Note: Descriptions are shown in the official language in which they were submitted.
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PROTECTIVE HOOD AND ORAL-NASAL MASK
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a respiratory system
and more particularly, is concerned with providing fresh,
breathable air from contaminated air for use in aircraft and
providing visibility to escaping aircraft passen~ers involved
in an aircraft fire as well as other vehicle use and
non-vehicle use. When installed in an aircraft the present
invention embodies the function of the present supplemental
oxygen mask, common in the art and referred to as the "gold
cup", providing supplemental oxygen in cases of aircraft
decompression.
Description of the Prior Art
In the past, many smoke hoods have been designed to
protect the wearer by providing $resh breathable air from air
in environments contaminated by smoke and noxious gases.
U.S. Patent 4,559,939 issued December 24, 1985 to
Levine discloses a supplemental air tank and hood system. U.S.
4,116,237 which issued to Birch, discloses a supplemental air
tank and hood system. These devices only provide dry filters
that mainly remove particulates.
U.S. Patent 4,554,683 which issued November 26, 1985
to Wong provides a barrel shaped smoke hood to provide the
wearer with a volume of breathable air within the hood
sufficient to sustain the wearer for a short period of time.
This hood works in situations involving high
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rise building fires where fresh, breathable air is available
for a period of time prior to contamination by smoke and
noxious gases. The major drawback of this hood when used in
the aircraft fire situation, is the consumption of the fresh,
breathable air and generation of carbon dioxide within the
hood, leading to hypercapnia and anoxia. In the aircraft fire
situation, the time from onset of fire to time of evacuation
may exceed the capacity of the invention disclosed in U.S.
Patent 4,554,683 to Wong.
The instant invention provides a oral-nasal mask which
may be connected to any air supply and may be connected to an
aircraft's emergency air supply and an air purification system
through a wet chemical filter such that fresh, breathable air
is available to the passenger at any point during the fire
thereby eliminating the need to "fill" the hood with fresh air
prior to donning the hood. The oral-nasal mask provides
breathable air prior to placement of the hood over the head of
the user and after placing the hood over the user's head.
While U.S. Patent 4,554,683 to Wong does mention that
optional filters may be attached to the barrei shaped hood, the
hood may not provide the passenger with fresh, breathable air
prior to the passenger's asphyxiation of suffication due to the
smoke and noxious fumes even with the incorporation of the
optional filters. Because the hood allows atmospheric air,
which is likely to be contaminated in the aircraft fire case,
into the hood prior to incorporation on the wearer, the wearer
will have to take several breaths of contaminated air before
any filtering system allows the purified air to enter the
barrel shaped hood.
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Survivors of recent aircraft fires have stated that one and two
breaths of the smoke and noxious gases present in the aircraft
fire resulted in the passenger's lungs feeling solidified and in
the passenger's experiencing extreme sleepiness. The passenger~
of aircraft fires cannot risk taking several breaths of the
contaminated, toxic, atmospheric air within the Wong hood prior
to receiving the purified air where s~ch immediate and critical
symptoms occur from one or two breaths.
The instant invention provides a compact oral-nasal
mask and hood. The invention inco~porating the oral-nasal mask
does not require a user or passenger to take several breaths of
the contaminated, surrounding atmospheric air prior to receiving
the fresh, breathable air. The oral-nasal mask is of relatively
small volume, just sufficient to cover the user's or passenger's
mouth and nose region such that the passenger will receive fresh,
breathable air immediately upon the user's or passenger's first
breath from a supply or from the aircraft supply and/or from the
surrounding air filtered through the wet and dry purification
filter.
Further, traditional filters are not effective in
removing some toxic materials, specifically Hydrogen Cyanide,
Hydrogen Chloride, Hydrogen Floride, and Carbon Monoxide, some of
the more lethal and commonly occurring gases in modern building
fires or in airplane fires. The disclosed chemical filter system
employing both a wet and dry chemical cleansing system within the
instant invention is more effective in reducing levels of
~ydrogen Cyanide, Carbon Monoxide and other gases which enter the
filtration sy~tem. The wet filter scrubs the incoming
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contaminated air in a wet bath of bases to neutralize the
acidic toxic gases. A porous plastic material is used that
allows the liquid to remain inside the purifier but allows the
user's lungs to draw the contaminated air through the interior
of the porous plastic section. The porous plastic material is
a hydrophobic material composed of polyethylene or other common
plastics, a tradename common in this application is POREX
POROUS POLYETHYLENE.
