WO2015035101A2

WO2015035101A2 - Facemask with filter insert for protection against airborne pathogens

Info

Publication number: WO2015035101A2
Application number: PCT/US2014/054163
Authority: WO
Inventors: Steve WATERFORD
Original assignee: Waterford Mask Systems Inc.
Priority date: 2013-09-04
Filing date: 2014-09-04
Publication date: 2015-03-12
Also published as: WO2015035101A3

Abstract

A facemask includes one or more airflow intakes in a lower front section of the mask. The airflow intake is capable of directing inward airflow to strike an interior air filter at an oblique angle. The air filter can be replaceable and/or biocidal. In another embodiment, the facemask includes one or more air vents for bidirectional flow of air being inhaled and exhaled by the wearer, a head mounting pad having a single pull to tension the facemask against the wearer's face, a continuous strap positionable under the chin of the wearer, and a nose bridge clip positionable by the wearer before and during the tensioning of the strap. The facemask can also include a transparent eye shield.

Description

Attorney Docket No. 11087 WOO 1

FACEMASK WITH FILTER INSERT FOR PROTECTION AGAINST AIRBORNE PATHOGENS

Cross-Reference to Related Application(s)

[0001] This application is related to and claims priority benefits U.S. Provisional Patent Application Serial No. 61/873,400 filed on September 4, 2013, entitled "Facemask With Filter Insert For

Protection Against Airborne Pathogens". The '400 provisional application is hereby incorporated by reference herein in its entirety.

Field of the Invention

[0002] The present invention relates to facemasks and, in particular, to a facemask that includes a filter insert designed to protect the wearer, the patient and others in the vicinity of the wearer, from airborne pathogens. The mask can also include a protective eye shield and sound-resonating diaphragms.

Background of the Invention

[0003] In the medical field, surgical masks are often used as a form of protection against airborne pathogens, including bacteria and viruses. Facemasks are typically worn over the mouth and nose of the wearer, and can incorporate a form of eye protection. These masks can also provide similar benefits in non-medical environments. For example, they can be used in environments with high levels of large airborne particulates or allergens, or where the wearer wishes to avoid physical contact between environmental pathogens and their mouth and nose.

[0004] Since the early 1900's, surgical masks have been in widespread use to help prevent infection of surgical wounds from staff-generated nasal and oral bacteria. According to the National Institute for Occupational Safety and Health (NIOSH), three clinical studies conducted in the 1980's and 90s found no difference in surgical infection rates when staff did not wear surgical masks.

NIOSH also published that to be effective in reducing a wearer's exposure to airborne substances, a respiratory protection device needs to have sufficient fit as well as high filtration efficiency. NIOSH also stated that a recent laboratory study of five surgical masks with "good" filters found that 80-100% of subjects failed an OSHA- accepted qualitative fit test. (See CDC - NIOSH Science Blog - N95 Respirators and Surgical Masks at http://blogs.cdc.gov/niosh-science- blog/2009/10/n95/).

[0005] Removing airborne pathogens and environmental allergens is not only very important in environments that require high levels of air purity, such as hospitals, but also in homes of people suffering from allergic responses to allergens. Additionally, wearers suffering from respiratory infections would benefit from the removal of pathogens and allergens when out in public.

[0006] Conventional designs focus on protecting patients from potentially harmful exhalations from the medical professional. Such designs trap vapor and liquid droplets in exhalations that contain potential airborne pathogens, thereby preventing them from contacting the patient and others in the vicinity of the wearer. These masks also provide limited protection for the medical professional by forming a physical barrier over the wearer's mouth and nose, preventing the accidental touching of these areas or the inhalation of airborne particles or droplets.

[0007] Previous designs can attach to the wearer's head by means of tie straps or headbands. These designs can also attach through non- adjustable holes cut into the mask designed to fit around the wearer's ear. Alternatively, they can also fasten using elastic straps around the head or ears. Rectangular cross-sectional elastics are often used, which can cause discomfort by stretching or pinching the skin around the ears and back of the head.

