CONTAINER FOR PACKAGED FILTRATION MASK
20220135307 · 2022-05-05
Inventors
Cpc classification
A62B27/00
HUMAN NECESSITIES
B65D79/005
PERFORMING OPERATIONS; TRANSPORTING
B65D75/5805
PERFORMING OPERATIONS; TRANSPORTING
A62B18/08
HUMAN NECESSITIES
B65D2201/00
PERFORMING OPERATIONS; TRANSPORTING
A62B25/00
HUMAN NECESSITIES
A62B23/025
HUMAN NECESSITIES
B65D79/008
PERFORMING OPERATIONS; TRANSPORTING
International classification
B65D79/00
PERFORMING OPERATIONS; TRANSPORTING
A62B18/08
HUMAN NECESSITIES
B65D75/58
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A packaged filtration mask can include a filtration mask packaged in a container in a vacuum or a partial vacuum. The container can be a tearable container, at least a portion of which can include a laminate of a first part and a second part. A resistance to tearing of the second part can be different than a resistance to tearing of the first part.
Claims
1. A tearable container, wherein: at least a portion of the tearable container comprises a laminate of a first part and a second part; a resistance to tearing of the second part is greater than a resistance to tearing of the first part; and the second part includes a channel portion for directing a tear along the laminate.
2. The tearable container according to claim 1, wherein the second part is omitted, or has a reduced resistance to tearing, in the channel portion.
3. The tearable container according to claim 1, wherein there is a filtration mask packaged in the tearable container.
4. The tearable container according to claim 1, wherein the first part is a laminate of a plurality of layers.
5. The tearable container according to claim 1, wherein the second part is a single layer.
6. The tearable container according to claim 1, wherein the channel portion extends along a curved line.
7. The tearable container according to claim 1, wherein the channel portion curves around a corner of the tearable container.
8. The tearable container according to claim 1, wherein the channel portion extends from a first position proximal to a top side of the container to a second position proximal to a bottom side of the tearable container.
9. The tearable container according to claim 1, wherein the channel portion extends along, or adjacent to, a side of the tearable container.
10. The tearable container according to claim 1, wherein the first part comprises a laminate of: a first layer of oriented polyamide; a second layer of aluminium foil; a third layer of oriented polyamide; and a fourth layer of linear low-density polyethylene.
11. The tearable container according to claim 1, wherein the second part comprises a layer of high-density polyethylene.
12. The tearable container according to claim 1, wherein: there is a filtration mask packaged in the tearable container; and the position and length of the channel portion are configured such that tearing the tearable container along the channel portion opens the tearable container such that the filtration mask can be removed from the container.
13. A blank for making a tearable container according to claim 1.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0202] Embodiments of the present invention will now be discussed, by way of example only, with reference to the accompanying Figures, in which:
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS AND FURTHER OPTIONAL FEATURES OF THE INVENTION
[0215] Embodiments of the present invention will now be discussed with reference to
[0216]
[0217] As shown in
[0218] The filtration mask 1 comprises an oro-nasal mask 3 that fits over the wearer's nose and mouth.
[0219] Two filters 5 are connected to the oro-nasal mask 3.
[0220] An exhale unit 7 is positioned centrally on a front surface of the filtration mask 1 between the two filters 5. The exhale unit 7 includes an indicator for indicating the presence of, or lack of, a vacuum or a partial vacuum in a container in which the filtration mask is packaged, which is discussed in detail below.
[0221] The filtration mask 1 further comprises a hood portion 9 which is configured to extend over the wearer's head.
[0222] At the bottom of the hood portion 9 there is an elastomeric neck dam 11 which includes an opening through which the wearer puts his head. The hood portion 9 and neck dam 11 are typically connected at a join or seam, created by e.g. a weld.
[0223] The filters 5 are in fluid communication with the oro-nasal mask 3, so that when wearer of the mask inhales, the reduction in pressure inside the oro-nasal mask 3 causes ambient gas to be sucked into the oro-nasal mask 3 through the filters 5.
[0224] The filters 5 include a filtration medium, such as activated carbon, which can filter one or more substances from the inhaled ambient gas, so as to provide filtered gas that does not include the one or more substances (or that includes reduced amounts of the one or more substances) for breathing by the wearer of the mask.
[0225] The structure of the filters 5 is discussed in more detail below.
[0226] The structure of the exhale unit 7 is shown in more detail in
[0227] The exhale unit 7 allows gas exhaled into the filtration mask 1 to be discharged to outside the filtration mask 1, but prevents ambient gas from being inhaled into the filtration mask 1 through the exhale unit 7.