Smoke hoods that have been proposed are disclosed in
several prior patents including: U.S. Patent 4,554,683; U.S.
Patent 4,231,118 which issued November 4, 1980: U.S. Patent
3,562,813 which issued February 16, 1971 and U.S. Patent
3,458,864 which issued August 5, 1969. However, the novelty of
the instant invention is the relatively small compact
respiratory system for use in a building or vehicle or an
aircraft and in leaving same. The respiratory system also
includes a wet chemical scrubbing filter for cleaning a room or
cabin air of toxic and other gases connected to the oral-nasal
mask, the combination of a collapsible hood that is connected
to the oral-nasal mask allowing the oral-nasal mask to be
placed over the user's nose and mouth prior to covering the
user's eyes with the hood. While the above mentioned patents
utilize the protective hood to surround the user with
breathable air, the protective hood in the instant invention
has as one of its primary purpose, not to surround the user
with fresh air, as the oral-nasal mask already provides this,
but to insulate the user's eyes from the irritating effects of
the noxious gases and soot disposition by filling the hood with
the user's exhaust gases from the oral-nasal mask. In
addition, the present invention provides the
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passenger with fresh, breathable air before the user or passenger
dons the smoke hood. This psychological advancement provides the
passengers with the security of fresh breathable air before
surrounding their heads with the air impervious hood.
In addition, no other prior art incorporates a dual air
supply system providing the user or passenger with either, or
both, fresh air from the local supply aircraft's emergency air
source if provided or from the contaminated surroundings by
filtering same through a wet chemical filter. The instant
invention may rely entirely upon the ambient air supply to
provide the user or passenger with fresh, breathable air from
contaminated surrounding air for a temporary period ~ufficient to
escape from the room, the surrounding area or the cabin of an
aircraft. The filtering system is stored in the cup-like oral-
nasal mask. The hood that may be easily placed over the user or
passenger is conveniently attached to the outside of the oral-
nasal mask.
Consequently, a need exists for an aircraft respiratory
system incorporating both an oral-nasal mask providing the
passenger with fresh, breathable air from alternative sources,
the aircraft's emergency air source and an air purifier source
that removes contaminants from the surrounding cabin air, and a
protective hood to insulate the passenger from the smoke and
noxious gases associated with an aircraft fire to improve
passenger's visibility by filling the hood with the user's
exhausted gas during an escape from the aircraft. The same
compact respiratory system may be used in other vehicles or by
firemen or the like. The wet chemical air purifier continues to
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work after the user detaches himself from the bottled air or the
aircraft's emergency air in order to exit the area, rOQm or
aircraft.
SUMMARY OF T~E INVENTION
The pre~ent invention provides a respiratory ~ystem for
users of rooms and various areas that may have emergency fires as
well as pa~senger~ of aircraft involved in aircraft fires
sufficient to temporarily maintain the user or passenger's air
supply and visibility as well as for other aircraft emergencies
such as loss of cabin pressure at high altitudes. The instant
invention embodies in the existing drop down oral-nasal mask two
air supply systems. First, the ordinary bottle emergency air or
airplane emergency air supply system that allows the user or
passenger to breath directly from the emergency air source.
Second, from a filtering system, a wet chemical air purifier,
stored in the cup shaped mask that scrubs toxic and other gases
that are taken in from the surrounding room, area or cabin air to
purify same for human use in breathing in the event of a fire in
the room, area, or cabin. A hood is connected to the outside of
the cup shaped mask for easy access after the user or passenger
places the mask over his nose and mouth. Such a dual respiratory
oystem with a small compact wet chemical air purifier has not
been incorporated in prior aircraft respiratory systems.
