WO2019207304A1 - A breathing apparatus - Google Patents
A breathing apparatus Download PDFInfo
- Publication number
- WO2019207304A1 WO2019207304A1 PCT/GB2019/051148 GB2019051148W WO2019207304A1 WO 2019207304 A1 WO2019207304 A1 WO 2019207304A1 GB 2019051148 W GB2019051148 W GB 2019051148W WO 2019207304 A1 WO2019207304 A1 WO 2019207304A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- wearer
- face
- breathing apparatus
- mask
- hood
- Prior art date
Links
Classifications
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- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
- A62B17/00—Protective clothing affording protection against heat or harmful chemical agents or for use at high altitudes
- A62B17/04—Hoods
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- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
- A62B17/00—Protective clothing affording protection against heat or harmful chemical agents or for use at high altitudes
- A62B17/006—Protective clothing affording protection against heat or harmful chemical agents or for use at high altitudes against contamination from chemicals, toxic or hostile environments; ABC suits
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- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
- A62B18/00—Breathing masks or helmets, e.g. affording protection against chemical agents or for use at high altitudes or incorporating a pump or compressor for reducing the inhalation effort
- A62B18/003—Breathing masks or helmets, e.g. affording protection against chemical agents or for use at high altitudes or incorporating a pump or compressor for reducing the inhalation effort having means for creating a fresh air curtain
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- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
- A62B18/00—Breathing masks or helmets, e.g. affording protection against chemical agents or for use at high altitudes or incorporating a pump or compressor for reducing the inhalation effort
- A62B18/02—Masks
Definitions
- the present invention relates to a breathing apparatus. More specifically, the present invention relates to a breathing apparatus for use in a contaminated environment.
- Breathing apparatuses are known in the art for use in environments where the ambient atmosphere contains, or may contain, noxious gases or airborne particles that may injure a person if inhaled.
- Such breathing apparatuses can include full face respirators that have a seal which extends around a wearer’s face and a visor for the wearer to see through.
- Such respirators seal the wearer’s eyes, nose, and mouth from the atmosphere but leave the periphery of the wearer’s face and the back of the wearer’s head exposed to the contaminated environment.
- some breathing apparatuses comprise a hood extending from the respirator which only covers a wearer’s nose and mouth, whilst the hood fully encloses the wearer’s head.
- the hood comprises a neck seal for sealing the wearer’s head from the contaminated environment.
- the seal(s) formed by breathing apparatuses against a wearer are critical to the performance of the apparatus in a contaminated environment, i.e. the better the seal that is formed against the wearer, the less ingress of harmful particles from the contaminated environment into the breathing apparatus that occurs which results in the fewer harmful particles being inhaled by the wearer.
- known breathing apparatuses suffer from the disadvantage that the seals are not formed sufficiently and so are not effective.
- a breathing apparatus for use in a contaminated environment, the apparatus comprising a face mask comprising an oro- nasal mask configured to surround a wearer’s nose and mouth, the oro-nasal mask having an inner seal extending about a periphery of the oro-nasal mask and configured to abut a wearer’s face around a wearer’s nose and mouth; and a visor connected to the oro-nasal mask; a hood comprising: a neck opening through which a wearer’s head is insertable; and a face opening; wherein the face mask is disposed within the face opening and the face opening of the hood is sealed around the face mask; and a secondary seal having a central opening, the secondary seal being configured abut the perimeter of a wearer’s face such that a closed space is defined between the face mask and the secondary seal when the breathing apparatus is secured to a wearer’s head.
- the secondary seal may extend from an inner surface of the hood.
- the secondary seal may comprise at least one hole configured to allow exhaled air to leak from the closed space into the hood.
- the face mask may further comprise an upper mask portion configured to extend around the visor and surround a wearer’s eyes.
- the upper mask portion comprises an outer seal configured to abut a wearer’s face around the eyes together with the oro-nasal mask.
- the upper mask portion may be integrally formed with the oro-nasal mask.
- the outer seal of the upper mask portion is integrally formed with the inner seal of the oro-nasal mask.
- the face mask is configured to abut a wearer’s face when a wearer’s face is moved horizontally through the opening in the secondary seal.
- the inner seal of the oro-nasal mask may comprise a resiliently deformable top portion which is configured to abut a wearer’s nasal ridge before the rest of the inner seal abuts a wearer’s face when the breathing apparatus is donned.
- the breathing apparatus further comprises a harness for securing the face mask to a wearer’s face.
- the face mask may be securable to a wearer’s face by the tightenable harness.
- the secondary seal may extend from the face mask.
- the secondary seal is configured to abut a wearer’s face when the face mask is moved along a wearer’s face from the forehead towards the chin.
- the secondary seal maybe configured to abut around the periphery of a wearer’s face and at least with the underside of a wearer’s chin and a wearer’s forehead.
- the secondary seal may be configured such that when the face mask is secured to a wearer’s face the secondary seal abuts a wearer’s face further back on a wearer’s forehead than on the underside of a wearer’s chin.
- the inner seal of the oro-nasal mask is configured to abut a wearer’s face on a wearer’s chin below the lower lip.
- the oro-nasal mask may comprise an exhalation duct that is configured to vent air exhaled by a wearer into the hood outside of the face mask.
- the exhalation duct is configured to vent air exhaled by a wearer into the hood outside of the secondary seal.
- the exhalation duct may be configured to vent air exhaled by a wearer into the hood inside of the secondary seal.
- the visor maybe connected proximate to a front portion of the oro-nasal mask at a point distal to a wearer’s face when the breathing apparatus is donned. This means that more of the oro-nasal mask is behind the visor so that there exists a larger area for a breathable air supply means to be connected to the face mask. The larger the area the larger the fluid conduits can be which decreases resistance to a wearer’s inhalation.
- the hood may comprise a handle configured to aid a wearer’s in deploying the hood over their head.
- the hood may comprise a neck seal configured to abut around the neck of a wearer when the hood is deployed.
- the breathing apparatus may further comprise a breathable air supply means fluidly connected with the face mask.
- the breathable air supply means may comprise a clean air canister fluidly connected to the respirator.
- the breathable air supply means may comprise an air filter.
- the air filter is fluidly connected to the respirator via a hose.
- the hose may comprise two outlets configured to direct breathable air to opposite sides of the visor.
- the hose may have a cross-section configured to remain at least partially open when folded back on itself.
- the air filter may be secured to a bib section of the hood which is configured to at least partially cover a wearer’s chest such that the air filter is configured to abut a wearer’s chest.
- a breathing apparatus for use in a contaminated environment, the apparatus comprising a face mask comprising: an oro-nasal mask configured to surround a wearer’s nose and mouth, the oro-nasal mask having an inner seal extending about a periphery of the oro- nasal mask and configured to abut a wearer’s face around a wearer’s nose and mouth; a visor connected to the oro-nasal mask; and an upper mask portion configured to extend around the visor and surround a wearer’s eyes; a hood comprising: a neck opening through which a wearer’s head is insertable; and a face opening; wherein the face mask is disposed within the face opening and the face opening of the hood is sealed around the face mask; and the oro-nasal mask further comprising an exhalation duct configured to vent air exhaled by a user into the hood outside of the face mask.
- the breathing apparatus may further comprise a secondary seal having a central opening, the secondary seal being configured to abut the perimeter of a wearer’s face such that a closed space is defined between the face mask and the secondary seal when the breathing apparatus is secured to a wearer’s head.
- the secondary seal may comprise at least one hole configured to allow exhaled air to leak from the closed space into the hood.
- the secondary seal may extend from an inner surface of the hood.
- the upper mask portion comprises an outer seal configured to abut a wearer’s face around the eyes together with the oro-nasal mask.
- the upper mask portion may be integrally formed with the oro-nasal mask.
- the outer seal of the upper mask portion may be integrally formed with the inner seal of the oro-nasal mask.
- the face mask maybe configured to abut a wearer’s face when a wearer’s face is moved horizontally through the opening in the secondary seal.
- the inner seal of the oro-nasal mask may comprise a resiliently deformable top portion which is configured to abut a wearer’s nasal ridge before the rest of the inner seal abuts a wearer’s face when the breathing apparatus is donned.
- the breathing apparatus may further comprise a harness for securing the face mask to a wearer’s face.
- the face mask may be securable to a wearer’s face by the adjustable harness.
- the secondary seal may extend from the face mask.
- the secondary seal is configured to abut a wearer’s face when the face mask is moved along a wearer’s face from the forehead towards the chin.
- the secondary seal maybe configured to abut around the periphery of a wearer’s face and at least with the underside of a wearer’s chin and a wearer’s forehead.
- the secondary seal may be configured such that when the face mask is secured to a wearer’s face the secondary seal abuts a wearer’s face further back on a wearer’s forehead than on the underside of a wearer’s chin.
- the inner seal of the oro-nasal mask may be configured to abut a wearer’s face on a wearer’s chin below the lower lip.
- the exhalation duct may be configured to vent air exhaled by a wearer into the hood outside of the secondary seal.
- the exhalation duct maybe configured to vent air exhaled by a wearer into the hood inside of the secondary seal.
- the visor may be connected proximate to a front portion of the oro-nasal mask at a point distal to a wearer’s face when the breathing apparatus is donned.
- the hood may comprise a gripping means configured to aid a wearer’s in deploying the hood over their head.
- the hood may comprise a neck seal configured to abut around the neck of a wearer when the hood is deployed.
- the breathing apparatus may further comprise a breathable air supply means fluidly connected with the face mask.
- the breathable air supply means may comprise a clean air canister fluidly connected to the respirator.
- the breathable air supply means may comprise an air filter.
- the air filter may be fluidly connected to the respirator via a hose.
- the hose may comprise two outlets configured to direct breathable air to opposite sides of the visor.
- the hose may have a cross-section configured to remain at least partially open when folded back on itself.
- the air filter may be secured to a bib section of the hood which is configured to at least partially cover a wearer’s chest such that the air filter is configured to abut a wearer’s chest.
- the breathable air supply means may be hinged attached to the face mask.
- Fig. 1 shows a side view of a first embodiment of a breathing apparatus secured to a wearer’s head with a portion of a hood cut away;
- Fig. 2 shows a front view of the breathing apparatus of Fig.i with the hood deployed over the wearer’s head;
- Fig. 3 shows a side view of a second embodiment of a breathing apparatus secured to a wearer’s head with a portion of a hood cut away;
- Fig. 4 shows a front view of the breathing apparatus of Fig. 3 with the hood deployed over the wearer’s head;
- Fig. 5 shows a side view of a third embodiment of the breathing apparatus secured to a wearer’s head with a portion of a hood cut away;
- Fig. 6 shows a rear view of a breathing apparatus in its stored configuration
- Fig. 7 shows a side view of a fourth embodiment of a breathing apparatus secured to a wearer’s head with a portion of a hood cut away
- Fig. 8 shows a side view of a fifth embodiment of a breathing apparatus secured to a wearer’s head with a portion of a hood cut away;
- Fig. 9 shows a front perspective view of a sixth embodiment of a breathing apparatus with a portion of a hood cut away;
- Fig. 10 shows a rear perspective view of the breathing apparatus of Fig. 9 with a portion of a hood cut away;
- Fig. 11 show a cross-sectional side view of the breathing apparatus of Fig. 9 with a portion of the hood cut away;
- Fig. 12 shows a side view of the breathing apparatus of Fig. 9 with a portion of a hood cut away;
- Fig. 13 shows a front view of the breathing apparatus of Fig. 9 with a portion of the hood cut away;
- Fig. 14 shows a side view of a sixth embodiment of a breathing apparatus secured to a wearer’s head with a portion of the hood cut away;
- Fig. isshows a schematic side view of a harness used to secure a breathing apparatus to a wearer’s head;
- Fig. 16 shows a schematic side view of a harness used to secure a breathing apparatus to a wearer’s head- Detailed Description
- a breathing apparatus 1 for use in a contaminated environment Referring to Figs. 1 and 2, a breathing apparatus 1 for use in a contaminated environment
- a contaminated environment exists where the ambient atmosphere contains noxious gases or airborne particles that may injure a person if inhaled. In some cases an environment may be considered to be contaminated when there are as little as 2,000 part per million of the noxious gas or harmful particle. Thus, it is important that the breathing apparatus 1 can be put on in the minimum amount of time when a exposure to a noxious gas and/or harmful particle occurs.
- the breathing apparatus 1 comprises a face mask 2.
- the face mask 2 is configured to fit around a wearer’s face when the breathing apparatus 1 is donned.
- the face mask 2 comprises an oro-nasal mask 3 that is configured to surround a wearer’s nose and mouth.
- the oro-nasal mask 3 may comprise a hollow body 4, which may be an outer shell 4having an open end 5 which allows a wearer to place their nose and mouth into the oro-nasal mask 3.
- the outer shell 4 is configured to house components of the breathing apparatus 1, such as, but not limited to, valves (not shown), as will be discussed in more detail hereinafter.
- the outer shell 4 may be rigid and formed from, for example, but not limited to,....
- the oro-nasal mask 3 further comprises an inner seal 6 which extends about the periphery of the oro-nasal mask 3.
- the inner seal 6 may extend around the periphery of the hollow body 4 or may extend from within the shell 4 and out of the open end.
- the inner seal 6 is an inner face mask seal. That is, the inner seal 6 is configured to abut a wearer’s face around a wearer’s nose and mouth.
- the inner seal 6 is configured to abut a wearer’s face in order to attempt to form a primary seal.
- the inner seal 6 of the oro-nasal mask 3 is configured to prevent or at least reduce the amount of noxious gases and/ or harmful particles entering a wearer’s respiratory system when the breathing apparatus 1 is donned in a contaminated environment.
- the inner seal 6 of the oro-nasal mask 3 is configured to abut a wearer’s face on the wearer’s chin below the lower lip and on the wearer’s nasal ridge.
- the oro-nasal mask 3 may not comprise an outer shell 4 and may instead be formed of a single element which surrounds a wearer’s nose and mouth and comprises the inner seal 6 extending about the periphery of its open end 5. Furthermore, a top portion 6a of the inner seal 6 of the oro-nasal mask 3 in the region of the wearer’s nasal ridge may comprise a bellows arrangement. That is, the top of the inner seal 6 which abuts a wearer’s nasal ridge when the breathing apparatus is donned may be resiliently deformable.
- the resiliently deformable top portion 6a may be configured to abut a wearer’s nasal ridge before the rest of the inner seal 6 abuts a wearer’s face when the breathing apparatus 1 is donned.
- the top of the inner seal 6 is configured to extend away from the hollow body 4 of the oro-nasal mask 3 before the breathing apparatus 1 is donned. Therefore, during the donning of the breathing apparatus 1, which is described in more detail hereinafter, the time taken for the inner seal 6 of the oro-nasal mask 3 to form a seal around a wearer’s nose and mouth is minimised. Thus, there is a small chance of harmful substances from the contaminated environment entering a wearer’s respiratory system.
- the face mask 2 further comprises a visor 7 which is connected to the oro-nasal mask 3.