[0228] Specifically, the exhale unit 7 includes a valve 13 that allows flow of gas in a direction from the inside of the filtration mask 1 to the outside of the filtration mask 1 (upwards in
[0229] The exhale unit 7 further comprises an exhale module body 15 and an exhale module cover 17, which together enclose the valve 13.
[0230] The exhale module body 15 is connected to, or is integral with, a main body of the filtration mask 1, and/or the filters 5.
[0231] Furthermore, the exhale unit 7 includes a tactile dome component 19, which forms the indicator of an embodiment of the present invention. The tactile dome component 19 is positioned on top of the exhale module cover 17.
[0232] Finally, the exhale unit 7 may include an optional sticker 21 positioned on top of the tactile dome component 19.
[0233] The tactile dome component 19 in this embodiment is a stainless steel component, which in a specific example may be a stainless steel tactile dome component manufactured by Snaptron Inc.
[0234] In a rest state (“a second configuration”), the tactile dome component 19 substantially has a dome shape.
[0235] When a force greater than a predetermined threshold is applied to the tactile dome component 19 from above (from the top in
[0236] Once the threshold force is exceeded, the shape of the tactile dome component 19 rapidly changes from the dome shape to the compressed/depressed dome shape, providing tactile feedback to a person applying the force to the tactile dome component 19.
[0237] Furthermore, the tactile dome component 19 makes an audible sound, specifically a click sound, when changing from the dome shape to the compressed dome shape, or when changing from the compressed dome shape to the dome shape, providing audible feedback to a person applying the force to the tactile dome component 19.
[0238] The tactile dome component 19 is resilient, such that when the force applied to the tactile dome component 19 is removed, the tactile dome component 19 rapidly changes from the compressed/depressed dome shape to the dome shape.
[0239] As shown in
[0240] The tactile dome component 19 is positioned on top of the exhale unit 7, and is therefore easily accessible on the front face of the filtration mask 1.
[0241] Furthermore, the tactile dome component 19 protrudes from the front face of the filtration mask 1.
[0242] For storage before use, the filtration mask 1 is vacuum sealed in a vacuum bag (a container), to protect the filtration mask 1 from contamination and/or degradation caused by ambient gas.
[0243] Specifically, the filtration mask 1 is packaged inside a vacuum bag with the hood portion etc. folded beneath the filters 5 and the exhale unit 7. The filters 5 and exhale unit 7 therefore form an upper surface of the filtration mask 1 packaged in the vacuum bag.
[0244] When a vacuum or partial vacuum is formed inside the vacuum bag, the vacuum bag is collapsed around the filtration mask 1 and applies pressure to the filtration mask 1.
[0245] Since the tactile dome component 19 is positioned on top of the exhale unit 7 on the upper surface of the filtration mask 1 packaged in the vacuum bag, the tactile dome component 19 is adjacent to an inner surface of the vacuum bag. Therefore, when the vacuum bag is collapsed around the filtration mask 1, the inner surface of the vacuum bag applies pressure to the tactile dome component 19. This pressure is sufficient to compress/depress the tactile dome component 19 into the compressed/depressed dome shape (“the first configuration”), and to hold the tactile dome component 19 in this configuration. If a person inspecting the packaged filtration mask subsequently applies a further force to the tactile dome component 19 through the vacuum bag, there will be substantially no response, because the tactile dome component 19 is already compressed/depressed by the vacuum or partial vacuum in the vacuum bag, and therefore the person will not experience any tactile or audible feedback.
[0246] As such, a person inspecting the packaged filtration mask is able to determine that there is a vacuum or a partial vacuum inside the vacuum bag by pressing on the tactile dome component 19 through the vacuum bag and not experiencing any tactile or audible feedback. The tactile dome component therefore acts to indicate a state of (presence of, or lack of) a vacuum or partial vacuum inside the vacuum bag.
[0247] The fact that the exhale unit 7 and therefore the tactile dome component 19 are in the centre of the filter units 5 means that a person inspecting the packaged filtration mask can press on the tactile dome component 19 by pressing on a centre of a main surface of the vacuum bag, which is convenient.
[0248] If the vacuum bag is breached for any reason, such that ambient gas enters the vacuum bag, the vacuum or partial vacuum inside the vacuum bag will be lost as ambient gas enters the vacuum bag. Since there will then no longer be a significant pressure difference between the gas in the vacuum bag and the ambient gas, the vacuum bag will no longer provide any significant force on the tactile dome component 19. The resilience of the tactile dome component 19 means that it will then automatically return to the dome shape (“the second configuration”) from the compressed/depressed dome shape (“the first configuration”).