Accordingly, the instant invention for providing
temporary life support to permit each user or passenger involved
in a room fire, area fire or aircraft fire includes the ordinary
drop down oral-nasal mask to cover the passenger's mouth and nose
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reaion and to surround the passenger's mouth and nose eegion with
fresh, breathable air, a protective hood to insulate the user's
or passenger's eyes from the irritant effects of smoke and
noxious gas when the hood is filled with the usel's exhaust
gases, and an air purifier to provide the user or passenger with
fresh, breathable air in addition to the aircraft's emergency air
source or to provide the user or passenger with the fresh,
breathable air after the bottled air or aircraft oxygen is
depleted or turned off or the passenger has disconnected himself
from the bottled air or aircraft supply when exiting the room,
area or aircraft. In the instant invention, the preferred
embodlment allows the user or passenger to initially breath the
two types of air fir6t, the bottled air or the aircraft's
emergency air source and second, the purified room, area or cabin
air ~ource through the wet filter.
It iæ an object of this invention to provide in a drop
down assembly or pull down assembly or pull out assembly: an
oral-na~al mask, an air purifier system stored in the cup shaped
mask, and a hood connected to the outside of the cup shaped mask
for use in an area or vehicle as well as when exiting the area or
vehicle. In an aircraft installation this assembly would be the
overhead passenger service unit. This invention would replace
the ~gold cups~ in that assembly.
Another objéct of this invention is to provide a wet
filter and system~ that allow the user to breath from an air
supply and from surrounding air through the wet filter.
In accordance with these and other objects which will
be apparent hereinafter, the instant invention will now be
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described with particular reference to the accompanying drawings.
BRIEF DESCRIPTION OF TEII: DRA~INGS
In the drawings:
Figure 1 is a perspective view of the respiratory
system emerging from the ceiling on a lanyard and an oxygen tube
of the aircraft with the oral-nasal mask, wet and/or dry chemical
air purifier system behinæ a sealed cover, and hood under a cover
connected to the outside of the mask.
Figure 2 is a perspective view of a user or passenger
user grabbing the respiratory system.
Figure 3 is a perspective view of the user or passenger
relea~ing the wet chemical air purifier system from behind the
cover and in breaking the seal between the oral-nasal mask and
wet chemical air purifier system and extending the purifier
sy6tem away from the cover with the breathing tube extended.
Figure 4 is a perspective view of the oral-nasal mask
and air purifier ln its extended position for use and the lanyard
disconnected.
Figure 5 i8 a view of the oral-nasal mask and wet
chemical air purifier in position on the user's or passenger's
head.
Figure 6 is a perspective view of the user or passenger
beginning to release the hood on the oral-nasal mask.
Figure ~ is a perspective view of the user or passenger
having pulled the mask over his head and the oral-nasal mask.
' Figure 8 is a front view of the user or passenger in
Figure 7 illu~trating the supply air tube or the stored air tube
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severed fro~ the bottled air or aircraft tc allow the ~ser or
passenger to exit the room, area or aircraft.
Figure 9 is a perspective view of the user or passenger
in Figure 7 with the hood stored under the hood cover.
Figure 10 is a cross section of the purifier shell
showing the air passages and the internal configuration of the
wet and dry air purifier.
Figure ll is a top view of Figure 10 with the right
portion tilted upward.
D~SCRIPTION OF T~E PREFERRED EMBODIMFNT
This is a new and improved invention for a respiratory
system 12 shown in Figures 1 and 2, for use by an individual
carrying bottled air or in a vehicle, such as an aircraft. Tbe
system 12 provides users and aircraft passengers with fresh,
breathable air in case of smoke, fire or rapid decompression from
an air supply or an aircraft supply and from purified room, area
or cabin air and to improve the user's or passenger's visibility
and breathing during an escape when the air supply or aircraft
supply is disengaged or depleted. The resplratory system 12,
includes an oral-nasal mask 1, composed of semi-flexible material
constructed from film or injection molded. The mask includes an
open cup-shaped interior 5 shown in Figure 4, to engage upon the
user's or passenger's mouth and nose region 2 shown in Figure 5,
to isolate the user'~ or passenger's mouth and nose region 2,
from the contaminated area, room or cabin atmosphere surrounding
the user's head. The oral-nasal mask 1, is generally cup shaped
with edges 7 and 7', contoured to substantially conform to a
human face and particularly, to contour to the passenger's
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cheekbones 8, and chin 9. This prevents the inflow of area air
into the nose-mouth piece.
Door 50 of the storage container opens either manually
or automatically. Illustrated is an airplane's storaye container.