- the visor 7 is connected to the body 4 of the oro-nasal mask 3.
- the visor 7 is sealed to the oro-nasal mask 3 in order to prevent or at least reduce the amount of noxious gases or harmful particles that can pass between the oro-nasal mask 3 and the visor 7. This helps to prevent the noxious gases or harmful particles coming into contact with a wearer’s eyes.
- the visor 7 maybe curved to partially match the curvature of a wearer’s face or maybe a flat sheet.
- the visor 7 is formed of a transparent material. That is, the visor 7 maybe formed from, for example, but not limited to,....
- the visor 7 may comprise a position indicating means 8 as shown in Fig. 2.
- the position indicating means 8 is configured to provide a reference point for a wearer to indicate whether they have donned and positioned the breathing apparatus 1 correctly in order to prevent or at least reduce the amount of noxious gases and/or harmful particles that enter that breathing apparatus 1 and/ or the wearer’s body.
- the position indicating means 8 comprises two circles 9 which indicate where a wearer’s eyes should be positioned in the breathing apparatus 1 when the breathing apparatus 1 is worn properly, as will be discussed in more detail hereinafter.
- the circles 9 may be formed by a groove in the visor 7 or by a layer of, for example, but not limited to, ink or paint.
- the circles 9 are formed by a circumferential curve which is hollow. That is, the middle of the circles 9 do not contain any ink or paint so that the wearer’s vision is not obscured.
- other shapes such as, for example, but not limited to, crosses or dots may be used.
- the visor 7 is connected proximate to the front portion of the hollow body 4 of the oro-nasal mask 3, as shown in Fig. 5. That is, the visor 7 is mounted on the body 4 of the oro-nasal mask 3 at a point distal to a wearer’s face when the breathing apparatus 1 is donned.
- the visor 7 is preferably mounted on the hollow body 4 of the oro-nasal mask 3 in the region of the tip of a wearer’s nose instead of in the region of the nasal ridge of a wearer’s nose. Therefore, there is more space behind the visor 7 for the placement of outlets 24 for the direction of breathable air towards the visor 7, as will be explained in more detail hereinafter.
- the breathing apparatus 1 further comprises a hood 10 that is configured to cover a wearer’s head when the breathing apparatus l is worn properly.
- the hood 10 comprises a neck opening 11 through which a wearer’s head is insertable.
- the hood 10 Before the breathing apparatus 1 is required it is usually stored in a bag that can be carried by a person in an environment in which contamination of the surroundings is possible.
- the hood 10 may be rolled up so that the neck opening n surrounds the face mask 2.
- the hood 10 is rolled up such that the secondary seal 16 surrounds the face mask 2 and faces the person about to don the breathing apparatus l.
- a wearer can place their face directly against the face mask 2 through the secondary seal 16 before deploying the hood io. This minimises the amount of time required to don the breathing apparatus l from the realisation that the environment is contaminated and can be vital is protecting a wearer from the harmful environment.
- An example of an alternative embodiment of the breathing apparatus is shown in Fig. 6 in the storage configuration, as will be described in more detail hereinafter.
- the hood io may further comprise a gripping means 12, shown in Fig. l, such as a handle, toggle, or pull chord, that is configured to aid a wearer in grasping the hood io and pulling it over their head.
- the grasping means 12 may be placed close to the bottom of the hood 10 next to the neck opening 11 so that a wearer can more easily fully deploy the whole hood 10 over their head.
- the hood 10 may also further comprise a neck seal 13 extending about the edge of the neck opening 11.
- the neck seal 13 is configured to abut against a wearer’s neck once the hood 10 has been pulled over a wearer’s head.
- the neck seal 13 is configured to reduce the amount of noxious gases and/ or harmful particles that enter the hood 10 once the hood 10 has been deployed.
- the neck opening 11, or at least a portion of the hood 10 proximate the hood neck opening 11 is elasticated in an attempt to prevent the ingress of harmful substances in the
- the hood 10 comprises a face opening 14.
- the face opening 14 of the hood 10 is configured to receive the face mask 2 of the breathing apparatus 1. That is, the face mask 2 is disposed within the face opening 14.
- the periphery of the face opening 14 of the hood 10 is sealed around the face mask 2.
- noxious gases and/ or harmful particles are prevented from entering the breathing apparatus 1 through the face opening 14 of the hood 10.
- the face opening 14 is sealed against the oro-nasal mask 3, preferably against the hollow body or outer shell 4, and the visor 7.
- the face mask 2 may be sealed to the face opening 14 of the hood 10 by adhesive, such as, but not limited to,..., or by other means, such as,....
- the breathing apparatus 1 further comprises a secondary seal 16 that comprises a central opening 17.
- the central opening 17 is configured to allow a wearer to place their face through the secondary seal 16.
- the secondary seal 16 is configured to abut the perimeter of a wearer’s face.
- the secondary seal 16 abuts a wearer’s face closer to a wearer’s ear than the inner seal 6 of the face mask 2.
- the secondary seal 16 is configured to abut at least with the underside of a wearer’s chin and with a wearer’s forehead. Therefore, the secondary seal may be configured such that when the face mask 2 abuts a wearer’s face, the secondary seal 16 is inclined to the vertical.
- the portion of the secondary seal 16 which abuts a wearer’s forehead is located further in the horizontal direction from a wearer’s nose than the portion of the secondary seal 16 which abuts a wearer’s chin.
- the secondary seal 16 extends from an inner surface of the hood 10.
- a closed space 18 is defined between the face mask 2 and the secondary seal 16 when the breathing apparatus 1 is donned by a wearer.
- the closed space 18 between the inner seal 6 and the secondary seal 16 is configured to form a space which is predominantly filled with breathable air in order to prevent or at least reduce the amount of noxious gases and/or harmful particles that are present within the portion of the hood 10 in which a wearer’s face is located so that the contact between the noxious gases and/or harmful particles and a wearer’s eyes, nose, and mouth, is reduced.
- the breathing apparatus 1 further comprises a harness 20 for securing the face mask 2 to a wearer’s face.
- the harness 20 is configured to be placed over a wearer’s head so that the harness 20 extends from the face mask 2 to the back of a wearer’s head.
- the harness 20 is adjustable. That is, the harness 20 can be tightened once it has been placed over the head of a wearer such that any person, no matter what the size of their head, can use the breathing apparatus 1. The harness 20 is tightened until the face mask 2 is secured to a wearer’s face.
- the tightening of the harness 20 moves the face mask 2 of the breathing apparatus l towards a wearer’s face, specifically, a wearer’s nose and mouth, and force the inner seal 6 against the wearer’s face so that a primary seal is formed to prevent noxious gases and/or harmful particles entering a wearer’s respiratory system.
- the harness 20 may extend on the inside of the hood to such that the harness 20 must be placed around a wearer’s head and tightened before the hood 10 is pulled down over a wearer’s head.
- the harness 20 may extend on the outside of the hood 10 such that the hood 10 must be pulled down over a wearer’s head before the harness is placed around a wearer’s head and tightened.
- the harness 20 may be within the material of the hood 10 such that in the same movement as deploying the hood 10 the harness is placed around a wearer’s head. The harness 20 can then be adjusted to the size of a wearer’s head.
- the harness 20 may be, for example, but not limited to, adjustable straps.
- the harness 20 may comprises a strap extending from the mouth portion of the face mask 2.
- the harness 20 may be designed so that a wearer must pull a strap (not shown) to tighten the harness 20 to secure the breathing apparatus 1 to their face.
- the harness 20 may be designed so that the at least one strap is either pulled in a direction that a wearer is facing or is pulled behind a wearer’s head.
- the breathing apparatus 1 may further comprise a breathable air supply means 22.
- the breathable air supply means 22 is configured to provide breathable air to a wearer of the breathing apparatus 1 so that a wearer does not breathe in noxious gases and/ or harmful particles that are present in a contaminated environment.
- the breathable air supply means 22 is fluidly connected to the face mask 2.
- the breathable air supply means 22 may be fluidly connected to the face mask 2 by, for example, a hose 23. As illustrated in the drawings, the hose 23 may be located outside of the hood 10.
- the hose 23 may extend within the hood 10 when the breathing apparatus 1 is donned. In such an embodiment, the hose 23 may pass through the secondary seal
- the hose 23 may be folded back on itself when the breathing apparatus is stored in its bag (not shown) before use. Therefore, the hose 23 has a cross-section that is configured to remain at least partially open when the hose 23 is folded.
- the cross-section may comprise a diametrically extending element that extends perpendicularly to the fold line which prevents that cross-section of the tube from closing completely when the hose 23 is folded for storing. This enables a flow of breathable air to the face mask 2 to be provided instantly when the breathing apparatus 1 is removed from the bag because there is no need for a wearer to check that the hose 23 is properly unfolded and that there is no blockage of the flow of breathable air.
- the hose 23 is fluidly connected, in the present embodiment, to two outlets 24 that deliver breathable air to the face mask 2, although it will be understood that the number of outlets may vary.
- the placement of the visor 7 close to the front of the oro- nasal mask 3 allows the hose 23 or ducting to fit into the oro-nasal mask 3 without compromising the cross-sectional area of the hose 23 and in turn raising the resistance to breathing experienced during use.
- the hose 23 may comprise a single duct which branches into two ducts proximate to the face mask 2.
- the outlets 24 are configured to direct breathable air to opposite sides of the visor 7 through the oro-nasal mask 3. Therefore, the breathable air can be used to“de-mist” the visor 7 to prevent the visor 7 fogging up and obscuring a wearer’s vision.
- the outlets 24 may direct breathable air towards the position indicating means 8 on the visor 7 or any other portion of the visor 7.
- the hose 23 may comprise two ducts which communicate fluidly with one outlet 24 each.
- the breathable air supply means 22 comprises an air filter 26.
- a one-way valve may be present such that a wearer of the breathing apparatus may draw air through the filter 26 to be breathed in but cannot breathe air out through the filter 26.
- the breathable air supply means 22 may comprise a clean air canister (not shown). The flow of breathable air from the clean air canister may be started automatically upon removal of the breathing apparatus 1 from the bag, as is known in the art.
- the hood 10 comprises a bib section 28.
- the bib section 28 is a part of the hood 10 which extends down from the face mask 2 at least partially over a wearer’s chest when the breathing apparatus 1 is worn properly and the hood 10 is deployed.
- the breathable air supply means 22, the air filter 26 in the embodiment illustrates, is mounted on the bib portion 28 such that the breathable air supply means 22 abuts a wearer’s chest. Therefore, the weight of the breathable air supply means 22 is supported by a wearer’s chest.
- the air filter 26 maybe connected to the face mask 2 via a hinge arrangement 29.
- the hinge arrangement 29 allows the air filter 26 to be stored in its stowed position within the face mask 2 when the breathing apparatus 1 is stored in its bag (not shown). Therefore, when donning the breathing apparatus 1, the air filter 26 must be rotated about the hinge arrangement to remove the air filter 26 from the face mask 2 to place the air filter 26 in its extended position before a wearer can place their face into the face mask 2.
- the arrangement 29 comprises a hinged hose 23 with a coupling 29a.
- the hose 23 is split into two. One end of a first portion of the hose 23 is connected to the air filter 26 and the other end of the first portion is connected to one half of the coupling. One end of a second portion of the hose is connected to the other half of the coupling and the other end of the second portion is connected to the face mask 2.
- the coupling is in a hinged open position when the air filter 26 is stowed in the face mask 2 and when the air filter 26 is rotated into its extended position the coupling is hinged closed to form an air tight fluid conduit for breathable air to flow form the air filter 26 into the face mask 2.
- the hose 23 may be a flexible tube connecting the air filter 26 and the face mask 2 that can be bent so that the air filter can be stowed in the face mask 2.
- the air filter 26 may be connected to a separate hinge.
- the breathable air supply means 22 may be provided on the face mask 2. That is, the breathable air supply means 22 may be mounted on the hollow body or outer shell 4 of the oro-nasal mask 3. In such embodiments, the breathable air supply means 22 maybe a filter. When a person becomes aware that the environment they are in has become contaminated, they open the bag (not shown) in which the breathing apparatus 1 is stored and remove the breathing apparatus 1 from the bag. As the hood to is rolled up, the neck opening 11 and secondary seal 16 surround the periphery of the face mask 2. The air filter 26 may need to be removed from the face mask 2 by rotating it about the hinge.
- a wearer takes the breathing apparatus 1 and moves the breathing apparatus 1 in a direction from a wearer’s forehead towards a wearer’s chin.
- the secondary seal 16 may form an initial, at least partial, seal with a wearer’s face and so may prevent or at least reduce the amount of noxious gases/and or harmful particles that enter the portion of the breathing apparatus 1 in which a wearer places their face.
- the breathing apparatus 1 is moved down a wearer’s face until the top of the secondary seal 16 abuts a wearer’s forehead and the bottom of the secondary seal 16 locates underneath a wearer’s chin and the oro-nasal mask 3 is positioned roughly over a wearer’s nose and mouth.
- the resiliently deformable top portion of the inner seal 6 will abut against the nasal ridge of a wearer’s nose.
- the harness 20 is then adjusted, usually tightened, until the oro-nasal mask 3 is secured over a wearer’s nose and mouth and the top portion of the inner seal 6 is compressed.
- the oro-nasal mask 3 is drawn closer to a wearer’s face so that the inner seal 6 abuts a wearer’s face about their nose and mouth.
- the harness 20 is fully tightened, the inner seal 6 seals the nose and mouth from the contaminated
- the closed space 18 is defined between the inner seal 6 of the oro-nasal mask 3 and the secondary seal 16.
- a wearer then begins to breathe normally.
- a negative pressure is caused in the oro-nasal mask 3 and so air is drawn in through a one-way valve (not shown) from the closed space 18.
- This in turn causes a negative pressure in the closed space 18.
- a one-way valve (not shown) in the hose 23 is configured such that it opens in response to negative pressure before the secondaiy seal 16. Therefore, breathable air is drawn into the closed space 18 through the air filter 26 rather than contaminated air from outside the secondary seal 16.
- the breathable air is drawn into the closed space and is directed from the outlets 24 of the hose 23 towards the position indicating means 8 of the visor 7.
- the breathable air Once the breathable air has impinged on the visor 7 to demist the visor 7, it is drawn through the one-way valve (not shown) in the face mask 2 and breathed in by a wearer.
- the exhalant cannot exit through the one-way valve (not shown) through which it entered the oro-nasal mask 3 and so exits through a one-way outlet valve (not shown) to the atmosphere.
- a wearer may grasp the gripping means 12 and pull the hood 10 down over their head. Once the hood 10 has been fully deployed, the air filter 26 may rest upon a wearer’s chest and the neck seal 13 in the neck opening 11 may abut a wearer’s neck in order to prevent or at least reduce the amount of noxious gases and/or harmful particles entering the hood 10 of the breathing apparatus 1.
- Figs. 3 and 4 there is shown a schematic cross-sectional side view of a second embodiment of the breathing apparatus 30.