[0008] Conventional mask designs generally do not include a biocide-coated insert. They rely instead on droplet-trapping fabrics and physical barriers for protection. Those that do incorporate such inserts often require the wearer to rupture an envelope through physical force to become operable. This rupturing requirement can introduce problems such as the wearer forgetting to rupture the envelope, the wearer being unable to rupture the envelope or an accidental premature rupturing, rendering the biocidal substance ineffective.

[0009] In conventional designs, wearer's exhalations are generally directed out through the mask in front of the wearer. Airborne pathogens not entrapped by the mask are effectively sent directly towards the patient. Additionally, these masks often provide a poor seal between the mask and the face due to the force of exhalations and non-adjustable elastic fittings that do not fit snuggly around the wearer's head facial area.

[0010] Respirators with a NIOSH rating of N95-100 are more commonly used in environments where greater protection is required than that provided by surgical masks. Yet, these designs suffer from the inherent flaws:

[0011] (1) ties or elastic strap connections that connect along the sides of the mask near parallel to the upper nose seal area and thus, when sufficiently tied or tensioned to seal against the face, simultaneously pull the mask away from the upper nose seal area, preventing a complete seal; [0012] (2) wearers have the option of improperly fitting the mask to their face and/or insufficiently pinching inward the conformable strip in a generic nose bridge area; and

[0013] (3) little or no upward lift is provided by either ties or elastic straps for a proper seal in the chin area.

[0014] Accordingly, a mask that secures snuggly and comfortably to the wearer's face with an adjustable and comfortable elastic design, and that includes a replaceable biocidal insert, would more effectively protect both the wearer, the patient and others in the vicinity of the wearer.

[0015] The present improved facemask designs overcome

shortcomings and disadvantages of prior designs by incorporating a continuous strap that is integrated with the nose bridge to generate a tri-directional force directed downwardly and approximately

perpendicularly to the nose at the nose bridge area. The continuous strap, or nose bridge clip with strap, is placed at the nose bridge location in a manner that is customized to the wearer's face and not in a generic, non-adjustable position. The continuous strap construction pulls the mask upward below the chin while simultaneously pulling the mask backward into the face. Summary of the Invention

[0016] Shortcomings of conventional facemasks are overcome by a facemask comprising at least one airflow intake in a lower front section thereof. The at least one airflow intake capable of directing inward airflow to strike an interior air filter at an oblique angle.

[0017] The air filter can be replaceable and/or biocidal.

[0018] In an embodiment, the facemask has no directly front-facing openings. The facemask preferably further comprises air channeling features that direct exhalations downward and backward towards the wearer's neck. The facemask preferably further comprises a continuous strap structure with a semi-rigid lower section extending towards the wearer's ears and a plurality of spaced extrusions with a gap between each extrusion. The lower strap section preferably extends behind the wearer's ears and a flexible section curves in a semi-circular manner at a common distance.

[0019] The facemask preferably further comprises an elastic section that extends forward therefrom to complete the continuous strap in front of the wearer's face.

[0020] The facemask preferably further comprises a nose clip section within a forward-most center section of the continuous strap section and a pair of downwardly-facing lobe extrusions. [0021] The facemask preferably further comprises a pair of through-holes formed within a flexible center structure. The through- holes are preferably spaced equidistantly between the pair of lobe extrusions. The facemask preferably further comprises a pair of hollowed extrusions along the topmost interior rim on either side of the curved topmost section. A pair of flexible circular openings is preferably formed on either side of the wearer's mouth, each of which has interior channels suitable for mounting at least one resonating diaphragm.

[0022] The facemask can further comprising a transparent eye shield comprising a pair of extrusions insertable into the pair of through-holes such that the eye shield is secured to the wearer's nose area and inclined inward to rest the top portion against the wearer's forehead.