The door 50 hangs down on hinge 54 to open the small overhead
compartment to allow the respirator system 12 to drop out as
sho~n in Fig~re 1. The system 12 may be pulled out of the small
storage container 56. The oxygen or air tube 58 and lanyard 60
are connected to the respirator system 12 and the inside of the
small storage compartment 56. The user'~ hand 62 qrabs handle 64
and pulls as shown in iFigure 2 the purifier shell 66 as shown by
arrow A in Figure 3 from the mask 1 and upper shell 70. The
plastic seal 68 is broken as shown in Figure 3 and cap 66 is
placed in an in-u6e position as shown in Figure 3 exposing the
outer filter 72 of the wet chemical air purifier 14 that is below
filter 72. The purifier shell 66 is supported by lanyard 60.
An elastic band 10, i8 attached to the oral-nasal mask
1, near the edges 7 and 7'. The passenger extends the elastic
band 10, behind the passenger'6 head 11, to compress the oral-
nasal mask 1, against the passenger'6 mouth and nose region 2 to
maintain oral-nasal mask 1, with a substantially airtight seal
around the passenger'6 mouth and nose region 2 as shown in
Figures 5. The elastic band would allow exhaled air to move out
around the edges 7 and 7' by reason that the nose-mouthpiece has
a one-way valve to allow air into the mouthpiece from tube74.To
keepa tight seal at all times, one way exit valves 90 located on
the nose-mouthpiece 1. The elastic band 10, also supports the
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rest of the respirator~ syten( 12, in place without urther
assistance. The elastic band 10, is flexible and is easily
folded into the interior 5 of the oral nasal mask 1 along with a
portion of the wet chemical air purifier 14, for storage
purposes.
The oral-nasal mask tube 58 is connected to the
purifier shell 66, with a passageway shown by arrows B, C, D, E
and F shown in Pigure 10 into the oral-nasal mask 1. The tube 74
extends into the interior 5, or the oral nasal mask 1 and may
have a one-way valve in tube 74. The end of tube 74, of the
oral-nasal mask tube 74, extends into the interior S, of the
ora~-nasal mask 1, are unblocked and provide the path for fresh,
breathable air to enter the oral-nasal mask 1. The sealed air
bag 80 has a one-way flapper valve 84 to allow air to come into
the air passageway as shown by arrow B'. Outside of flapper valve
84 and bag 80 is particulate filter 72 for filtering out larger
particles. The area, room or aircraft air enters at 86. The tube
58 may be broken at 58' as shown at 88 in Figure 8 or the tube 58
may be pulled off entrance member 86.
When the lanyard is pulled down disengaging it by
handle 64 air through 58 fills bag 80 and expands filter 72 as
shown in Figure 4. The user as shown in Figure 5, breaths air
from tube 58 through passageways B, C, D and E and from the cabin
air through valve 84.
The user breaths air in through the oral-nasal mask 1
and exhales into the mask out through one-way valves 90.
The wet chemical air purifier 14, i8 a multichambered
assembly of chemicals and filter media, designed to effectively
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remove the critical levels of harmful, noxious gases and smoke
fror" the atmospheric air coming through particle filter 72 and
one or more one-way valves 84 in the plastic non-porous plastic
breather bag 84. The ai.r fron~the c:abin coming through valve 84
first passes through rigid purifier structure and filter 100. The
material making up filter 100 is a combination of ~.etal or
plastic screen, various filtering media common in the art and a
hydrophobic porous membrane to enclose the wet filter. In the
first chamber 110 is defied by a porous plastic container 112
that allows gases to pass through from filter 100 through filter
120 but keep the wet chemical within container 112. The gas iB
scrubbed as it passes through container 112. Acid gases are
neturalized in container 112 containing wet base materials. The
gases are neutralized before they pass through filter 120 and on
through the second chamber 130. Chamber 130 catalyzes CO to CO2,
by passing the gas stream throuyh a catalyst such as hopcalite, a
mixed metal oxide to provide breathable air at F. The air
purifier 14, consists of a container 112 which contains a sac 113
to store the wet base materials until activated by pulling
actuator, 64. The wet chemical air purifier 14, is comp~.etely
enclosed and seals the active chemical agents 16 within the
container 112 and sac 113 from the atmosphere. The chemical may
be both wet and/or dry when activated for use.