[0249] As shown in
[0250] The left hand image in
[0251] The filtration mask 1 is packaged in the vacuum bag 23 with the front face of the filtration mask 1, comprising the exhale unit 7 and the two filters 5, on a top surface of the filtration mask, beneath the main surface of the vacuum bag 23 illustrated in
[0252] Specifically, the right hand image in
[0253] When there is no vacuum or partial vacuum inside the vacuum bag, the tactile dome component 19 has the uncompressed dome shape. If a person inspecting the packaged filtration mask applies a force to the tactile dome component 19 through the vacuum bag that is greater than the threshold force required to compress/depress the tactile dome component 19, the tactile dome component 19 will then be compressed/depressed to the compressed/depressed shape. The person pressing on the tactile dome component 19 will therefore experience a tactile feedback indicating that the tactile dome component was in the dome shape when they pressed on it. Furthermore, they will also experience an audible feedback, due to the click noise made then the tactile dome component 19 is compressed/depressed.
[0254] When the person then removes the force on the tactile dome component 19, the tactile dome component 19 will then return to the uncompressed dome shape, accompanied by a further audible feedback.
[0255] The person applies the force to the tactile dome component 19 by applying pressure to the vacuum bag in an area over the tactile dome component 19.
[0256] As such, a person inspecting the packaged filtration mask is able to determine that there is no vacuum or partial vacuum inside the vacuum bag by pressing on the tactile dome component 19 through the vacuum bag and experiencing a tactile or audible feedback.
[0257] Therefore, the person inspecting the packaged filtration mask is able to accurately determine the state of (presence of, or lack of) the vacuum or partial vacuum inside the vacuum bag merely by pressing on part of (typically the centre of a main face of) the vacuum bag.
[0258] As shown in
[0259] As shown in
[0260] The protective case 27 is flexible/deformable, such that a person inspecting the packaged filtration mask can apply pressure to the marking or indication 29 of the protective case 27 so as to apply pressure to the tactile dome component 19 through the vacuum bag. The person can experience any resulting tactile or audible feedback through the protective case 27.
[0261] Therefore, the person inspecting the packaged filtration mask can inspect the state of (presence of, or lack of) the vacuum inside the vacuum bag without needing to remove the vacuum bag from the protective case 27, which will prolong the life of the packaged filtration mask through reduced wear and tear on the vacuum bag that would otherwise be caused by the need to regularly remove the vacuum bag from the protective case 27 for inspection.
[0262]
[0263] As shown in
[0264] Specifically, a person opening the vacuum bag 23 can do so by pulling the handles 31 in opposite directions (into and out of the page in
[0265] In a conventional vacuum bag, tearing open the vacuum bag, particularly in a hurry in an emergency, can result in unpredictable tearing of the vacuum bag. For example, it is possible for just a corner of the vacuum bag to tear off, leaving the user struggling to open the vacuum bag sufficiently to remove the filtration mask from the vacuum bag.
[0266] In an embodiment of the present invention, an additional tear resistant layer that includes a channel to guide a tear of the vacuum bag 23 is included in the vacuum bag 23.
[0267] As shown in
[0268] Thus, a first main surface of the vacuum bag 23 comprises a laminate of the first part 33 and the second part 35. A second main surface of the vacuum bag 23 opposite to the first main surface comprises the first part 33.
[0269] The second part 35 has a greater resistance to tearing than the first part 33. In other words, it is more difficult for a person to tear the second part 35 than it is for the person to tear the first part 33. The second part 35 can therefore be considered to be a reinforcing layer that reinforces the first part 33 against tearing.
[0270] When the filtration mask 1 is packaged in the vacuum bag 23, the filtration mask 1 is located in the vacuum bag 23 with the front face of the filtration mask 1 comprising the filters 5 and the exhale module 7 adjacent to the second main surface of the vacuum bag 23.
[0271] As shown in
[0272] The channel 37 is elongate, and is sandwiched between regions of the second part 35 on the first part 33.
[0273] Since the tear resistant second part 35 is omitted in the channel 37, the vacuum bag 23 is much easier to tear along the channel 37 than through the laminate of the first part 33 and the second part 35. When a tear is started immediately beneath the handles, the tear therefore preferentially propagates along the channel 37, such that the channel 37 directs or guides the tear along the vacuum bag 23. The channel 37 starts immediately below the handles 31 so that the tear preferentially starts in the channel 37.