[0023] In another embodiment, a facemask comprises:

[0024] (a) at least one air vent for bidirectional flow of air being inhaled and exhaled by the wearer, the at least one airflow intake capable of directing inward airflow to strike an interior air filter at an oblique angle;

[0025] (b) a head mounting pad having a single pull to tension the facemask against the wearer's face; [0026] (c) a continuous strap positionable under the chin of the wearer;

[0027] (d) a nose bridge clip positionable by the wearer before and during the tensioning of the strap.

[0028] In the foregoing embodiment, the air filter is preferably replaceable and/or biocidal. The at least one vent is preferably a plurality of vents. The vent is preferably configured to direct exhaled air downwardly and backwardly towards the neck of the wearer. The nose bridge clip is preferably configurable to provide a compression zone over the wearer's nose. The compression zone preferably comprises portions of differing flexibility. The head mounting pad has an opening formed in an interior portion thereof, such that, for example, a wearer with hair in a ponytail can extend the ponytail through the opening and in a direction away from the wearer's head.

Brief Description of the Drawings

[0029] FIG. 1 is a perspective view taken from the back side of an embodiment of a facemask assembly with biocidal insert for protection against airborne pathogens.

[0030] FIG. 2 is a perspective view taken from the front side of the facemask assembly illustrated in FIG. 1. [0031] FIG. 3 is a front view of the facemask illustrated in FIGS. 1 and 2.

[0032] FIG. 4 is a back view of the facemask illustrated in FIGS. 1- 3.

[0033] FIG. 5 is a side view of the facemask illustrated in FIGS. 1-4 with the strap unsecured.

[0034] FIG. 6 is a side cutaway view of the facemask illustrated in FIGS. 1-5 with the filter inserted;

[0035] FIG. 7 is a bottom view of the facemask illustrated in FIGS. 1-6.

[0036] FIG. 8 is a perspective view of a filter insert for use in the facemask illustrated in FIGS. 1-7.

[0037] FIG. 9 is a side cross-sectional view of the filter insert illustrated in FIG. 8.

[0038] FIG. 10 is a perspective view of the front side of the facemask illustrated in FIGS. 1-6 with an eye shield attached.

[0039] FIG. 11 is a perspective view of the front side of the facemask illustrated in FIGS. 1-6 with a pair of side resonators.

[0040] FIG. 12 is a perspective view taken from the back side of another embodiment of a facemask assembly. [0041] FIG. 13 is a perspective view taken from the front side of the facemask assembly illustrated in FIG. 12.

[0042] FIG. 14A is a side view of the facemask assembly illustrated in FIGS. 12 and 13.

[0043] FIG. 14B is a side view of the facemask assembly illustrated in FIGS. 12 and 13 with alternative cross-strapping indicated by dashed lines.

[0044] FIG. 15 A is a detailed perspective view of the nose bridge clip of the facemask illustrated in FIGS. 12-14.

[0045] FIG. 15B is a perspective view of a section of the facemask illustrated in FIGS. 12-14 showing detail of the nose bridge clip.

[0046] FIG. 16 is a detailed perspective view taken from the underside of the facemask illustrated in FIGS. 12-15.

[0047] FIG. 17 is a back view of the facemask illustrated in FIGS. 12-16.

[0048] FIG. 18 is a detailed perspective view of the nose clip, continuous strap and head mount pad of the facemask assembly illustrated in FIGS. 12 and 13 taken from the back side of the facemask assembly. Detailed Description of Preferred Embodiment(s)

[0049] As used herein "elastic" is intended to mean the state or quality of being elastic, flexible, resilient and/or adaptable.

[0050] As used herein "oblique" is intended to mean the state of being neither perpendicular nor parallel to a given line or surface; slanting; sloping.

[0051] As used herein "additive manufacturing" is intended to mean a process of making a three-dimensional solid object of virtually any shape from a digital model.

[0052] As used herein "diaphragm" is intended to mean a thin disk that vibrates when receiving or producing sound waves, as in a telephone, microphone, speaker or the like.

