introduction? There are limitations to
its effectiveness:
It cannot provide
guidance in open spaces
In normal installations it
cannot show which way to the nearest exit.
In smoke, eyes are attacked
so its visibility is poor
Electro-luminescent systems
are very expensive
Photo-luminescent systems
are largely invisible in smoke
Nieuw Amsterdam fire
- official
report extract:
"By
the time the passenger re-entered the corridor, it had become
filled with smoke. Crouching to move along the corridor, the
passenger became disoriented and was eventually found by a
crewmember and taken to safety. The ship’s electroluminescent
low-location lighting system was in operation."
Manchester
Aircraft fire - official
report extract:
"Against this background of research and survivor evidence it
is difficult to substantiate the rationale behind current
regulatory moves towards the introduction of low-level
'escape-path' lighting to assist evacuations from smoke filled
cabins. Under such circumstances the net safety-gains
from such a requirement are likely to be minimal unless the
passengers' eyes are protected.
"
Recently
awarded the Fire Industry Council's Innovative Product
Award and the Royal Institute of Naval Architecture ~ Lloyds
Register Safer Ship Award, DSE beacons are the result of over 7 years of research
with a substantial body of independently
verified trials which have shown its effectiveness in a number
of different environments:
Buildings
Aircraft
Ships
Tunnels
Download Summary fact sheet on
Directional Sound Evacuation (236k pdf)
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