[0274] As such, the direction and extent of the tear of the vacuum bag 23 can be precisely controlled.
[0275] When the tear reaches the end point 39 of the channel 37, the resistance to tearing significantly increases due to the presence of the second part 35. Thus, an end point for the tear can clearly be felt by a person opening the vacuum bag 23, and further tearing of the vacuum bag 23 can be prevented.
[0276] As shown in
[0277] The provision of the second part 35 and the channel 37 therefore allows precise control of the tearing of the vacuum bag 23 by a user, even when the user is in a hurry in an emergency situation. Reliable quick opening of the vacuum bag 23 by the user can therefore be ensured.
[0278] The position of the end point 39 of the channel 37 can be selected to prevent the filtration mask 1 from falling out of the vacuum bag 23 during opening, whilst providing sufficient access for the user to easily remove the filtration mask 1 from the vacuum bag 23. This can be achieved by carefully selecting a distance of the end point 39 from a bottom of the vacuum bag 23. In addition, or alternatively, the position of the start point of the channel 37 can be selected to prevent the filtration mask 1 from falling out of the vacuum bag 23 during opening, whilst providing sufficient access for the user to easily remove the filtration mask 1 from the vacuum bag 23. This can be achieved by positioning the start point of the channel 37 part way between the two sides of the vacuum bag 23, as shown in
[0279] In a specific example, the first part 33 may be a laminate of the following materials: 15 micron oriented Polyamide/8 micron aluminium foil/15 micron oriented Polyamide/130 micron linear low density polyethylene.
[0280] The second part 35 may be made of high density polyethylene.
[0281] As shown in
[0282] The filters 5 include a filtration media for filtering ambient gas to produce filtered gas. For example, the filtration media may be activated carbon.
[0283] The filters 5 further include a filtration media support for supporting the filtration media. For example, the filtration media support may be an enclosure for enclosing the filtration media.
[0284] The filtration media support comprises a filter cover that covers the filtration media and compresses the filtration media. In particular, the filter cover needs to provide a necessary amount of compression force on the filtration media to maintain the filtration media in the correct position at the correct density.
[0285] In a conventional filtration mask, the filter cover has a flat, planar surface facing the filtration media for applying the compression force on the filtration media.
[0286] The present inventors have realised that in such an arrangement the resultant force acting on the filter cover due to the compression of the filtration media is perpendicular to the plane of the filter cover. This can result in bending and distortion of the filter cover, unless the filter cover is made from a significantly strong material such as metal, or has a significant thickness.
[0287] In an embodiment of the present invention, the filter cover instead has a non-planar surface facing the filter media.
[0288] Examples of a filter cover 41 according to an embodiment of the present invention are illustrated in
[0289] As shown in
[0290] In particular, the non-planar surface 43 comprises a plurality of different undulations/waves/vaults, such that the non-planar surface has an undulating/wavy/vaulted surface profile. This means that a height of the surface perpendicular to a plane of the filter cover varies over the surface of the filter cover.
[0291] The undulations/waves/vaults occur periodically with a fixed period over the surface.
[0292] As shown in
[0293] As shown in
[0294] The undulating/wavy/vaulted surface of the filter cover 41 in embodiments of the present invention means that a direction of a normal force on the filter cover 41 from the compression of the filter media varies across the surface, because the direction of the surface normal varies across the surface due to the undulations/waves/vaults.
[0295] This means that the normal forces acting on the filter cover 41 are spread out and distributed over the filter cover 41, rather than merely acting directly perpendicular to the filter cover 41 as would be the case with a filter cover with a flat surface. This means that bending or deformation of the filter cover 41 can be reduced in embodiments of the present invention while still applying the necessary compression force on the filtration media.
[0296] This means that the filter cover 41 can be made of a weaker material such as plastic, for example injection moulded plastic, instead of metal. Such a material may be lighter and cheaper.
[0297] This also means that a thickness of the filter cover 41 can be reduced, for example to 2 mm or less, again reducing the cost and/or weight of material.
[0298] As shown in
[0299] Although individual embodiments have been discussed above, all, or any combination of, the above described embodiments can be combined in further embodiments of the present invention.
[0300] Numerous modifications to the above embodiments will be apparent to the skilled person without departing from the scope of the appended claims.
[0301] For example, in the first embodiment an indicator other than the tactile dome component can be used. For example, the indicator may have a different shape to a dome shape, and/or may move between two different positions instead of being compressed/depressed, and/or may be located in a different part of the filtration mask or container.