The chemical portion of the air purifier in container
112 and stored in sac 113, is actuated by the pull on handle 64
relative to lower cap 66 that pulls cord 150. The cord pulls air
sac 113 between rollers 152 and 154 to rupture sac 113 and
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132680~
disp~ace chemical agents 16 into container 112, as described
hereinafter. The chemical E~c~rtion of the air purifier in
container 112, has two parts, wet and dry which are mixed at the
time of actuation, to pcovide effective neutralizing solution for
wet filtration of the noxious and toxic gases as they pass
through the filter before moving on through the dry filter
portion of the air purifier 14.
As ill~strated in Figure 4, the air purifier 14, rests
partially in the interior 5, of the oral nasal mask 1, while in
storage, prior to deployment. In this state, cord 150 is
attached to handle 64 and one end of the inactivated container
112. The other end of container 112 may be connected to filter
100. The opposing end of the pull cord lS0 when pulled downward
a8 shown in Pigure 10, pU118 the sac 113 storing the liquid
component of the purifier. The end of the pull cord lS0 is
attached to the sac 113 within the air purifier container 112. As
the pas~enger pulls the handle 64, releasing the purifier shell
66 holding the air purifier 14, to deploy the oral nasal mask 1,
the tension on the cord 15, cau~es rupture of the wet sac 112,
releasing the wet chemical into the surrounding dry chemical
agent 162. As the user or pas~enger continues to pull on the
handle to pull on the lanyard 60 to release air from the air
craft storage into the air breather bag 80. The cord lS0 will
again be pulled to ensure the breaking of sac 113 in container
112 when the user i6 preparing ~he mask 1 for deployment. The
relea~e of wet chemical 164, whi-ch may be water solutions of
various alkaline hydroxides or similar base solutions, into the
dry chemical I62 which may be a mixture of metal hydroxides, or
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metal oxides, fully actuates the wet chemical air purifier ~n~
filt~ring systen,.
The ~ircraft eri,ergency air can enter the air purifier
14, through the air tube 58 throug~ entry tube 86 through passage
166 and 168 into chamber 110 and through chamber130,and through
tube 74 into the ~ask 1. A one-way valve only allowing air to
pass into compartment 166 from entr~ &6. At each stage the
elements are sealed to require passage of air in tbe desired
direction. The fresh, breathable air from the bottled air or
aircrat'c:enlergency air source enters the air tube 58 from the
aircraft supply system or storage means. Because the fresh,
breathab~e air lo~ the bott~ed air or aircraft's emergency air
source is non-contan,inated, it does not react with the chemicals
in filter 112 as it proceeds from tube 58 into bag 80, adding to
its expanded shape and then filter 100 in the air purifier 14.
~rom the filter, the fresh, breathable air passes along a path
shown by arrows D and E and enters the oral-nasal mask tube 74
which passes the alr into the oral-nasal mask 1, where it is
inhaled by the user or passenger.
A1BO attached to the air purifier 14, is an atmospheric
valve 84 or additiohal valves within filter 72. The valve 84 is
open to the atmosphere in the cabin allowing the contaminated air
into the air purifier through filter 100. The area, roon or ccbin
air passes through the first chamber 110 and the second chamber
130 and out through tube 74 into the mask 1.
The ~ser can breath both bottled air or aircraft supply
air and purifiec, area, room or cabin air in a percentage governed
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~" ~y the pressure of the aircraft supply air and the design
pressure of the valve 84 for example 60% bottled air or aircraft
sup~ly air and 40% area, room or cabin air. In the case of rapid
decompression of an aircraft, the user's air is substantially
provided by the aircraft supply.
The valve assembly 84 may be redesigned in another
embodiment so that the va~ve ~4 ~ remain ~normall~ closed~,
blocking the flow of the contaminated air from the cabin into the
wet chemical air purifier 14, until the internal pres~e of air
from the bottled air or aircraft supply system, is reduced below
a design pressure or the ambient pre~sure of the area, room or
cabin. This reduction would result from reduced flow through the
air tube 58, or increased flow demand by the user or passenger.
The internal pressure within the air purifier caused by the flow
of fresh, breathable air into the air purifier 14, ~ia the air
tube 58, may also act to force the closure of the valve 84
(deperJding on the design feature~), until the flow of fresh,
breatha~le air vla the air tube 58, ceases. The valve as~embly
58, may be a simple flapper valve well known in the art.