[0053] When describing elements of FIGS. 1-11, the same number is used to identify elements that are the same or substantially similar to each other in the different views illustrated in FIGS. 1-11.

[0054] Turning first to FIGS. 1 and 2, illustrating a facemask assembly 1 A, an elastic facemask 1 has a plurality of air channels 2 and side vents 3 formed therein for directing exhaled air flowing from the wearer's mouth down and back towards the neck of the wearer, and for directing inhaled air flowing into facemask 1 so as to strike a filter insert (not shown in FIGS. 1 and 2). at an oblique angle to enhance the capture and retention of airborne pathogens and

particulates.

[0055] As shown in FIGS. 1 and 2, a continuous strap 4 has a pair of lobes configured to press down against the wearer's nasal bone area. Strap 4 has a more elastic section 8 designed to stretch

downward to be inserted into the lobe extrusions 6 formed at the bottom of semi-rigid section 5. Strap 4 also includes a wider, rounded back-of-the-ear section 7 to provide greater comfort without stretching like common elastic rubber bands, which grab and pinch the skin.

[0056] As further shown in FIGS. 1 and 2, continuous strap 4 has a nose bridge arch section 9 and a pair of lobes 10 designed to press down against the wearer's nasal bone area. A plurality of spaced extrusions 13 hold nose bridge arch section 9 to the wearer's preferred location on the nose bridge. A pair of hollow extrusions 12 form a secondary seal in the nasal bone area to inhibit the wearer's

exhalations from escaping towards the eyes. Hollow extrusions 12 inflate with each exhalation to press facemask 1 against the wearer's face.

[0057] As shown specifically in FIG. 2, a pair of spaced holes 11 formed in nose bridge section 9 enable the ready insertion of an eye shield (illustrated in FIG. 10), which contains a pair of matching extrusions. The pull-down action atop the wearer's nose area simultaneously seals the nose section of facemask 1 to the wearer's face while securing the mask and leaning the mask against the wearer's forehead or eyeglasses. FIG. 2 also specifically illustrates semi-rigid section 5 of continuous strap 4, which enables elastic section 8 to be pulled down and secured to lobe extrusions 6.

[0058] FIGS. 1 and 2 also illustrate a chin sealing section 14 of facemask 1, which can be extended backwards to enhance the seal to the wearer's face. Extrusion 15 captures and retains a filter insert (not shown) into facemask 1. An elastic groove 16 captures and seals the filter into the mask frame.

[0059] In FIG. 3, facemask assembly 1A is shown in a front view as including a facemask 1, a plurality of air channels 2 and side vents 3. A continuous strap 4 has a plurality of lobe extrusions 6 extending from semi-rigid section 5, as well as a back-of-the-ear section 7. A more elastic section 8 of continuous strap 4 stretches downward to be inserted into lobe extrusions 6 according to the amount of pressure the wearer wishes to have against the wearer's face.

[0060] FIG. 3 further illustrates continuous strap 4 as having a nose bridge arch section 9 and a pair of lobes 10 designed to press down against the wearer's nasal bone area. A plurality of spaced extrusions 13 hold nose bridge arch section 9 to the wearer's preferred location on the nose bridge. Chin sealing section 14 of facemask 1 can be extended backwards to enhance the seal to the wearer's face. [0061] FIG. 4 specifically shows in a back view of facemask 1 , in which extrusion 15 captures and retains a filter 17 in facemask 1. An elastic groove 16 captures and seals filter 17 within facemask 1.

[0062] FIG. 5 is a side view of facemask 1 with continuous strap 4 unsecured at its nose bridge arch section 9, which is insertable into one of a plurality of spaced extrusions 13 hold facemask 1 to the wearer's preferred location on the nose bridge.

[0063] In the side cutaway view of FIG. 6, filter 17 is inserted into facemask 1. As depicted by arrow 40, bidirectional airflow induces entrained pathogens and particulates to strike filter 17 at an oblique angle. Arrow 30 depicts the channeling by side vents 3 of the wearer's exhalations down and backwards to further protect persons in front of the wearer.