[0302] For example, in the second embodiment, the channel of the second part may have a different configuration. For example, the channel may comprise a portion where the thickness of the second part is reduced rather than omitting the second part, or where the resistance to tearing of the second part is otherwise reduced, for example by providing perforations in the second part. The tearable container may also or alternatively have a different configuration to the vacuum bag illustrated in
[0303] In the third embodiment, other shapes and/or configurations of non-planar surface can be used instead of the specific example of the non-planar surface illustrated in
[0304] Other aspects and/or embodiments of the present invention may be as specified in the following numbered clauses:
[0305] 1. A packaged filtration mask comprising a filtration mask packaged in a container in a vacuum or a partial vacuum, wherein the packaged filtration mask comprises an indicator configured to indicate the presence of a vacuum or a partial vacuum in the container, or configured to indicate the lack of a vacuum or a partial vacuum in the container.
[0306] 2. The packaged filtration mask according to clause 1, wherein the indicator is configured to adopt a first configuration when there is a vacuum or a partial vacuum in the container, and to adopt a second configuration when there is not a vacuum or a partial vacuum in the container.
[0307] 3. The packaged filtration mask according to clause 2, wherein changing between the first configuration and the second configuration comprises deformation or movement of the indicator.
[0308] 4. The packaged filtration mask according to clause 2 or clause 3, wherein:
[0309] changing from the second configuration to the first configuration comprises compression of the indicator; and
[0310] changing from the first configuration to the second configuration comprises expansion of the indicator.
[0311] 5. The packaged filtration mask according to any one of clauses 2 to 4, wherein the indicator is changeable from the second configuration to the first configuration by the application of a force to the indicator.
[0312] 6. The packaged filtration mask according to clause 5, wherein the container is a flexible container, and wherein when there is a vacuum or a partial vacuum in the flexible container, the flexible container is configured to apply a force to the indicator to change the indicator from the second configuration to the first configuration.
[0313] 7. The packaged filtration mask according to clause 5 or clause 6, wherein the indicator is configured to change back from the first configuration to the second configuration when the force is not applied to the indicator.
[0314] 8. The packaged filtration mask according to any one of clauses 5 to 7, wherein a force greater than a predetermined threshold needs to be applied to the indicator to change the indicator from the second configuration to the first configuration.
[0315] 9. The packaged filtration mask according to any one of clauses 5 to 8, wherein the indicator is changeable from the second configuration to the first configuration when there is not a vacuum or a partial vacuum in the container by applying a force to the indicator through the container.
[0316] 10. The packaged filtration mask according to any one of clauses 5 to 9, wherein:
[0317] the packaged filtration mask comprises a second container in which the container is contained; and
[0318] the indicator is changeable from the second configuration to the first configuration when there is not a vacuum or a partial vacuum in the container by applying a force to the indicator through the second container and the first container.
[0319] 11. The packaged filtration mask according to any one of clauses 2 to 10, wherein the indicator makes a noise when changing from the second configuration to the first configuration.
[0320] 12. The packaged filtration mask according to any one of the previous clauses, wherein: [0321] the indicator comprises a dome switch that is resiliently compressible from a domeshape to a compressed dome shape by application of a force to the dome switch.
[0322] 13. The packaged filtration mask according to clause 12, wherein:
[0323] the dome switch is configured to adopt the dome shape when there is not a vacuum or a partial vacuum in the container; and
[0324] the dome switch is configured to adopt the compressed dome shape when there is a vacuum or a partial vacuum in the container.
[0325] 14. The packaged filtration mask according to any one of the previous clauses, wherein the indicator is part of the filtration mask.
[0326] 15. The packaged filtration mask according to any one of the previous clauses, wherein the indicator is positioned on an outer surface of the filtration mask.
[0327] 16. The packaged filtration mask according to any one of the previous clauses, wherein the indicator is positioned on top of an exhale module of the filtration mask.
[0328] 17. The packaged filtration mask according to any one of the previous clauses, wherein the indicator is on a front face of the filtration mask in the centre of a filter portion of the filtration mask.
[0329] 18. The packaged filtration mask according to any one of the previous clauses, wherein part of a surface of the container is in contact with the indicator and moves or deforms when the indicator changes between the first state and the second state.
[0330] 19. The packaged filtration mask according to clause 18, wherein the part of the surface of the container in contact with the indicator is discernible, marked or indicated on the container.