- the breathing apparatus 30 is generally the same as the embodiment of the breathing apparatus 1 described above and so features and components of the breathing apparatus 30 that are the same as the features and components of the breathing apparatus 1 will retain the same terminology and reference numerals. As the breathing apparatus 30 is generally the same as the embodiment of the breathing apparatus 1 described above, a detailed description of similar features and components will be omitted.
- the face mask 2 of the breathing apparatus 30 further comprises an upper mask portion 31.
- the upper mask portion 31 is configured to extend around the visor 7 and surrounds a wearer’s eyes. That is, the upper mask portion 31 is configured to fit around a wearer’s eyes when the breathing apparatus 30 is donned.
- the face opening 14 is sealed against the oro- nasal mask 3, preferably against the hollow body or outer shell 4, and the upper mask portion 31.
- the upper mask portion 31 comprises an outer seal 32 which is configured to abut a wearer’s face around the eyes.
- the outer seal 32 is located within the hood 10.
- the outer seal 32 of the face mask 2 is configured to prevent or at least reduce the amount of noxious gases and/ or harmful particles entering a wearer’s respiratory system or contacting a wearer’s eyes when the breathing apparatus 30 is donned in contaminated environment.
- the upper mask portion 32 is integrally formed with the oro-nasal mask 3.
- the outer seal 32 of the upper mask portion 31 is also integrally formed with the inner seal 6 of the oro-nasal mask 3.
- the secondary seal 16, shown in Fig. 3 extends from the face mask 2 instead of the inner surface of the hood 10. Therefore, in one embodiment, the breathing apparatus may be provided without the hood 10. However, it will be understood that the secondary seal 16 may extends from the inner surface of the hood 10.
- the harness 20 may comprise a strap extending from the mouth portion of the face mask 2 and a strap extending from the temple portion of the face mask 2.
- the bag When a person becomes aware that the environment they are in has become contaminated, they open the bag (not shown) storing their breathing apparatus 30 and remove the breathing apparatus 30 from the bag. As the hood 10 is rolled up, the neck opening 11 surrounds the periphery of the face mask 2 and the secondary seal 16 extends out of the neck opening 11 of the hood 10, as illustrated in Fig. 6.
- a wearer takes the breathing apparatus 30 and moves the breathing apparatus 30 in a direction from a wearer’s forehead towards a wearer’s chin.
- the secondary seal 16 forms an initial, at least partial, seal with a wearer’s face and prevents or at least reduces the amount of noxious gases/and or harmful particles that enter the portion of the breathing apparatus 30 in which a wearer places their face.
- the breathing apparatus 30 is moved down a wearer’s face until the top of the secondary seal 16 abuts a wearer’s forehead and the bottom of the secondary seal 16 locates underneath a wearer’s chin and the oro-nasal mask 3 is positioned over a wearer’s nose and mouth so that it forms a seal due to the resiliently deformable top portion of the inner seal 6 abutting against the nasal ridge of a wearer’s nose and the rest of the inner seal contacting the wearer’s face.
- the first effective seal formed is formed by the inner seal 6 of the oro-nasal mask 3 around a wearer’s nose and mouth. A wearer then passes the harness 20 over their head.
- the harness 20 is then adjusted, usually tightened, to further secure the oro-nasal mask 3 over a wearer’s nose and mouth.
- the oro-nasal mask 3 is drawn closer to a wearer’s face so that the inner seal 6 abuts a wearer’s face with greater force about their nose and mouth.
- the harness 20 is fully tightened, the top portion of the inner seal 6 seal is compressed and the nose and mouth is sealed from the contaminated environment.
- the tightening of the harness 20 also pulls the upper mask portion 31 towards the face such that the outer seal 32 contacts a wearer’s face around the wearer’s eyes.
- the closed space 18 is defined between the inner seal 6 of the oro- nasal mask 3, the outer seal 32 of the upper mask portion 31 and the secondary seal 16.
- a wearer then begins to breathe normally.
- a negative pressure is caused in the oro-nasal mask 3 and so air is drawn in through a one-way valve (not shown) from the upper mask portion 31.
- This in turn causes a negative pressure in the upper mask portion 31.
- a one-way valve (not shown) in the hose 23 is configured such that it opens in response to negative pressure before the secondary seal 16. Therefore, breathable air is drawn into the upper mask portion 31 through the air filter 26 rather than contaminated air from outside outer seal 32 or the secondary seal 16.
- the breathable air is drawn into the face mask 2 and is directed from the outlets 24 of the hose 23 towards the position indicating means 8 of the visor 7.
- the breathable air Once the breathable air has impinged on the visor 7 it is drawn through the one-way valve (not shown) in the oro-nasal mask 3 and breathed in by a wearer.
- the exhalant cannot exit through the one-way valve (not shown) through which it entered the oro-nasal mask 3 and so exits through a one-way outlet valve (not shown) to the atmosphere.
- the outlet valve may be a simple small hole.
- a wearer may grasp the gripping means 12 and pull the hood 10 down over their head. Once the hood 10 has been fully deployed, the air filter 26 will rest upon a wearer’s chest and the neck seal 13 in the neck opening 11 may abut a wearer’s neck in order to attempt to prevent noxious gases and/or harmful particles entering the hood 10 of the breathing apparatus 30.
- Fig. 5 there is shown a schematic cross-sectional side view of a third embodiment of a breathing apparatus 40.
- the breathing apparatus 40 is generally the same as the embodiment of the breathing apparatus 30 described above and so features and components of the breathing apparatus 40 that are the same as the features and components of the breathing apparatus 30 will retain the same terminology and reference numerals. As the breathing apparatus 40 is generally the same as the embodiment of the breathing apparatus 30 described above, a detailed description of similar features and components will be omitted.
- the face mask 2 of the breathing apparatus 40 comprises an oro-nasal mask 3 configured to surround a wearer’s nose and mouth and an upper mask portion 31 which extends around a visor 7 and surrounds a wearer’s eyes.
- An outer seal 32 of the upper mask portion 31 and an inner seal 6 of the oro-nasal mask 3 abut a wearer’s face around the eyes in order to form a primary seal to at least reduce the amount of noxious gases and/or harmful particles enters a wearer’s respiratory system or contacting a wearer’s eyes when the breathing apparatus 40 is donned in a contaminated environment.
- a secondary seal 16 extends from the face mask 2 and has a central opening 17 through which a wearer can place their face to fit the face mask 2 to their face when donning the breathing apparatus 40. Once a wearer’s face is placed into the face mask 2, the primary seal 6, 32 and secondary seal 16 contact a wearer’s face to act as a barrier against the contaminated environment. However, it will be understood that in the present embodiment, the secondary seal 16 may be omitted.
- a harness 20 which is connected to the face mask 2 may then be pulled over a wearer’s head and fastened such that the face mask 2 can be worn by a wearer without the wearer having to hold the face mask 2 to their face.
- a hood 10 can be extended from its bundled state in which it is stored and pulled over a wearer’s head.
- the neck opening 11 of the hood 10 maybe elasticated such that the hood 10 has a narrow portion proximate the neck opening to reduce the flow of air in and out of the hood 10.
- the breathable air supply means 22 maybe a canister of air or, as shown in Fig. 5, an air filter 26 which hinged on the face mask 2 and fluidly connected to the face mask 2 by a hose 23.
- the air filter 26 is mounted on the bib section 28 of the hood 10.
- the air filter 26 may be mounted on the oro-nasal mask 3 in front of a wearer’s mouth or two air filters 26 maybe mounted on the side of the oro-nasal mask 3; one over each cheek of the wearer.
- Air is drawn through the filter 26 and is filtered so that breathable air is directed from outlets 24 towards the position indicating means 8 of the visor 7.
- the breathable air Once the breathable air has impinged on the visor 7 and demisted the visor 7 so that a wearer can see out of the face mask 2 whilst wearing the breathing apparatus 40, it is drawn through a one- way valve (not shown) in the oro-nasal mask 3 and breathed in by a wearer.
- the one- way valve (not shown) in the filter 26 prevents moisture in the exhaled air flowing back into the filter26 and clogging the filter 26.
- the oro-nasal mask 3 further comprises an exhalation duct 41 which is configured to vent air that is exhaled by a wearer out of the oro-nasal mask 3.
- the exhalation duct 41 has an outlet 42 which is located in the hood 10 of the breathing apparatus 40 such that the air exhaled by a wearer is directed into the space within the hood 10 outside of the seals formed against a wearer’s face but inside the neck opening 11 of the hood 10.
- the outlet 42 of the exhalation duct 41 is located outside of the secondary seal 16.
- the outlet 42 of the exhalation duct 41 is located outside the primary seal formed by the inner seal 6 and the outer seal 32.
- an exhalation duct 41 extends horizontally from the side of the oro-nasal mask 3 around a wearer’s face to its outlet 42 behind the secondary seal 16.
- the duct 41 comprises a one-way valve (not shown) so that exhaled air, or any harmful gases trapped in the hood 10, cannot be breathed in through the duct 41 by the wearer.
- the carbon dioxide Due to the weight of the carbon dioxide gas in the air exhaled by the wearer, the carbon dioxide will sink towards the neck opening 11 the bottom of the hood 10 once it has exited the outlet 42 of the exhalation duct 41. Therefore, the carbon dioxide gas is not breathed back in by the user. Furthermore, by diverting the flow of exhaled air into the hood 10 instead of directly to the atmosphere, a barrier of non-harmful air can be built up between the secondary seal 16 and the neck opening 11 of the hood 10.
- the primary seal 6, 32 or secondary seal 16 are not in contact with a wearer’s face all the way around their periphery because, for example, the wearer wears glasses or has a beard, the harmful gases from the contaminated environment can be prevented from entering the closed space 18 in the face mask 2 because any leakage from the hood 10 outside the secondary seal 16 will be air exhaled by the wearer which will have extremely low concentrations, if any, of harmful substances from the contaminated atmosphere.
- a schematic cross-sectional side view of a fourth embodiment of a breathing apparatus 70 is generally the same as the embodiment of the breathing apparatus 40 described above and so features and components of the breathing apparatus 70 that are the same as features and components of the breathing apparatus 40 will retain the same terminology and reference numerals. As the breathing apparatus 70 is generally the same as the embodiment of the breathing apparatus 40 described above, a detailed description of similar features and components will be omitted.
- the exhalation duct 41 which extends from the oro-nasal mask 3, has its outlet 42 in the space 18 between the primary seal 6, 32 of the face mask 2 and the secondary seal 16. Therefore, when a wearer exhales, the exhaled air exits outside of the primary seal 6, 32 but inside of the secondary seal 16.
- the secondary seal 16 may be configured to move out of contact with a wearer’s face.
- the secondary seal 16 may move out of contact with a wearer’s face due to being configured to form a weaker seal with a wearer’s face than the primary seal 6, 32. Due to the relative high pressure in the space 18 compared to the relative low pressure outside of the secondary seal 16 but within the hood 10, the free movement of air between the space 18 and the hood 10 is restricted. In fact, the pressure differential between the exhaled air in the space 18 and the air in the hood 10 outside the secondary seal 16 results in air flow from the space 18 into the hood 10. Therefore, harmful gases are prevented from entering the face mask 3.
- the secondary seal 16 may be configured to that it remains sealed to a wearer’s face as the pressure in the space 18 increases. This may be achieved by configuring the secondary seal 18 such that it forms a stronger seal with a wearer’s face. In such an embodiment, the pressure may become sufficiently high such that it becomes difficult for a wearer to breathe out into the space. Therefore, in order to alleviate the pressure build up without the secondary seal moving out of contact with a wearer’s face, the secondary seal 18 is provided with a hole 71 configured to allow exhaled air to leak from the space 18 between the primary seal 6, 32 and the secondary seal 16 into the space in the hood 10.
- the secondary seal 16 may comprise a plurality of holes 71.
- the holes 71 may be evenly spaced around the secondary seal 16 or located in groups. It will be understood from the description above that in the embodiment illustrated in Fig. 7 does not require a hole 71 in the secondaiy seal 16 to function and that any number of holes 71 in the secondary seal 16 is optional. In the absence of a hole 71, positive air pressure in the enclosed space 18 may leak out of the enclosed space between the secondary seal 16 and a wearer’s face, as will be described in more detail hereinafter.
- the holes 71 are sized to prevent the free flow of air between the two spaces but allow air under high pressure in the space 18 to leak into the hood 10. In this way, harmful gases and/ or substances from the contaminated environment can be prevented from entering the face mask 2.
- the holes 71 may comprise one-way valves configured to only allow air flow from the space 18 into the hood 10 and prevent air flow form the hood 10 into the space 18.
- the exhaled air that is breathed out into the space 18 will pass the secondary seal 16 by moving the secondary seal 16 out of contact with a wearer’s face.
- the exhaled air in the space 18 may leak through the holes 71 in the secondary seal 16 from the space 18 into the hood 10.
- Fig. 8 there is shown a schematic cross-sectional view of a fifth embodiment of a breathing apparatus 80.
- the breathing apparatus is generally the same as the embodiment of the breathing apparatus 40 described above and so features and components of the breathing apparatus 80 that are the same as features and components of the breathing apparatus 40 will retain the same terminology and reference numerals.
- the breathing apparatus 80 is generally the same as the embodiment of the breathing apparatus 40 described above, a detailed description of similar features and components will be omitted.
- the outer seal 32 that extends about the upper mask portion 31 of the face mask 2 is omitted.
- the face mask 3 is bonded to the hood 10 and the secondary seal 16 provides a barrier between the space 18 in the face mask 3 and the space in the hood 10.
- Figs. 9 to 14 there is shown a perspective view of a sixth embodiment of a breathing apparatus 90.
- the breathing apparatus 90 is generally the same as the embodiments of the breathing apparatuses described above and so features and components of the breathing apparatus 90 will retain the same terminology and reference numerals.
- As the breathing apparatus 90 is generally the same as the embodiment of the breathing apparatuses described above, a detailed description of similar features and components will be omitted.
- the breathing apparatus 90 is for use in a contaminated environment where the atmosphere contains noxious gases or airborne particles that may injure a person if inhaled.
- the breathing apparatus 90 comprises a face mask 2.
- the face mask 2 is configured to fit around a wearer’s face when the breathing apparatus 90 is donned.
- the face mask 2 comprises an oro-nasal mask 3 that is configured to surround a wearer’s nose and mouth.
- the oro-nasal mask 3 comprises an hollow body 4 having an open end 5 which allows a wearer to place their nose and mouth into the oro-nasal mask 3.
- the hollow body 4 is connected to the breathable air supply means 22 which in this case is an air filter 26 mounted on the face mask 2.
- the filter 26 closes an installation hole 96 in the front of the oro-nasal mask 3 which is used for installing a valve which will be described in more detail below.
- the oro-nasal mask 3 comprises a hollow body 4 having an open end 5 which allows a wearer to place their nose and mouth into the oro-nasal mask 3.