The air tube 58, has a breakpoint or may be pulled off
the entrance connection, where the air tube is ea~ily separated
thereby disconnecting the passenger from the aircraft's emergency
air source and giving the passenger the mobility necessary to
e~cape the aircraft. Upon disconnection of the air tube, the
entrance into the air purifier is expo~ed to the contaminated
atmospheric air thereby allowing additional contan!inated, cabin
air into the air purifier. Because the contaminated air contains
smoke, toxic gases and noxious gases, the wet and dry chemical
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materials in the air purifier reacts with and removes the sn,oke,
toxic gases, and noxious gas fron, the contaminated air thereby
rendering the air fit to breath. ~he purified air is then pulled
through the oral-nasal mask tube by the force of the passenger
inhaling from the oral-nasal mask 1, such that the passenger can
temporaril~ conti~ue to breath puriied, breathable air despite
the disconnection of the air tube 58, from the bottled or
aircraft's emergency air source.
In the event the user or passenger neglects to remove
or break the air tube, to afford the user or passenger's escape
from the area, room or aircraft and the bottled air or aircraft's
emergency air source becomes depleted, the respiratory system,
will always auto~atically deliver fresh, breathable air to the
user or passenger depite the air source depletion. The
respiratory system 12, accomplishes this using the flapper valve
84 attached to the breather bag. When the user or passenger
inhales against the depleted emergency air souIce, a VflCUUm iS
created in the interior of chambers 110 and 130 within the air
purifier 14. In an attempt to equalize internal pressures, the
higher pressured air in the area, room or cabin moves through the
filter 100 toward the lower pressured air in the air purifier 14.
The force of the higher pressured area, room or cabin air moving
into the air purifier 14, lifts the flapper valve 84, to the open
position thereby allowing cabin air into the air purifier to be
cleansed by the chemical material prior to delivery to the user
or passenger's mouth and nose, via the oral-nasal mask 1.
The interior 5, of the oral-nasal mask 1 is sterilized
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prio~ to u~ of the r~sEi r~tory system 12, to E~rc ll~ote
cleanliness. The air purifier 14, is ~haped to engage against
the edges 7 and 7' of the oral-nasal mask 1, to seal the interior
S of the oral-nasal mask 1, and to ~rev~nt the ora1-nasa~ n ~k 1
from losing its sterility prior to use by the passenger. The
user or passenger breathes air in through tube 74 and exhaust
air out flapper valves 90.
The hood 28, is folded and attached on the exterior,
near the apex, of the cup shaped oral-nasal ~ask 1 below cup 70,
see Figure 6, in the respiratory system's storage state, prior to
deployment. The upper cap 70 i8 positioned over the hood 28. The
lens 29 may be flexible and generally curved to lay flat against
the exterior of the mask 1 or in a folded position jUBt
underneath the folded hood 28.
A hood tab 30, i~ attached to the hood 28, to allow the
u6er or passenger to quickly grab or,e tab as shown in Figure ~ or
more tabs in at least one hand to pull outward in order to PE~
of the upper cap in the direction of arro~ H a~ ~hown in Figure
7. The hood is then pulled as ~hown by arrow G off of the oral-
nasal mask 1, and over the user's or passenger's head 11 as shown
in Figure 7. The hood tab i~ conspicuously positioned
substantially in front of the wearer's eyes to promote awareness
of the availability of the snloke hood attached to the oral nasal
mask 1. When propeely placed, the hood 28, covers the
passenger's entire head and neck area 31 and generally over the
shoulders. The lens 29 is positioned substantially in front of
the user'~ or passenger's eyes. The front 32, of the hood 28,
may include a short slit to allo~ the air tube 58, to run from
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~he lower cup of the air purifier 14, to the bottled air or
aircraft's emergency air source or it may extend out from under
the bottom of the hood as shown in Figure 7.
The lens 29, may be formulated of Rapton polymer and is
transparent to promote visibility in the presence of dense smoke.
The instant invention has been shown and described
herein in what is considered to be the most practical and
preferred embodiment. it is recognized, however, that departures
may be made therefrom within the scope of the invention and that
obvious modifications will occur to a person skilled in the art.
TM-Trade-Mark
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