[0331] 20. The packaged filtration mask according to any one of the previous clauses, wherein the container is a tearable container, and wherein:
[0332] at least a portion of the tearable container comprises a laminate of a first part and a second part;
[0333] a resistance to tearing of the second part is greater than a resistance to tearing of the first part; and
[0334] the second part includes a channel portion for directing a tear along the laminate.
[0335] 21. A filtration mask comprising an indicator that is configured to adopt a first configuration when the filtration mask is packaged in a container and there is a vacuum or a partial vacuum in the container, and to adopt a second configuration when the filtration mask is packaged in a container and there is not a vacuum or a partial vacuum in the container.
[0336] 22. A tearable container, wherein:
[0337] at least a portion of the tearable container comprises a laminate of a first part and a second part;
[0338] a resistance to tearing of the second part is greater than a resistance to tearing of the first part; and
[0339] the second part includes a channel portion for directing a tear along the laminate.
[0340] 23. The tearable container according to clause 22, wherein the second part is omitted, or has a reduced resistance to tearing, in the channel portion.
[0341] 24. The tearable container according to clause 22 or clause 23, wherein there is a filtration mask packaged in the tearable container.
[0342] 25. The tearable container according to any one of clauses 22 to 24, wherein the first part is a laminate of a plurality of layers.
[0343] 26. The tearable container according to any one of clauses 22 to 25, wherein the second part is a single layer.
[0344] 27. The tearable container according to any one of clauses 22 to 26, wherein the channel portion extends along a curved line.
[0345] 28. The tearable container according to any one of clauses 22 to 27, wherein the channel portion curves around a corner of the tearable container.
[0346] 29. The tearable container according to any one of clauses 22 to 28, wherein the channel portion extends from a first position proximal to a top side of the container to a second position proximal to a bottom side of the tearable container.
[0347] 30. The tearable container according to any one of clauses 22 to 29, wherein the channel portion extends along, or adjacent to, a side of the tearable container.
[0348] 31. The tearable container according to any one of clauses 22 to 30, wherein the first part comprises a laminate of:
[0349] a first layer of oriented polyamide;
[0350] a second layer of aluminium foil;
[0351] a third layer of oriented polyamide; and
[0352] a fourth layer of linear low-density polyethylene.
[0353] 32. The tearable container according to any one of clauses 22 to 31, wherein the second part comprises a layer of high-density polyethylene.
[0354] 33. The tearable container according to any one of clauses 22 to 32, wherein:
[0355] there is a filtration mask packaged in the tearable container; and
[0356] the position and length of the channel portion are configured such that tearing the tearable container along the channel portion opens the tearable container such that the filtration mask can be removed from the container.
[0357] 34. A blank for making a tearable container according to any one of clauses 22 to 33.
[0358] 35. The packaged filtration mask according to any one of clauses 1 to 20 or the filtration mask according to clause 21, wherein the filtration mask comprises a filter, wherein the filter comprises:
[0359] a filtration media for filtering ambient gas to produce filtered gas; and
[0360] a filtration media support for supporting the filtration media, wherein the filtration media support comprises a filter cover that covers the filtration media and compresses the filtration media;
[0361] wherein a main surface of the filter cover facing the filtration media is a non-planar surface.
[0362] 36. A filtration mask comprising a filter, wherein the filter comprises:
[0363] a filtration media for filtering ambient gas to produce filtered gas; and
[0364] a filtration media support for supporting the filtration media, wherein the filtration media support comprises a filter cover that covers the filtration media and compresses the filtration media;
[0365] wherein a main surface of the filter cover facing the filtration media is a non-planar surface.
[0366] 37. The filtration mask according to clause 36, wherein the main surface of the filter cover is:
[0367] an undulating surface; or
[0368] a vaulted surface; or
[0369] a wavy surface; or
[0370] a multi-faceted surface.
[0371] 38. The filtration mask according to clause 37, wherein the undulation or vaulting or waves of the main surface of the filter cover have a fixed period.
[0372] 39. The filtration mask according to any one of clauses 36 to 38, wherein the filter cover comprises holes arranged in a tessellation pattern.
[0373] 40. The filtration mask according to any one of clauses 36 to 39, wherein the filter cover comprises holes arranged in a hexagonal honeycomb pattern.
[0374] 41. The filtration mask according to any one of clauses 36 to 40, wherein the filter cover is made from plastic.
[0375] 42. The filtration mask according to any one of clauses 36 to 41, wherein the filter cover has a thickness of 2 mm or less.