- the oro-nasal mask 3 further comprises an inner seal 6 which extends about the periphery of the oro-nasal mask 3.
- the inner seal 6 forms part of the primary inner face mask seal. That is, the inner seal 6 is configured to abut a wearer’s face around a wearer’s mouth and nose.
- the inner seal 6 of the oro-nasal mask 3 is configured to prevent or at least reduce the amount of noxious gases and/ or harmful particles entering a wearer’s respiratory system when the breathing apparatus 1 is donned in a contaminated environment.
- the inner seal 6 of the oro-nasal mask 3 is configured to abut a wearer’s face on the wearer’s chin below the lower lip and on the wearer’s nasal ridge.
- the face mask 2 of the breathing apparatus 90 further comprises an upper mask portion 31 that is configured to extend around a visor 7, which is connected to the oro- nasal mask 3, and is configured to fit around a wearer’s eyes when the breathing apparatus 90 is donned.
- the upper mask portion 31 of the face mask 2 is integrally formed with the oro-nasal mask 3.
- the visor 7 is sealed against the oro-nasal mask 3 on its lower side and against the upper mask portion 31 on its remaining sides to prevent noxious gases passing into the face mask 2.
- the upper mask portion 31 of the face mask 2 comprises an outer seal 32 which is configured to abut a wearer’s face around the eyes.
- the outer seal 32 is integrally formed with the inner seal 6 of the oro-nasal mask 3 such that together they form a primary seal around a wearer’s face which when donned forms two specific sealed volumes, one around a wearer’s nose and mouth and one around a wearer’s eyes.
- the outer seal 32 of the face mask 2 is configured to prevent or at least reduce the amount of noxious gases and/ or harmful particles entering a wearer’s respiratory system or contacting a wearer’s eyes when the breathing apparatus 30 is donned in contaminated environment.
- the breathing apparatus 90 further comprises a hood 10 that is configured to cover a wearer’s head when the breathing apparatus 90 is fully donned.
- the hood 10 is shown partially removed in Figs. 9 and 10.
- Fig. 9 shows where a face opening 14 of the hood 10, which receives the face mask 2, is sealed against the face mask 2 and in this case the filter 26.
- the hood 10 maybe thermally sealed or sealed by adhesive to the face mask 2 and filter 26. Thus, noxious gases and/or harmful particles are prevented from entering the breathing apparatus 1 through the face opening 14 of the hood 10.
- the hood 10 may comprise a neck opening, gripping means, and/or neck seal (not shown).
- the breathing apparatus 90 When the breathing apparatus 90 is removed from its storage container it will be in a configuration similar to the one shown in Fig. 6, except for the fact that the breathing apparatus 90 will comprise a filter 26 mounted on the front of the face mask 2 instead of on the bib such that the hose of Fig. 6 will not be present and the filter 26 will not be stored in the area where a wearer’s head will eventually be placed.
- the face mask 2 of the breathing apparatus 90 When the face mask 2 of the breathing apparatus 90 is placed on a wearer’s face during the donning process, the inner and outer seals 6, 32 abut a wearer’s face around the eyes, nose, and mouth to create a primary seal. When the primary seal has been created, inhalation by a wearer causes a negative pressure within the oro-nasal mask 3.
- first one-way valve 91 located in the body 4 of the oro-nasal mask 3.
- one first one way valve 91 can be seen on a side face of the body 4 of the oro-nasal mask 3.
- a low pressure is created in the upper mask section 31 of the face mask 2. This low pressure draws air through the filter 26 and into the face mask 2 towards the visor 7.
- the fresh stream of breathable air is directed at the visor 7 and serves to at least partially demist the visor to improve a wearer’s vision.
- Air that is drawn through the filter 26 into the face mask 2, through the first one way valve 91, and into the oro-nasal mask 3 is inhaled by a wearer. When the wearer exhales, the exhaled air flows back into the oro-nasal mask 3 and creates a positive pressure. This positive pressure opens a second one way valve 92 so that air can flow out of the oro-nasal mask 3.
- the second one-way valve 92 can be seen in Fig. 10.
- the second one-way valve 92 is located in a front wall 93 of the body 4 of the oro-nasal mask 3 distal to its open end 5. As can be seen in Fig.
- the face mask 2 of the breathing apparatus 90 further comprises an exhalation duct 41 configured to channel exhaled air away from the second one way valve 92.
- the present embodiment comprises two ducts 42 which extend downwards from each side of the second one way valve 92.
- the ducts 42 extends in the general direction of a wearer’s chin and have outlets 42 located either side of a wearer’s chin when the breathing apparatus 90 is properly donned.
- the direction of the air flow through the mask can be seen illustrated by arrows in Fig. 13
- the outlet 42 of the exhalation duct 41 is into a closed space between the primary seal, formed by the inner and outer seals 6, 32, and a secondary seal 16, shown in Fig. 14.
- the secondary seal 16 is shown attached to the inner surface of the hood 10. However, it will be understood that in an alternative embodiment, the secondary seal 16 may be attached to the face mask 2.
- a positive pressure builds up in the breathing apparatus. This means that the pressure in the enclosed space 18 is at a higher pressure that the atmosphere so that if any of the seals leak, the only direction of leakage flow is from the high pressure areas close to the wearer’s nose and face towards the hood to compartment outside of the primary and/or secondary seal and towards the atmosphere. In this way, the leakage flow prevents noxious gases or harmful substances reaching the wearer’s respiratory system.
- an outer edge of the secondary seal 16 may be attached to the inner surface of the hood to whilst an inner portion, but not the inner edge of the secondary seal 16 may be attached to a portion of the primary seal, the inner and outer seals 6, 32.
- the exhalation ducts 41 deliver air into an enclosed space 16 between the primary and secondary seals.
- the secondary seal 16 may have a plurality of holes (not shown) to allow the straps of a harness (not shown) to pass through.
- the outlet 42 of the exhalation duct 41 may vent air straight into the hood space 10 and bypass the enclosed space 16.
- the harness 20 maybe split into two sections 51, 52 which are connected by a tensioning mechanism 53 which is schematically shown by a spring.
- the tensioning mechanism 53 maybe, for example, but not limited to, a single or multiple draw string arrangement or a buckle.
- the two sections are a front section 51 which connects to the face mask 2 and a rear section 52 which is placed in contact with the back of the head of a wearer when the breathing apparatus 40 is donned.
- the rear portion 52 may comprises a platform portion 54 which is configured to abut the back of the head of a wearer and may be ergonomically shaped so as to fit against a wearer’s head comfortably.
- the rear section 52 has two opposing ends 55, one positioned on each side of a wearer’s when the breathing apparatus 40 is donned, which are each attached to a tensioning mechanism 53.
- the front section 51 of the harness 20 comprises two branches; an upper branch 56 and a lower branch 57.
- the upper branch 56 has a front end 58 which is attached to the face mask 2 in the region of a wearer’s temple and an opposing rear end 59.
- the front end 58 of the upper branch 56 may be attached in the region of a wearer’s ear or forehead.
- the lower branch 57 has a front end 60 which is attached to the face mask 2 in the region of the oro-nasal mask 3, for example the mouth or chin region, and an opposing rear end 61.
- the rear ends 59, 61 of the upper and lower branches 56, 57 of the front section 51 of the harness 20 are connected to one another and to a front end 63 of the tensioning mechanism 53.
- a balance line shown as a dotted line in Fig. 15, exists between the mounting points of the upper and lower branches 56, 57 on the face mask 2 which is the point at which the forces in the tensioning branches 56, 57 cancel out. Preferably, this is the level at which the platform portion 54 of the rear section 52 is located on the back of a wearer’s head.
- the mounting positions of the front ends 58, 60 of the upper and lower branches 56, 57 can be chosen carefully to align the balance line with the desired position of the rear section 52 on a wearer’s head and to optimise the seal created by the face mask 2 when the tensioning mechanism 53 is tightened to secure the breathing apparatus 40 on a wearer’s head.
- the upper and lower branches 56, 57 of the front section 51 of the harness 20 are flexible such that they can flex, stretch, and/ or twist when the tensioning mechanism 53 is tightened.
- the upper and lower branches 56, 57 of the front section 51 of the harness 20 are formed by rigid elements.
- the upper and lower branched 56, 57 are pivotably mounted at their front ends 58, 60 on the face mask 2 and pivotably connected at their opposing ends 59, 61 to a pivot 64.
- the pivot 63 may be attached by a third rigid member 65 to the front end 63 of the tensioning mechanism 53.
- the pivot 64 maybe directly attached to the front end 62 of the tensioning mechanism 53.
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Abstract
The present invention relates to a breathing apparatus for use in a contaminated environment, the apparatus comprising a face mask comprising an oro-nasal mask configured to surround a wearer's nose and mouth, the oro-nasal mask having an inner seal extending about a periphery of the oro-nasal mask and configured to abut a wearer's face around a wearer's nose and mouth; and a visor connected to the oro-nasal mask; an upper mask portion configured to extend around the visor and surround a wearer's eyes; a hood comprising: a neck opening through which a wearer's head is insertable; and a face opening; wherein the face mask is disposed within the face opening and the face opening of the hood is sealed around the face mask; and the oro- nasal mask further comprising an exhalation duct configured to vent air exhaled by the user into the hood outside of the face mask.
Description
A breathing apparatus
Technical field
The present invention relates to a breathing apparatus. More specifically, the present invention relates to a breathing apparatus for use in a contaminated environment.
Background
Breathing apparatuses are known in the art for use in environments where the ambient atmosphere contains, or may contain, noxious gases or airborne particles that may injure a person if inhaled. Such breathing apparatuses can include full face respirators that have a seal which extends around a wearer’s face and a visor for the wearer to see through. Such respirators seal the wearer’s eyes, nose, and mouth from the atmosphere but leave the periphery of the wearer’s face and the back of the wearer’s head exposed to the contaminated environment.
Therefore, some breathing apparatuses comprise a hood extending from the respirator which only covers a wearer’s nose and mouth, whilst the hood fully encloses the wearer’s head. The hood comprises a neck seal for sealing the wearer’s head from the contaminated environment. The seal(s) formed by breathing apparatuses against a wearer are critical to the performance of the apparatus in a contaminated environment, i.e. the better the seal that is formed against the wearer, the less ingress of harmful particles from the contaminated environment into the breathing apparatus that occurs which results in the fewer harmful particles being inhaled by the wearer. However, known breathing apparatuses suffer from the disadvantage that the seals are not formed sufficiently and so are not effective. As a consequence harmful particles leak through the seals and are inhaled by the wearer. This is a major problem with neck seals on the hood, where the seal must be stretched over the wearer’s head when donning the breathing apparatus. The stretching may damage the seal such that it is no longer effective. In addition, the effectiveness of the neck seal is dependent upon the size of the wearer’s head and neck and whether the wearer is clean shaven or not. Neck seals are known to leak as they often fit poorly around a wearer’s neck, particularly on the rear of the neck.
Summary of the Invention
It is the object of the invention to provide an improved breathing apparatus.
According to the present invention, there is provided a breathing apparatus for use in a contaminated environment, the apparatus comprising a face mask comprising an oro- nasal mask configured to surround a wearer’s nose and mouth, the oro-nasal mask having an inner seal extending about a periphery of the oro-nasal mask and configured to abut a wearer’s face around a wearer’s nose and mouth; and a visor connected to the oro-nasal mask; a hood comprising: a neck opening through which a wearer’s head is insertable; and a face opening; wherein the face mask is disposed within the face opening and the face opening of the hood is sealed around the face mask; and a secondary seal having a central opening, the secondary seal being configured abut the perimeter of a wearer’s face such that a closed space is defined between the face mask and the secondary seal when the breathing apparatus is secured to a wearer’s head.
In one embodiment, the secondary seal may extend from an inner surface of the hood. The secondary seal may comprise at least one hole configured to allow exhaled air to leak from the closed space into the hood. The face mask may further comprise an upper mask portion configured to extend around the visor and surround a wearer’s eyes. Preferably, the upper mask portion comprises an outer seal configured to abut a wearer’s face around the eyes together with the oro-nasal mask. The upper mask portion may be integrally formed with the oro-nasal mask. In one embodiment, the outer seal of the upper mask portion is integrally formed with the inner seal of the oro-nasal mask.
Preferably, the face mask is configured to abut a wearer’s face when a wearer’s face is moved horizontally through the opening in the secondary seal. The inner seal of the oro-nasal mask may comprise a resiliently deformable top portion which is configured to abut a wearer’s nasal ridge before the rest of the inner seal abuts a wearer’s face when the breathing apparatus is donned.
In one embodiment, the breathing apparatus further comprises a harness for securing the face mask to a wearer’s face. The face mask may be securable to a wearer’s face by the tightenable harness.
In one embodiment, the secondary seal may extend from the face mask. Preferably, the secondary seal is configured to abut a wearer’s face when the face mask is moved along a wearer’s face from the forehead towards the chin.
The secondary seal maybe configured to abut around the periphery of a wearer’s face and at least with the underside of a wearer’s chin and a wearer’s forehead. In one embodiment, the secondary seal may be configured such that when the face mask is secured to a wearer’s face the secondary seal abuts a wearer’s face further back on a wearer’s forehead than on the underside of a wearer’s chin.
Preferably, the inner seal of the oro-nasal mask is configured to abut a wearer’s face on a wearer’s chin below the lower lip. The oro-nasal mask may comprise an exhalation duct that is configured to vent air exhaled by a wearer into the hood outside of the face mask. Preferably, the exhalation duct is configured to vent air exhaled by a wearer into the hood outside of the secondary seal. The exhalation duct may be configured to vent air exhaled by a wearer into the hood inside of the secondary seal.
The visor maybe connected proximate to a front portion of the oro-nasal mask at a point distal to a wearer’s face when the breathing apparatus is donned. This means that more of the oro-nasal mask is behind the visor so that there exists a larger area for a breathable air supply means to be connected to the face mask. The larger the area the larger the fluid conduits can be which decreases resistance to a wearer’s inhalation.
In one embodiment, the hood may comprise a handle configured to aid a wearer’s in deploying the hood over their head. The hood may comprise a neck seal configured to abut around the neck of a wearer when the hood is deployed.
The breathing apparatus may further comprise a breathable air supply means fluidly connected with the face mask. In one embodiment, the breathable air supply means may comprise a clean air canister fluidly connected to the respirator. In one embodiment, the breathable air supply means may comprise an air filter.
Preferably, the air filter is fluidly connected to the respirator via a hose. The hose may
comprise two outlets configured to direct breathable air to opposite sides of the visor.
In one embodiment, the hose may have a cross-section configured to remain at least partially open when folded back on itself. In one embodiment, the air filter may be secured to a bib section of the hood which is configured to at least partially cover a wearer’s chest such that the air filter is configured to abut a wearer’s chest.
In accordance with an aspect of the present invention, there is provided a breathing apparatus for use in a contaminated environment, the apparatus comprising a face mask comprising: an oro-nasal mask configured to surround a wearer’s nose and mouth, the oro-nasal mask having an inner seal extending about a periphery of the oro- nasal mask and configured to abut a wearer’s face around a wearer’s nose and mouth; a visor connected to the oro-nasal mask; and an upper mask portion configured to extend around the visor and surround a wearer’s eyes; a hood comprising: a neck opening through which a wearer’s head is insertable; and a face opening; wherein the face mask is disposed within the face opening and the face opening of the hood is sealed around the face mask; and the oro-nasal mask further comprising an exhalation duct configured to vent air exhaled by a user into the hood outside of the face mask.
The breathing apparatus may further comprise a secondary seal having a central opening, the secondary seal being configured to abut the perimeter of a wearer’s face such that a closed space is defined between the face mask and the secondary seal when the breathing apparatus is secured to a wearer’s head.
The secondary seal may comprise at least one hole configured to allow exhaled air to leak from the closed space into the hood. In one embodiment, the secondary seal may extend from an inner surface of the hood. Preferably, the upper mask portion comprises an outer seal configured to abut a wearer’s face around the eyes together with the oro-nasal mask. The upper mask portion may be integrally formed with the oro-nasal mask. In one embodiment, the outer seal of the upper mask portion may be integrally formed with the inner seal of the oro-nasal mask.
Preferably, the face mask maybe configured to abut a wearer’s face when a wearer’s face is moved horizontally through the opening in the secondary seal.
The inner seal of the oro-nasal mask may comprise a resiliently deformable top portion which is configured to abut a wearer’s nasal ridge before the rest of the inner seal abuts a wearer’s face when the breathing apparatus is donned.
In one embodiment, the breathing apparatus may further comprise a harness for securing the face mask to a wearer’s face. The face mask may be securable to a wearer’s face by the adjustable harness.
In one embodiment, the secondary seal may extend from the face mask. Preferably, the secondary seal is configured to abut a wearer’s face when the face mask is moved along a wearer’s face from the forehead towards the chin.
The secondary seal maybe configured to abut around the periphery of a wearer’s face and at least with the underside of a wearer’s chin and a wearer’s forehead.
In one embodiment, the secondary seal may be configured such that when the face mask is secured to a wearer’s face the secondary seal abuts a wearer’s face further back on a wearer’s forehead than on the underside of a wearer’s chin.
Preferably, the inner seal of the oro-nasal mask may be configured to abut a wearer’s face on a wearer’s chin below the lower lip.
The exhalation duct may be configured to vent air exhaled by a wearer into the hood outside of the secondary seal. The exhalation duct maybe configured to vent air exhaled by a wearer into the hood inside of the secondary seal. The visor may be connected proximate to a front portion of the oro-nasal mask at a point distal to a wearer’s face when the breathing apparatus is donned.
In one embodiment, the hood may comprise a gripping means configured to aid a wearer’s in deploying the hood over their head. The hood may comprise a neck seal configured to abut around the neck of a wearer when the hood is deployed.
The breathing apparatus may further comprise a breathable air supply means fluidly connected with the face mask. The breathable air supply means may comprise a clean air canister fluidly connected to the respirator. The breathable air supply means may comprise an air filter.
The air filter may be fluidly connected to the respirator via a hose. The hose may comprise two outlets configured to direct breathable air to opposite sides of the visor. The hose may have a cross-section configured to remain at least partially open when folded back on itself.
The air filter may be secured to a bib section of the hood which is configured to at least partially cover a wearer’s chest such that the air filter is configured to abut a wearer’s chest. The breathable air supply means may be hinged attached to the face mask. These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.
Brief Description of the Drawings
So that the invention may be more fully understood, embodiments thereof will now be described by way of example only, with reference to the accompanying drawings, in which:
Fig. 1 shows a side view of a first embodiment of a breathing apparatus secured to a wearer’s head with a portion of a hood cut away;
Fig. 2 shows a front view of the breathing apparatus of Fig.i with the hood deployed over the wearer’s head;
Fig. 3 shows a side view of a second embodiment of a breathing apparatus secured to a wearer’s head with a portion of a hood cut away;
Fig. 4 shows a front view of the breathing apparatus of Fig. 3 with the hood deployed over the wearer’s head;
Fig. 5 shows a side view of a third embodiment of the breathing apparatus secured to a wearer’s head with a portion of a hood cut away;
Fig. 6 shows a rear view of a breathing apparatus in its stored configuration;
Fig. 7 shows a side view of a fourth embodiment of a breathing apparatus secured to a wearer’s head with a portion of a hood cut away;
Fig. 8 shows a side view of a fifth embodiment of a breathing apparatus secured to a wearer’s head with a portion of a hood cut away;
Fig. 9 shows a front perspective view of a sixth embodiment of a breathing apparatus with a portion of a hood cut away;
Fig. 10 shows a rear perspective view of the breathing apparatus of Fig. 9 with a portion of a hood cut away;
Fig. 11 show a cross-sectional side view of the breathing apparatus of Fig. 9 with a portion of the hood cut away;
Fig. 12 shows a side view of the breathing apparatus of Fig. 9 with a portion of a hood cut away;
Fig. 13 shows a front view of the breathing apparatus of Fig. 9 with a portion of the hood cut away;
Fig. 14 shows a side view of a sixth embodiment of a breathing apparatus secured to a wearer’s head with a portion of the hood cut away;
Fig. isshows a schematic side view of a harness used to secure a breathing apparatus to a wearer’s head; and
Fig. 16 shows a schematic side view of a harness used to secure a breathing apparatus to a wearer’s head- Detailed Description
Referring to Figs. 1 and 2, a breathing apparatus 1 for use in a contaminated
environment is shown. A contaminated environment exists where the ambient atmosphere contains noxious gases or airborne particles that may injure a person if inhaled. In some cases an environment may be considered to be contaminated when there are as little as 2,000 part per million of the noxious gas or harmful particle. Thus, it is important that the breathing apparatus 1 can be put on in the minimum amount of time when a exposure to a noxious gas and/or harmful particle occurs.
The breathing apparatus 1 comprises a face mask 2. The face mask 2 is configured to fit around a wearer’s face when the breathing apparatus 1 is donned. The face mask 2 comprises an oro-nasal mask 3 that is configured to surround a wearer’s nose and mouth. The oro-nasal mask 3 may comprise a hollow body 4, which may be an outer shell 4having an open end 5 which allows a wearer to place their nose and mouth into the oro-nasal mask 3. The outer shell 4 is configured to house components of the breathing apparatus 1, such as, but not limited to, valves (not shown), as will be
discussed in more detail hereinafter. The outer shell 4 may be rigid and formed from, for example, but not limited to,....
The oro-nasal mask 3 further comprises an inner seal 6 which extends about the periphery of the oro-nasal mask 3. The inner seal 6 may extend around the periphery of the hollow body 4 or may extend from within the shell 4 and out of the open end. The inner seal 6 is an inner face mask seal. That is, the inner seal 6 is configured to abut a wearer’s face around a wearer’s nose and mouth. The inner seal 6 is configured to abut a wearer’s face in order to attempt to form a primary seal. Thus, the inner seal 6 of the oro-nasal mask 3 is configured to prevent or at least reduce the amount of noxious gases and/ or harmful particles entering a wearer’s respiratory system when the breathing apparatus 1 is donned in a contaminated environment. In the present embodiment, the inner seal 6 of the oro-nasal mask 3 is configured to abut a wearer’s face on the wearer’s chin below the lower lip and on the wearer’s nasal ridge.
In an alternative embodiment, the oro-nasal mask 3 may not comprise an outer shell 4 and may instead be formed of a single element which surrounds a wearer’s nose and mouth and comprises the inner seal 6 extending about the periphery of its open end 5. Furthermore, a top portion 6a of the inner seal 6 of the oro-nasal mask 3 in the region of the wearer’s nasal ridge may comprise a bellows arrangement. That is, the top of the inner seal 6 which abuts a wearer’s nasal ridge when the breathing apparatus is donned may be resiliently deformable. The resiliently deformable top portion 6a may be configured to abut a wearer’s nasal ridge before the rest of the inner seal 6 abuts a wearer’s face when the breathing apparatus 1 is donned. The top of the inner seal 6 is configured to extend away from the hollow body 4 of the oro-nasal mask 3 before the breathing apparatus 1 is donned. Therefore, during the donning of the breathing apparatus 1, which is described in more detail hereinafter, the time taken for the inner seal 6 of the oro-nasal mask 3 to form a seal around a wearer’s nose and mouth is minimised. Thus, there is a small chance of harmful substances from the contaminated environment entering a wearer’s respiratory system. Because the top of the inner seal 6 is resiliently flexible, like a bellows, the inner seal 6 can be compressed when the breathing apparatus 1 is secured to a wearer’s face. The resilience of the inner seal 6 is small enough such that it cannot bias the oro-nasal mask 3 away from a wearer’s face during use so that the seal 6 formed by the inner seal 6 is not broken after the breathing apparatus has been donned and secured.
The face mask 2 further comprises a visor 7 which is connected to the oro-nasal mask 3. The visor 7 is connected to the body 4 of the oro-nasal mask 3. The visor 7 is sealed to the oro-nasal mask 3 in order to prevent or at least reduce the amount of noxious gases or harmful particles that can pass between the oro-nasal mask 3 and the visor 7. This helps to prevent the noxious gases or harmful particles coming into contact with a wearer’s eyes. The visor 7 maybe curved to partially match the curvature of a wearer’s face or maybe a flat sheet. The visor 7 is formed of a transparent material. That is, the visor 7 maybe formed from, for example, but not limited to,....
In addition, the visor 7 may comprise a position indicating means 8 as shown in Fig. 2. The position indicating means 8 is configured to provide a reference point for a wearer to indicate whether they have donned and positioned the breathing apparatus 1 correctly in order to prevent or at least reduce the amount of noxious gases and/or harmful particles that enter that breathing apparatus 1 and/ or the wearer’s body.
In the present embodiment, as shown in Fig. 2, the position indicating means 8 comprises two circles 9 which indicate where a wearer’s eyes should be positioned in the breathing apparatus 1 when the breathing apparatus 1 is worn properly, as will be discussed in more detail hereinafter. The circles 9 may be formed by a groove in the visor 7 or by a layer of, for example, but not limited to, ink or paint. The circles 9 are formed by a circumferential curve which is hollow. That is, the middle of the circles 9 do not contain any ink or paint so that the wearer’s vision is not obscured. In alternative embodiments, other shapes, such as, for example, but not limited to, crosses or dots may be used.
Preferably the visor 7 is connected proximate to the front portion of the hollow body 4 of the oro-nasal mask 3, as shown in Fig. 5. That is, the visor 7 is mounted on the body 4 of the oro-nasal mask 3 at a point distal to a wearer’s face when the breathing apparatus 1 is donned. Thus, the visor 7 is preferably mounted on the hollow body 4 of the oro-nasal mask 3 in the region of the tip of a wearer’s nose instead of in the region of the nasal ridge of a wearer’s nose. Therefore, there is more space behind the visor 7 for the placement of outlets 24 for the direction of breathable air towards the visor 7, as will be explained in more detail hereinafter.
The breathing apparatus 1 further comprises a hood 10 that is configured to cover a wearer’s head when the breathing apparatus l is worn properly. The hood 10 comprises a neck opening 11 through which a wearer’s head is insertable. Before the breathing apparatus 1 is required it is usually stored in a bag that can be carried by a person in an environment in which contamination of the surroundings is possible. In order to minimise the space used during storage and to aid with donning the breathing apparatus l the hood 10 may be rolled up so that the neck opening n surrounds the face mask 2. In addition, the hood 10 is rolled up such that the secondary seal 16 surrounds the face mask 2 and faces the person about to don the breathing apparatus l. Therefore, a wearer can place their face directly against the face mask 2 through the secondary seal 16 before deploying the hood io. This minimises the amount of time required to don the breathing apparatus l from the realisation that the environment is contaminated and can be vital is protecting a wearer from the harmful environment. An example of an alternative embodiment of the breathing apparatus is shown in Fig. 6 in the storage configuration, as will be described in more detail hereinafter.
A wearer must place their head in the neck opening n and pull the hood io over their head to deploy the hood io so that it fully covers their head. The hood io may further comprise a gripping means 12, shown in Fig. l, such as a handle, toggle, or pull chord, that is configured to aid a wearer in grasping the hood io and pulling it over their head. Advantageously, the grasping means 12 may be placed close to the bottom of the hood 10 next to the neck opening 11 so that a wearer can more easily fully deploy the whole hood 10 over their head. The hood 10 may also further comprise a neck seal 13 extending about the edge of the neck opening 11. The neck seal 13 is configured to abut against a wearer’s neck once the hood 10 has been pulled over a wearer’s head. The neck seal 13 is configured to reduce the amount of noxious gases and/ or harmful particles that enter the hood 10 once the hood 10 has been deployed. In the absence of a neck seal 13, it is preferred that the neck opening 11, or at least a portion of the hood 10 proximate the hood neck opening 11 is elasticated in an attempt to prevent the ingress of harmful substances in the
contaminated environment entering the hood 10.
Furthermore, the hood 10 comprises a face opening 14. The face opening 14 of the hood 10 is configured to receive the face mask 2 of the breathing apparatus 1. That is, the face mask 2 is disposed within the face opening 14. The periphery of the face opening 14 of
the hood 10 is sealed around the face mask 2. Thus, noxious gases and/ or harmful particles are prevented from entering the breathing apparatus 1 through the face opening 14 of the hood 10. In the present embodiment, as shown in Figs. 1 and 2, the face opening 14 is sealed against the oro-nasal mask 3, preferably against the hollow body or outer shell 4, and the visor 7. The face mask 2 may be sealed to the face opening 14 of the hood 10 by adhesive, such as, but not limited to,..., or by other means, such as,....
The breathing apparatus 1 further comprises a secondary seal 16 that comprises a central opening 17. The central opening 17 is configured to allow a wearer to place their face through the secondary seal 16. The secondary seal 16 is configured to abut the perimeter of a wearer’s face. Thus, the secondary seal 16 abuts a wearer’s face closer to a wearer’s ear than the inner seal 6 of the face mask 2. More, specifically, the secondary seal 16 is configured to abut at least with the underside of a wearer’s chin and with a wearer’s forehead. Therefore, the secondary seal may be configured such that when the face mask 2 abuts a wearer’s face, the secondary seal 16 is inclined to the vertical. That is, the portion of the secondary seal 16 which abuts a wearer’s forehead is located further in the horizontal direction from a wearer’s nose than the portion of the secondary seal 16 which abuts a wearer’s chin. In the present embodiment, as shown in Fig. 1, the secondary seal 16 extends from an inner surface of the hood 10.
A closed space 18 is defined between the face mask 2 and the secondary seal 16 when the breathing apparatus 1 is donned by a wearer. The closed space 18 between the inner seal 6 and the secondary seal 16 is configured to form a space which is predominantly filled with breathable air in order to prevent or at least reduce the amount of noxious gases and/or harmful particles that are present within the portion of the hood 10 in which a wearer’s face is located so that the contact between the noxious gases and/or harmful particles and a wearer’s eyes, nose, and mouth, is reduced. The breathing apparatus 1 further comprises a harness 20 for securing the face mask 2 to a wearer’s face. The harness 20 is configured to be placed over a wearer’s head so that the harness 20 extends from the face mask 2 to the back of a wearer’s head. The harness 20 is adjustable. That is, the harness 20 can be tightened once it has been placed over the head of a wearer such that any person, no matter what the size of their head, can use the breathing apparatus 1. The harness 20 is tightened until the face mask 2 is secured to a wearer’s face. The tightening of the harness 20 moves the face
mask 2 of the breathing apparatus l towards a wearer’s face, specifically, a wearer’s nose and mouth, and force the inner seal 6 against the wearer’s face so that a primary seal is formed to prevent noxious gases and/or harmful particles entering a wearer’s respiratory system.
The harness 20 may extend on the inside of the hood to such that the harness 20 must be placed around a wearer’s head and tightened before the hood 10 is pulled down over a wearer’s head. Alternatively, the harness 20 may extend on the outside of the hood 10 such that the hood 10 must be pulled down over a wearer’s head before the harness is placed around a wearer’s head and tightened. In a further alternative embodiment, the harness 20 may be within the material of the hood 10 such that in the same movement as deploying the hood 10 the harness is placed around a wearer’s head. The harness 20 can then be adjusted to the size of a wearer’s head. The harness 20 may be, for example, but not limited to, adjustable straps.
The harness 20 may comprises a strap extending from the mouth portion of the face mask 2. The harness 20 may be designed so that a wearer must pull a strap (not shown) to tighten the harness 20 to secure the breathing apparatus 1 to their face. The harness 20 may be designed so that the at least one strap is either pulled in a direction that a wearer is facing or is pulled behind a wearer’s head.
The breathing apparatus 1 may further comprise a breathable air supply means 22. The breathable air supply means 22 is configured to provide breathable air to a wearer of the breathing apparatus 1 so that a wearer does not breathe in noxious gases and/ or harmful particles that are present in a contaminated environment. The breathable air supply means 22 is fluidly connected to the face mask 2. The breathable air supply means 22 may be fluidly connected to the face mask 2 by, for example, a hose 23. As illustrated in the drawings, the hose 23 may be located outside of the hood 10.
Alternatively, the hose 23 may extend within the hood 10 when the breathing apparatus 1 is donned. In such an embodiment, the hose 23 may pass through the secondary seal
16 which seals around the hose 23 to prevent harmful gases and/or particles entering the face mask portion 2 of the hood 10.
In some embodiments, the hose 23 may be folded back on itself when the breathing apparatus is stored in its bag (not shown) before use. Therefore, the hose 23 has a cross-section that is configured to remain at least partially open when the hose 23 is
folded. For example, the cross-section may comprise a diametrically extending element that extends perpendicularly to the fold line which prevents that cross-section of the tube from closing completely when the hose 23 is folded for storing. This enables a flow of breathable air to the face mask 2 to be provided instantly when the breathing apparatus 1 is removed from the bag because there is no need for a wearer to check that the hose 23 is properly unfolded and that there is no blockage of the flow of breathable air.
The hose 23 is fluidly connected, in the present embodiment, to two outlets 24 that deliver breathable air to the face mask 2, although it will be understood that the number of outlets may vary. The placement of the visor 7 close to the front of the oro- nasal mask 3 allows the hose 23 or ducting to fit into the oro-nasal mask 3 without compromising the cross-sectional area of the hose 23 and in turn raising the resistance to breathing experienced during use.
In one embodiment, the hose 23 may comprise a single duct which branches into two ducts proximate to the face mask 2. The outlets 24 are configured to direct breathable air to opposite sides of the visor 7 through the oro-nasal mask 3. Therefore, the breathable air can be used to“de-mist” the visor 7 to prevent the visor 7 fogging up and obscuring a wearer’s vision. The outlets 24 may direct breathable air towards the position indicating means 8 on the visor 7 or any other portion of the visor 7. In an alternative embodiment, the hose 23 may comprise two ducts which communicate fluidly with one outlet 24 each. In one embodiment, such as the embodiments shown in Fig. 1 and 3, the breathable air supply means 22 comprises an air filter 26. A one-way valve (not shown) may be present such that a wearer of the breathing apparatus may draw air through the filter 26 to be breathed in but cannot breathe air out through the filter 26. However, in an alternative embodiment, the breathable air supply means 22 may comprise a clean air canister (not shown). The flow of breathable air from the clean air canister may be started automatically upon removal of the breathing apparatus 1 from the bag, as is known in the art.
In one embodiment of the breathing apparatus, as shown in Fig. 2, the hood 10 comprises a bib section 28. The bib section 28 is a part of the hood 10 which extends down from the face mask 2 at least partially over a wearer’s chest when the breathing
apparatus 1 is worn properly and the hood 10 is deployed. The breathable air supply means 22, the air filter 26 in the embodiment illustrates, is mounted on the bib portion 28 such that the breathable air supply means 22 abuts a wearer’s chest. Therefore, the weight of the breathable air supply means 22 is supported by a wearer’s chest.
Consequently, the weight of the breathable air supply means 22 acting on the face mask 2 is reduced and the problem of the breathable air supply means 22 pulling the face mask 2, and therefore inner seal 6, away from a wearer’s face is alleviated.
However, other configurations of the breathable air supply means 22 are envisaged, as will be described in more detail hereinafter. For example, in some embodiments, the air filter 26 maybe connected to the face mask 2 via a hinge arrangement 29. The hinge arrangement 29 allows the air filter 26 to be stored in its stowed position within the face mask 2 when the breathing apparatus 1 is stored in its bag (not shown). Therefore, when donning the breathing apparatus 1, the air filter 26 must be rotated about the hinge arrangement to remove the air filter 26 from the face mask 2 to place the air filter 26 in its extended position before a wearer can place their face into the face mask 2.
In some embodiments, such as the configuration shown in Fig. 6, the hinge
arrangement 29 comprises a hinged hose 23 with a coupling 29a. The hose 23 is split into two. One end of a first portion of the hose 23 is connected to the air filter 26 and the other end of the first portion is connected to one half of the coupling. One end of a second portion of the hose is connected to the other half of the coupling and the other end of the second portion is connected to the face mask 2. The coupling is in a hinged open position when the air filter 26 is stowed in the face mask 2 and when the air filter 26 is rotated into its extended position the coupling is hinged closed to form an air tight fluid conduit for breathable air to flow form the air filter 26 into the face mask 2. In an alternative embodiment, the hose 23 may be a flexible tube connecting the air filter 26 and the face mask 2 that can be bent so that the air filter can be stowed in the face mask 2. In such an embodiment, the air filter 26 may be connected to a separate hinge.
In other embodiments, that will be described in more detail hereinafter, the breathable air supply means 22 may be provided on the face mask 2. That is, the breathable air supply means 22 may be mounted on the hollow body or outer shell 4 of the oro-nasal mask 3. In such embodiments, the breathable air supply means 22 maybe a filter.
When a person becomes aware that the environment they are in has become contaminated, they open the bag (not shown) in which the breathing apparatus 1 is stored and remove the breathing apparatus 1 from the bag. As the hood to is rolled up, the neck opening 11 and secondary seal 16 surround the periphery of the face mask 2. The air filter 26 may need to be removed from the face mask 2 by rotating it about the hinge.
A wearer takes the breathing apparatus 1 and moves the breathing apparatus 1 in a direction from a wearer’s forehead towards a wearer’s chin. During this movement, the secondary seal 16 may form an initial, at least partial, seal with a wearer’s face and so may prevent or at least reduce the amount of noxious gases/and or harmful particles that enter the portion of the breathing apparatus 1 in which a wearer places their face. The breathing apparatus 1 is moved down a wearer’s face until the top of the secondary seal 16 abuts a wearer’s forehead and the bottom of the secondary seal 16 locates underneath a wearer’s chin and the oro-nasal mask 3 is positioned roughly over a wearer’s nose and mouth. At this point, the resiliently deformable top portion of the inner seal 6 will abut against the nasal ridge of a wearer’s nose.
A wearer then passes the harness 20 over their head. The harness 20 is then adjusted, usually tightened, until the oro-nasal mask 3 is secured over a wearer’s nose and mouth and the top portion of the inner seal 6 is compressed. During the process of tightening the harness 20, the oro-nasal mask 3 is drawn closer to a wearer’s face so that the inner seal 6 abuts a wearer’s face about their nose and mouth. When the harness 20 is fully tightened, the inner seal 6 seals the nose and mouth from the contaminated
environment. The closed space 18 is defined between the inner seal 6 of the oro-nasal mask 3 and the secondary seal 16.
A wearer then begins to breathe normally. Upon inhalation a negative pressure is caused in the oro-nasal mask 3 and so air is drawn in through a one-way valve (not shown) from the closed space 18. This in turn causes a negative pressure in the closed space 18. A one-way valve (not shown) in the hose 23 is configured such that it opens in response to negative pressure before the secondaiy seal 16. Therefore, breathable air is drawn into the closed space 18 through the air filter 26 rather than contaminated air from outside the secondary seal 16. The breathable air is drawn into the closed space and is directed from the outlets 24 of the hose 23 towards the position indicating means 8 of the visor 7.
Once the breathable air has impinged on the visor 7 to demist the visor 7, it is drawn through the one-way valve (not shown) in the face mask 2 and breathed in by a wearer. When the user exhales, the exhalant cannot exit through the one-way valve (not shown) through which it entered the oro-nasal mask 3 and so exits through a one-way outlet valve (not shown) to the atmosphere.
When the face mask 2 has been properly aligned and secured on a wearer’s face, a wearer may grasp the gripping means 12 and pull the hood 10 down over their head. Once the hood 10 has been fully deployed, the air filter 26 may rest upon a wearer’s chest and the neck seal 13 in the neck opening 11 may abut a wearer’s neck in order to prevent or at least reduce the amount of noxious gases and/or harmful particles entering the hood 10 of the breathing apparatus 1. Referring now to Figs. 3 and 4, there is shown a schematic cross-sectional side view of a second embodiment of the breathing apparatus 30. The breathing apparatus 30 is generally the same as the embodiment of the breathing apparatus 1 described above and so features and components of the breathing apparatus 30 that are the same as the features and components of the breathing apparatus 1 will retain the same terminology and reference numerals. As the breathing apparatus 30 is generally the same as the embodiment of the breathing apparatus 1 described above, a detailed description of similar features and components will be omitted.
The face mask 2 of the breathing apparatus 30 further comprises an upper mask portion 31. The upper mask portion 31 is configured to extend around the visor 7 and surrounds a wearer’s eyes. That is, the upper mask portion 31 is configured to fit around a wearer’s eyes when the breathing apparatus 30 is donned. In the present embodiment, as shown in Figs. 3 and 4, the face opening 14 is sealed against the oro- nasal mask 3, preferably against the hollow body or outer shell 4, and the upper mask portion 31.
The upper mask portion 31 comprises an outer seal 32 which is configured to abut a wearer’s face around the eyes. The outer seal 32 is located within the hood 10. In the present embodiment, the outer seal 32, together with the inner seal 6 of the oro-nasal mask 3, abuts a wearer’s face around the eyes in order to form a primary seal. Thus, the outer seal 32 of the face mask 2 is configured to prevent or at least reduce the amount
of noxious gases and/ or harmful particles entering a wearer’s respiratory system or contacting a wearer’s eyes when the breathing apparatus 30 is donned in contaminated environment. In the present embodiment, the upper mask portion 32 is integrally formed with the oro-nasal mask 3. In addition, the outer seal 32 of the upper mask portion 31 is also integrally formed with the inner seal 6 of the oro-nasal mask 3. Furthermore, in the present embodiment, the secondary seal 16, shown in Fig. 3, extends from the face mask 2 instead of the inner surface of the hood 10. Therefore, in one embodiment, the breathing apparatus may be provided without the hood 10. However, it will be understood that the secondary seal 16 may extends from the inner surface of the hood 10. In the present embodiment, the harness 20 may comprise a strap extending from the mouth portion of the face mask 2 and a strap extending from the temple portion of the face mask 2.
When a person becomes aware that the environment they are in has become contaminated, they open the bag (not shown) storing their breathing apparatus 30 and remove the breathing apparatus 30 from the bag. As the hood 10 is rolled up, the neck opening 11 surrounds the periphery of the face mask 2 and the secondary seal 16 extends out of the neck opening 11 of the hood 10, as illustrated in Fig. 6.
A wearer takes the breathing apparatus 30 and moves the breathing apparatus 30 in a direction from a wearer’s forehead towards a wearer’s chin. During this movement, the secondary seal 16 forms an initial, at least partial, seal with a wearer’s face and prevents or at least reduces the amount of noxious gases/and or harmful particles that enter the portion of the breathing apparatus 30 in which a wearer places their face. The breathing apparatus 30 is moved down a wearer’s face until the top of the secondary seal 16 abuts a wearer’s forehead and the bottom of the secondary seal 16 locates underneath a wearer’s chin and the oro-nasal mask 3 is positioned over a wearer’s nose and mouth so that it forms a seal due to the resiliently deformable top portion of the inner seal 6 abutting against the nasal ridge of a wearer’s nose and the rest of the inner seal contacting the wearer’s face. In the present embodiment, the first effective seal formed is formed by the inner seal 6 of the oro-nasal mask 3 around a wearer’s nose and mouth.
A wearer then passes the harness 20 over their head. The harness 20 is then adjusted, usually tightened, to further secure the oro-nasal mask 3 over a wearer’s nose and mouth. During the process of tightening the harness 20, the oro-nasal mask 3 is drawn closer to a wearer’s face so that the inner seal 6 abuts a wearer’s face with greater force about their nose and mouth. When the harness 20 is fully tightened, the top portion of the inner seal 6 seal is compressed and the nose and mouth is sealed from the contaminated environment. The tightening of the harness 20 also pulls the upper mask portion 31 towards the face such that the outer seal 32 contacts a wearer’s face around the wearer’s eyes. The closed space 18 is defined between the inner seal 6 of the oro- nasal mask 3, the outer seal 32 of the upper mask portion 31 and the secondary seal 16.
A wearer then begins to breathe normally. Upon inhalation a negative pressure is caused in the oro-nasal mask 3 and so air is drawn in through a one-way valve (not shown) from the upper mask portion 31. This in turn causes a negative pressure in the upper mask portion 31. A one-way valve (not shown) in the hose 23 is configured such that it opens in response to negative pressure before the secondary seal 16. Therefore, breathable air is drawn into the upper mask portion 31 through the air filter 26 rather than contaminated air from outside outer seal 32 or the secondary seal 16. The breathable air is drawn into the face mask 2 and is directed from the outlets 24 of the hose 23 towards the position indicating means 8 of the visor 7.
Once the breathable air has impinged on the visor 7 it is drawn through the one-way valve (not shown) in the oro-nasal mask 3 and breathed in by a wearer. When the user exhales, the exhalant cannot exit through the one-way valve (not shown) through which it entered the oro-nasal mask 3 and so exits through a one-way outlet valve (not shown) to the atmosphere. In some embodiments, the outlet valve may be a simple small hole.
When the face mask 2 has been properly aligned and secured on a wearer’s face, a wearer may grasp the gripping means 12 and pull the hood 10 down over their head. Once the hood 10 has been fully deployed, the air filter 26 will rest upon a wearer’s chest and the neck seal 13 in the neck opening 11 may abut a wearer’s neck in order to attempt to prevent noxious gases and/or harmful particles entering the hood 10 of the breathing apparatus 30. Referring now to Fig. 5, there is shown a schematic cross-sectional side view of a third embodiment of a breathing apparatus 40. The breathing apparatus 40 is generally the
same as the embodiment of the breathing apparatus 30 described above and so features and components of the breathing apparatus 40 that are the same as the features and components of the breathing apparatus 30 will retain the same terminology and reference numerals. As the breathing apparatus 40 is generally the same as the embodiment of the breathing apparatus 30 described above, a detailed description of similar features and components will be omitted.
The face mask 2 of the breathing apparatus 40 comprises an oro-nasal mask 3 configured to surround a wearer’s nose and mouth and an upper mask portion 31 which extends around a visor 7 and surrounds a wearer’s eyes. An outer seal 32 of the upper mask portion 31 and an inner seal 6 of the oro-nasal mask 3 abut a wearer’s face around the eyes in order to form a primary seal to at least reduce the amount of noxious gases and/or harmful particles enters a wearer’s respiratory system or contacting a wearer’s eyes when the breathing apparatus 40 is donned in a contaminated environment.
A secondary seal 16 extends from the face mask 2 and has a central opening 17 through which a wearer can place their face to fit the face mask 2 to their face when donning the breathing apparatus 40. Once a wearer’s face is placed into the face mask 2, the primary seal 6, 32 and secondary seal 16 contact a wearer’s face to act as a barrier against the contaminated environment. However, it will be understood that in the present embodiment, the secondary seal 16 may be omitted.
A harness 20 which is connected to the face mask 2 may then be pulled over a wearer’s head and fastened such that the face mask 2 can be worn by a wearer without the wearer having to hold the face mask 2 to their face. Once the harness 20 has been fastened, a hood 10 can be extended from its bundled state in which it is stored and pulled over a wearer’s head. The neck opening 11 of the hood 10 maybe elasticated such that the hood 10 has a narrow portion proximate the neck opening to reduce the flow of air in and out of the hood 10.
When a wearer breathes in, air from a breathable air supply means 22 enters the face mask 2. The breathable air supply means 22 maybe a canister of air or, as shown in Fig. 5, an air filter 26 which hinged on the face mask 2 and fluidly connected to the face mask 2 by a hose 23. In the present embodiment, the air filter 26 is mounted on the bib section 28 of the hood 10. However, in alternative embodiments, the air filter 26 may be mounted on the oro-nasal mask 3 in front of a wearer’s mouth or two air filters 26
maybe mounted on the side of the oro-nasal mask 3; one over each cheek of the wearer.
Air is drawn through the filter 26 and is filtered so that breathable air is directed from outlets 24 towards the position indicating means 8 of the visor 7. Once the breathable air has impinged on the visor 7 and demisted the visor 7 so that a wearer can see out of the face mask 2 whilst wearing the breathing apparatus 40, it is drawn through a one- way valve (not shown) in the oro-nasal mask 3 and breathed in by a wearer. The one- way valve (not shown) in the filter 26 prevents moisture in the exhaled air flowing back into the filter26 and clogging the filter 26.
In the present embodiment, the oro-nasal mask 3 further comprises an exhalation duct 41 which is configured to vent air that is exhaled by a wearer out of the oro-nasal mask 3. The exhalation duct 41 has an outlet 42 which is located in the hood 10 of the breathing apparatus 40 such that the air exhaled by a wearer is directed into the space within the hood 10 outside of the seals formed against a wearer’s face but inside the neck opening 11 of the hood 10. In the present embodiment, the outlet 42 of the exhalation duct 41 is located outside of the secondary seal 16. However, in an embodiment in which the secondary seal 16 is omitted, the outlet 42 of the exhalation duct 41 is located outside the primary seal formed by the inner seal 6 and the outer seal 32.
By way of example, as illustrated in the embodiment shown in Fig. 5, an exhalation duct 41 extends horizontally from the side of the oro-nasal mask 3 around a wearer’s face to its outlet 42 behind the secondary seal 16. The duct 41 comprises a one-way valve (not shown) so that exhaled air, or any harmful gases trapped in the hood 10, cannot be breathed in through the duct 41 by the wearer.
Due to the weight of the carbon dioxide gas in the air exhaled by the wearer, the carbon dioxide will sink towards the neck opening 11 the bottom of the hood 10 once it has exited the outlet 42 of the exhalation duct 41. Therefore, the carbon dioxide gas is not breathed back in by the user. Furthermore, by diverting the flow of exhaled air into the hood 10 instead of directly to the atmosphere, a barrier of non-harmful air can be built up between the secondary seal 16 and the neck opening 11 of the hood 10. Therefore, if the primary seal 6, 32 or secondary seal 16 are not in contact with a wearer’s face all the way around their periphery because, for example, the wearer wears glasses or has a
beard, the harmful gases from the contaminated environment can be prevented from entering the closed space 18 in the face mask 2 because any leakage from the hood 10 outside the secondary seal 16 will be air exhaled by the wearer which will have extremely low concentrations, if any, of harmful substances from the contaminated atmosphere.
Referring now to Fig. 7, there is shown a schematic cross-sectional side view of a fourth embodiment of a breathing apparatus 70. The breathing apparatus 70 is generally the same as the embodiment of the breathing apparatus 40 described above and so features and components of the breathing apparatus 70 that are the same as features and components of the breathing apparatus 40 will retain the same terminology and reference numerals. As the breathing apparatus 70 is generally the same as the embodiment of the breathing apparatus 40 described above, a detailed description of similar features and components will be omitted.
In the present embodiment, the exhalation duct 41, which extends from the oro-nasal mask 3, has its outlet 42 in the space 18 between the primary seal 6, 32 of the face mask 2 and the secondary seal 16. Therefore, when a wearer exhales, the exhaled air exits outside of the primary seal 6, 32 but inside of the secondary seal 16.
As more air is exhaled into the space 18, pressure builds up in the space 18. The relative high pressure that forms in the space 18 maybe restrictive on a wearer’s breathing. Therefore, in order to relieve the pressure build up, the secondary seal 16 may be configured to move out of contact with a wearer’s face. The secondary seal 16 may move out of contact with a wearer’s face due to being configured to form a weaker seal with a wearer’s face than the primary seal 6, 32. Due to the relative high pressure in the space 18 compared to the relative low pressure outside of the secondary seal 16 but within the hood 10, the free movement of air between the space 18 and the hood 10 is restricted. In fact, the pressure differential between the exhaled air in the space 18 and the air in the hood 10 outside the secondary seal 16 results in air flow from the space 18 into the hood 10. Therefore, harmful gases are prevented from entering the face mask 3.
In some embodiments, such as the one shown in Fig. 7, the secondary seal 16 may be configured to that it remains sealed to a wearer’s face as the pressure in the space 18 increases. This may be achieved by configuring the secondary seal 18 such that it forms a stronger seal with a wearer’s face. In such an embodiment, the pressure may become
sufficiently high such that it becomes difficult for a wearer to breathe out into the space. Therefore, in order to alleviate the pressure build up without the secondary seal moving out of contact with a wearer’s face, the secondary seal 18 is provided with a hole 71 configured to allow exhaled air to leak from the space 18 between the primary seal 6, 32 and the secondary seal 16 into the space in the hood 10.
It will be appreciated that in some embodiments, the secondary seal 16 may comprise a plurality of holes 71. The holes 71 may be evenly spaced around the secondary seal 16 or located in groups. It will be understood from the description above that in the embodiment illustrated in Fig. 7 does not require a hole 71 in the secondaiy seal 16 to function and that any number of holes 71 in the secondary seal 16 is optional. In the absence of a hole 71, positive air pressure in the enclosed space 18 may leak out of the enclosed space between the secondary seal 16 and a wearer’s face, as will be described in more detail hereinafter.
The holes 71 are sized to prevent the free flow of air between the two spaces but allow air under high pressure in the space 18 to leak into the hood 10. In this way, harmful gases and/ or substances from the contaminated environment can be prevented from entering the face mask 2. In some embodiments, the holes 71 may comprise one-way valves configured to only allow air flow from the space 18 into the hood 10 and prevent air flow form the hood 10 into the space 18.
Preferably, the exhaled air that is breathed out into the space 18 will pass the secondary seal 16 by moving the secondary seal 16 out of contact with a wearer’s face. However, when the pressure in the space is large enough to restrict a wearer’s breathing or provide significant resistance against a wearer’s exhaling into the space 18, the exhaled air in the space 18 may leak through the holes 71 in the secondary seal 16 from the space 18 into the hood 10. Referring now to Fig. 8, there is shown a schematic cross-sectional view of a fifth embodiment of a breathing apparatus 80. The breathing apparatus is generally the same as the embodiment of the breathing apparatus 40 described above and so features and components of the breathing apparatus 80 that are the same as features and components of the breathing apparatus 40 will retain the same terminology and reference numerals. As the breathing apparatus 80 is generally the same as the
embodiment of the breathing apparatus 40 described above, a detailed description of similar features and components will be omitted.
However, in the present embodiment, the outer seal 32 that extends about the upper mask portion 31 of the face mask 2 is omitted. The face mask 3 is bonded to the hood 10 and the secondary seal 16 provides a barrier between the space 18 in the face mask 3 and the space in the hood 10.
Referring now to Figs. 9 to 14, there is shown a perspective view of a sixth embodiment of a breathing apparatus 90. The breathing apparatus 90 is generally the same as the embodiments of the breathing apparatuses described above and so features and components of the breathing apparatus 90 will retain the same terminology and reference numerals. As the breathing apparatus 90 is generally the same as the embodiment of the breathing apparatuses described above, a detailed description of similar features and components will be omitted.
The breathing apparatus 90 is for use in a contaminated environment where the atmosphere contains noxious gases or airborne particles that may injure a person if inhaled. As shown in Figs. 9 and 10, the breathing apparatus 90 comprises a face mask 2. The face mask 2 is configured to fit around a wearer’s face when the breathing apparatus 90 is donned. The face mask 2 comprises an oro-nasal mask 3 that is configured to surround a wearer’s nose and mouth. The oro-nasal mask 3 comprises an hollow body 4 having an open end 5 which allows a wearer to place their nose and mouth into the oro-nasal mask 3. The hollow body 4 is connected to the breathable air supply means 22 which in this case is an air filter 26 mounted on the face mask 2. As shown in Fig. 11 the filter 26 closes an installation hole 96 in the front of the oro-nasal mask 3 which is used for installing a valve which will be described in more detail below.
The oro-nasal mask 3 comprises a hollow body 4 having an open end 5 which allows a wearer to place their nose and mouth into the oro-nasal mask 3. The oro-nasal mask 3 further comprises an inner seal 6 which extends about the periphery of the oro-nasal mask 3. The inner seal 6 forms part of the primary inner face mask seal. That is, the inner seal 6 is configured to abut a wearer’s face around a wearer’s mouth and nose. Thus, the inner seal 6 of the oro-nasal mask 3 is configured to prevent or at least reduce the amount of noxious gases and/ or harmful particles entering a wearer’s respiratory system when the breathing apparatus 1 is donned in a contaminated environment. In
the present embodiment, the inner seal 6 of the oro-nasal mask 3 is configured to abut a wearer’s face on the wearer’s chin below the lower lip and on the wearer’s nasal ridge.
The face mask 2 of the breathing apparatus 90 further comprises an upper mask portion 31 that is configured to extend around a visor 7, which is connected to the oro- nasal mask 3, and is configured to fit around a wearer’s eyes when the breathing apparatus 90 is donned. The upper mask portion 31 of the face mask 2 is integrally formed with the oro-nasal mask 3. The visor 7 is sealed against the oro-nasal mask 3 on its lower side and against the upper mask portion 31 on its remaining sides to prevent noxious gases passing into the face mask 2.
The upper mask portion 31 of the face mask 2 comprises an outer seal 32 which is configured to abut a wearer’s face around the eyes. The outer seal 32 is integrally formed with the inner seal 6 of the oro-nasal mask 3 such that together they form a primary seal around a wearer’s face which when donned forms two specific sealed volumes, one around a wearer’s nose and mouth and one around a wearer’s eyes. The outer seal 32 of the face mask 2 is configured to prevent or at least reduce the amount of noxious gases and/ or harmful particles entering a wearer’s respiratory system or contacting a wearer’s eyes when the breathing apparatus 30 is donned in contaminated environment.
The breathing apparatus 90 further comprises a hood 10 that is configured to cover a wearer’s head when the breathing apparatus 90 is fully donned. The hood 10 is shown partially removed in Figs. 9 and 10. Fig. 9 shows where a face opening 14 of the hood 10, which receives the face mask 2, is sealed against the face mask 2 and in this case the filter 26. The hood 10 maybe thermally sealed or sealed by adhesive to the face mask 2 and filter 26. Thus, noxious gases and/or harmful particles are prevented from entering the breathing apparatus 1 through the face opening 14 of the hood 10. The hood 10 may comprise a neck opening, gripping means, and/or neck seal (not shown).
When the breathing apparatus 90 is removed from its storage container it will be in a configuration similar to the one shown in Fig. 6, except for the fact that the breathing apparatus 90 will comprise a filter 26 mounted on the front of the face mask 2 instead of on the bib such that the hose of Fig. 6 will not be present and the filter 26 will not be stored in the area where a wearer’s head will eventually be placed.
When the face mask 2 of the breathing apparatus 90 is placed on a wearer’s face during the donning process, the inner and outer seals 6, 32 abut a wearer’s face around the eyes, nose, and mouth to create a primary seal. When the primary seal has been created, inhalation by a wearer causes a negative pressure within the oro-nasal mask 3. As the inner seal 6 prevents or at least reduces leakage into or out of the oro-nasal mask 3, air must be drawn into the oro-nasal mask 3 through the filter 26 via a first one-way valve 91 located in the body 4 of the oro-nasal mask 3. In Fig. 9, one first one way valve 91 can be seen on a side face of the body 4 of the oro-nasal mask 3. There may be another first one way valve 91 on the other side of the oro-nasal mask 3.
As air is drawn into the oro-nasal mask 3 through the first one way valve(s) 91, a low pressure is created in the upper mask section 31 of the face mask 2. This low pressure draws air through the filter 26 and into the face mask 2 towards the visor 7. The fresh stream of breathable air is directed at the visor 7 and serves to at least partially demist the visor to improve a wearer’s vision.
Air that is drawn through the filter 26 into the face mask 2, through the first one way valve 91, and into the oro-nasal mask 3 is inhaled by a wearer. When the wearer exhales, the exhaled air flows back into the oro-nasal mask 3 and creates a positive pressure. This positive pressure opens a second one way valve 92 so that air can flow out of the oro-nasal mask 3. The second one-way valve 92 can be seen in Fig. 10. In the present embodiment, the second one-way valve 92 is located in a front wall 93 of the body 4 of the oro-nasal mask 3 distal to its open end 5. As can be seen in Fig. 12, the face mask 2 of the breathing apparatus 90 further comprises an exhalation duct 41 configured to channel exhaled air away from the second one way valve 92. The present embodiment comprises two ducts 42 which extend downwards from each side of the second one way valve 92. The ducts 42 extends in the general direction of a wearer’s chin and have outlets 42 located either side of a wearer’s chin when the breathing apparatus 90 is properly donned. The direction of the air flow through the mask can be seen illustrated by arrows in Fig. 13 In such an embodiment, the outlet 42 of the exhalation duct 41 is into a closed space between the primary seal, formed by the inner and outer seals 6, 32, and a secondary seal 16, shown in Fig. 14. In Fig. 14, the secondary seal 16 is shown attached to the inner surface of the hood 10. However, it will be understood that in an alternative embodiment, the secondary seal 16 may be attached to the face mask 2.
When air is exhaled and vented into the hood to, i.e. within the hood of the breathing apparatus in contrast to out into the hazardous environment, a positive pressure builds up in the breathing apparatus. This means that the pressure in the enclosed space 18 is at a higher pressure that the atmosphere so that if any of the seals leak, the only direction of leakage flow is from the high pressure areas close to the wearer’s nose and face towards the hood to compartment outside of the primary and/or secondary seal and towards the atmosphere. In this way, the leakage flow prevents noxious gases or harmful substances reaching the wearer’s respiratory system.
In one embodiment, an outer edge of the secondary seal 16 may be attached to the inner surface of the hood to whilst an inner portion, but not the inner edge of the secondary seal 16 may be attached to a portion of the primary seal, the inner and outer seals 6, 32. In such an arrangement, the exhalation ducts 41 deliver air into an enclosed space 16 between the primary and secondary seals. The secondary seal 16 may have a plurality of holes (not shown) to allow the straps of a harness (not shown) to pass through. In an embodiment in which the secondary seal 16 extends from the face mask 2, the outlet 42 of the exhalation duct 41 may vent air straight into the hood space 10 and bypass the enclosed space 16.
In one embodiment, as shown in Fig. 15, the harness 20 maybe split into two sections 51, 52 which are connected by a tensioning mechanism 53 which is schematically shown by a spring. The tensioning mechanism 53 maybe, for example, but not limited to, a single or multiple draw string arrangement or a buckle. The two sections are a front section 51 which connects to the face mask 2 and a rear section 52 which is placed in contact with the back of the head of a wearer when the breathing apparatus 40 is donned. The rear portion 52 may comprises a platform portion 54 which is configured to abut the back of the head of a wearer and may be ergonomically shaped so as to fit against a wearer’s head comfortably. The rear section 52 has two opposing ends 55, one positioned on each side of a wearer’s when the breathing apparatus 40 is donned, which are each attached to a tensioning mechanism 53.
The front section 51 of the harness 20 comprises two branches; an upper branch 56 and a lower branch 57. The upper branch 56 has a front end 58 which is attached to the face mask 2 in the region of a wearer’s temple and an opposing rear end 59. Alternatively, the front end 58 of the upper branch 56 may be attached in the region of a wearer’s ear
or forehead. The lower branch 57 has a front end 60 which is attached to the face mask 2 in the region of the oro-nasal mask 3, for example the mouth or chin region, and an opposing rear end 61. The rear ends 59, 61 of the upper and lower branches 56, 57 of the front section 51 of the harness 20 are connected to one another and to a front end 63 of the tensioning mechanism 53. Alternatively, there may be a further portion (not shown) connecting the rear ends 59, 61 of the upper and lower branches 56, 57 of the front section 51 of the harness 20 to the tensioning mechanism 53.
A balance line, shown as a dotted line in Fig. 15, exists between the mounting points of the upper and lower branches 56, 57 on the face mask 2 which is the point at which the forces in the tensioning branches 56, 57 cancel out. Preferably, this is the level at which the platform portion 54 of the rear section 52 is located on the back of a wearer’s head. The mounting positions of the front ends 58, 60 of the upper and lower branches 56, 57 can be chosen carefully to align the balance line with the desired position of the rear section 52 on a wearer’s head and to optimise the seal created by the face mask 2 when the tensioning mechanism 53 is tightened to secure the breathing apparatus 40 on a wearer’s head.
In the embodiment shown in Fig. 15, the upper and lower branches 56, 57 of the front section 51 of the harness 20 are flexible such that they can flex, stretch, and/ or twist when the tensioning mechanism 53 is tightened.
However, in an alternative embodiment, as shown in Fig. 16, the upper and lower branches 56, 57 of the front section 51 of the harness 20 are formed by rigid elements. In such an embodiment, the upper and lower branched 56, 57 are pivotably mounted at their front ends 58, 60 on the face mask 2 and pivotably connected at their opposing ends 59, 61 to a pivot 64. The pivot 63 may be attached by a third rigid member 65 to the front end 63 of the tensioning mechanism 53. Alternatively, the pivot 64 maybe directly attached to the front end 62 of the tensioning mechanism 53.
Although the two embodiments of the harness 20 are illustrated in conjunction with the third embodiment of the breathing apparatus 40, it will be understood that such embodiments of the harness 20 can be used together with the other embodiment of the breathing apparatus.
Claims
1. A breathing apparatus for use in a contaminated environment, the apparatus comprising:
a face mask comprising:
an oro-nasal mask configured to surround a wearer’s nose and mouth, the oro-nasal mask having an inner seal extending about a periphery of the oro-nasal mask and configured to abut a wearer’s face around a wearer’s nose and mouth;
a visor connected to the oro-nasal mask; and
an upper mask portion configured to extend around the visor and surround a wearer’s eyes;
a hood comprising:
a neck opening through which a wearer’s head is insertable; and a face opening;
wherein the face mask is disposed within the face opening and the face opening of the hood is sealed around the face mask; and
the oro-nasal mask further comprising an exhalation duct configured to vent air exhaled by a user into the hood outside of the face mask.
2. The breathing apparatus according to claim l, further comprising a secondary seal having a central opening, the secondary seal being configured to abut the perimeter of a wearer’s face such that a closed space is defined between the face mask and the secondary seal when the breathing apparatus is secured to a wearer’s head.
3. The breathing apparatus according to claim l or claim 2, wherein the secondary seal comprises at least one hole configured to allow exhaled air to leak from the closed space into the hood.
4. The breathing apparatus according to any one of the preceding claims, wherein the secondary seal extends from an inner surface of the hood.
5. The breathing apparatus according to any one of the preceding claims, wherein the upper mask portion comprises an outer seal configured to abut a wearer’s face around the eyes together with the oro-nasal mask.
6. The breathing apparatus according to claim 5, wherein the upper mask portion is integrally formed with the oro-nasal mask.
7. The breathing apparatus according to claim 5 or claim 6, wherein the outer seal of the upper mask portion is integrally formed with the inner seal of the oro-nasal mask.
8. The breathing apparatus according to any one of the preceding claims, wherein the face mask is configured to abut a wearer’s face when a wearer’s face is moved horizontally through the opening in the secondary seal.
9. The breathing apparatus according to any one of the preceding claims, wherein the inner seal of the oro-nasal mask comprises a resiliently deformable top portion which is configured to abut a wearer’s nasal ridge before the rest of the inner seal abuts a wearer’s face when the breathing apparatus is donned.
10. The breathing apparatus according to any one of the preceding claims, further comprising a harness for securing the face mask to a wearer’s face.
11. The breathing apparatus according to claim 10, wherein the face mask is securable to a wearer’s face by the adjustable harness.
12. The breathing apparatus according to any one of claim 2 to claim 11, wherein the secondary seal extends from the face mask.
13. The breathing apparatus according to any one of claim 2 to claim 12, wherein the secondary seal is configured to abut a wearer’s face when the face mask is moved along a wearer’s face from the forehead towards the chin.
14. The breathing apparatus according to any one of claim 2 to claim 13, wherein the secondary seal is configured to abut around the periphery of a wearer’s face and at least with the underside of a wearer’s chin and a wearer’s forehead.
15. The breathing apparatus according to claim 14, wherein the secondary seal is configured such that when the face mask is secured to a wearer’s face the secondary
seal abuts a wearer’s face further back on a wearer’s forehead than on the underside of a wearer’s chin.
16. The breathing apparatus according to any one of the preceding claims, wherein the inner seal of the oro-nasal mask is configured to abut a wearer’s face on a wearer’s chin below the lower lip.
17. The breathing apparatus according to any one of claim 2 to claim 16, wherein the exhalation duct is configured to vent air exhaled by a wearer into the hood outside of the secondary seal.
18. The breathing apparatus according to any one of claim 2 to claim 16, wherein the exhalation duct is configured to vent air exhaled by a wearer into the hood inside of the secondary seal.
19. The breathing apparatus according to any one of the preceding claims, wherein the visor is connected proximate to a front portion of the oro-nasal mask at a point distal to a wearer’s face when the breathing apparatus is donned.
20. The breathing apparatus according to any one of the preceding claims, wherein the hood comprises a gripping means configured to aid a wearer’s in deploying the hood over their head.
21. The breathing apparatus according to any one of the preceding claims, wherein the hood comprises a neck seal configured to abut around the neck of a wearer when the hood is deployed.
22. The breathing apparatus according to any one of the preceding claims, further comprising a breathable air supply means fluidly connected with the face mask.
23. The breathing apparatus according to claim 22, wherein the breathable air supply means comprises a clean air canister fluidly connected to the respirator.
24. The breathing apparatus according to claim 22, wherein the breathable air supply means comprises an air filter.
25. The breathing apparatus according to claim 24, wherein the air filter is fluidly connected to the respirator via a hose.
26. The breathing apparatus according to claim 25, wherein the hose comprises two outlets configured to direct breathable air to opposite sides of the visor.
27. The breathing apparatus according to claim 25 or claim 26, wherein the hose has a cross-section configured to remain at least partially open when folded back on itself.
28. The breathing apparatus according to any one of claim 24 to claim 27, wherein the air filter is secured to a bib section of the hood which is configured to at least partially cover a wearer’s chest such that the air filter is configured to abut a wearer’s chest.
29. The breathing apparatus according to any one of claim 22 to claim 28, wherein the breathable air supply means is hinged attached to the face mask.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
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GB1806680.3A GB2575233A (en) | 2018-04-24 | 2018-04-24 | A breathing apparatus |
GB1806680.3 | 2018-04-24 |
Publications (1)
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WO2019207304A1 true WO2019207304A1 (en) | 2019-10-31 |
Family
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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PCT/GB2019/051148 WO2019207304A1 (en) | 2018-04-24 | 2019-04-24 | A breathing apparatus |
Country Status (2)
Country | Link |
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GB (1) | GB2575233A (en) |
WO (1) | WO2019207304A1 (en) |
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CN111905225A (en) * | 2020-08-26 | 2020-11-10 | 四川省肿瘤医院 | Protective isolation cover |
CN113040445A (en) * | 2021-03-25 | 2021-06-29 | 日照三奇医疗卫生用品有限公司 | Protective clothing |
IL281493A (en) * | 2021-03-14 | 2022-10-01 | Testa Tech T T Ltd | Wearable gear |
USD1026203S1 (en) | 2021-01-28 | 2024-05-07 | E.D. Bullard Company | Powered air-purifying respirator carriage assembly |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
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US20220118290A1 (en) * | 2020-10-21 | 2022-04-21 | DRS Innovations LLC | Powered air filtration face covering |
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EP0470791A2 (en) * | 1990-08-10 | 1992-02-12 | Sabre Safety Limited | Emergency escape breathing apparatus |
US7028688B1 (en) * | 2005-04-05 | 2006-04-18 | The United States Of America As Represented By The Secretary Of The Army | Operationally adaptable chemical-biological mask |
WO2014029511A2 (en) * | 2012-08-24 | 2014-02-27 | Msa Auer Gmbh | Protective hood |
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GB2367755B (en) * | 2000-08-01 | 2002-08-28 | Joseph Anthony Griffiths | Emergency escape hood |
US6895960B2 (en) * | 2001-01-18 | 2005-05-24 | 3M Innovative Properties Company | Modular respirators and a method of conversion thereof |
GB201014618D0 (en) * | 2010-09-03 | 2010-10-13 | Qinetiq Ltd | Respirtory protection equipment |
WO2013044009A1 (en) * | 2011-09-23 | 2013-03-28 | Lion Apparel, Inc. | Molded facepiece gasket |
US20140190476A1 (en) * | 2012-02-07 | 2014-07-10 | Diving Unlimited International, Inc. | Seal for full face mask |
JP6234844B2 (en) * | 2014-03-06 | 2017-11-22 | 興研株式会社 | Sealing device for protective mask |
US10926114B2 (en) * | 2016-04-15 | 2021-02-23 | Scott Technologies, Inc. | Removable battery cartridge for facemask |
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2018
- 2018-04-24 GB GB1806680.3A patent/GB2575233A/en not_active Withdrawn
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2019
- 2019-04-24 WO PCT/GB2019/051148 patent/WO2019207304A1/en active Application Filing
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EP0470791A2 (en) * | 1990-08-10 | 1992-02-12 | Sabre Safety Limited | Emergency escape breathing apparatus |
US7028688B1 (en) * | 2005-04-05 | 2006-04-18 | The United States Of America As Represented By The Secretary Of The Army | Operationally adaptable chemical-biological mask |
WO2014029511A2 (en) * | 2012-08-24 | 2014-02-27 | Msa Auer Gmbh | Protective hood |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111905225A (en) * | 2020-08-26 | 2020-11-10 | 四川省肿瘤医院 | Protective isolation cover |
USD1026203S1 (en) | 2021-01-28 | 2024-05-07 | E.D. Bullard Company | Powered air-purifying respirator carriage assembly |
IL281493A (en) * | 2021-03-14 | 2022-10-01 | Testa Tech T T Ltd | Wearable gear |
IL281493B1 (en) * | 2021-03-14 | 2023-08-01 | Testa Tech T T Ltd | Wearable gear |
IL281493B2 (en) * | 2021-03-14 | 2023-12-01 | Testa Tech T T Ltd | Wearable gear |
CN113040445A (en) * | 2021-03-25 | 2021-06-29 | 日照三奇医疗卫生用品有限公司 | Protective clothing |
Also Published As
Publication number | Publication date |
---|---|
GB2575233A (en) | 2020-01-08 |
GB201806680D0 (en) | 2018-06-06 |
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