[0064] As further shown in FIG. 6, a pair of hollow extrusions 12 form a secondary seal in the nasal bone area to inhibit the wearer's exhalations from escaping towards the eyes. Hollow extrusions 12 inflate with each exhalation to press facemask 1 against the wearer's face.

[0065] FIG. 7 specifically illustrates, in a bottom view, facemask 1 including lower front vents 2, with no front-facing openings. Side vents 3 direct the wearer's exhalations down and backwards.

Hollowed extrusions 12 form a secondary seal in the nasal bone area to inhibit exhalations from being directed towards the wearer's eyes. Hollowed extrusions 12 inflate against the wearer's face with each exhalation.

[0066] FIGS. 8 and 9 specifically illustrate filter insert 17, which has a frame containing a plurality of air channels 20 in approximate alignment with the air vents of the facemask to facilitate bidirectional air flow to strike the filter at an oblique angle. Filter material 19 can be varied depending upon the particular need of the wearer, such as antibacterial protection or capturing particulate matter. The S-shaped curved section of filter insert 17 increases the capture of airborne pathogens and particles.

[0067] FIG. 10 shows facemask 1 illustrated in FIGS. 1-6 with an exemplary eye shield 21 attached. Eye shield 21 has a pair of interior extrusions 22 that are insertable into a pair of spaced holes formed in nose bridge section 9 (see FIG. 2). Foam strip 23 allows eye shield 21 to rest comfortably against the wearer's forehead.

[0068] FIG. 11 shows facemask 1 with a pair of side resonators 24. Diaphragms within resonators 24 increase the volume and clarity of the wearer's speech. An elastic grooved flange 20 enables the insertion of the diaphragms.

[0069] The present facemask can be manufactured through additive manufacturing methodologies/materials which enable air channeling vents 2 and 3 illustrated in FIGS. 1 and 2 that direct the wearer's inhalation airflow to enter the mask at an oblique angle as well as exhalations to vent downward and backward towards the wearer's neck.

[0070] When describing elements of FIGS. 12-18, the same number is used to identify elements that are the same or substantially similar to each other in the different views illustrated in FIGS. 12-18.

[0071] FIG. 12 is a perspective view taken from the back side of another embodiment of a facemask assembly 101A. Facemask assembly 101A comprises a facemask 101.

[0072] For some applications, facemask 101 can be configured to comprise a biocidal insert 117 for protection against airborne pathogens. Biocidal insert 117 can comprise one-sided or two-sided coverings of the central frame. For other applications, facemask 101 can be configured to comprise filter insert 117 suitable for protection only against particulates such as airborne dust.

[0073] Facemask 101 comprises one or more air vents such as air vent 102 of FIG. 12 for bidirectional flow of air being inhaled and exhaled by the wearer. Vent 102 is configured to direct inhaled air to strike the biocidal insert or filter insert 117 at an oblique angle to enhance the capture and retention of airborne pathogens and/or particulates. Vent 102 is configured to direct exhaled air down and back towards the neck of the wearer. [0074] Facemask 101 further comprises a nose bridge clip 103 described in more detail in reference to FIGS. 15A and 15B.

[0075] Facemask 101 further comprises a continuous strap 104. Continuous strap 104 comprises five contiguous sections labeled AB, BC, CD, DE and EF in FIG. 12. Section AB of continuous strap 104 runs from the start of strap 104, up through the interior of the left side of the head mount pad 105, then forward through a through-hole 11 IB and into the left side of nose bridge clip 103. (Left and right sides are defined from the wearer's perspective.) Section BC of continuous strap 104 spans nose bridge clip 103 of facemask 101, running from the left side of nose bridge clip 103 to the right side. Section CD of continuous strap 104 runs from the right side of nose bridge clip 103 via a through-hole 111 A to the right side of the head mount pad 105. Strap 104 then travels down through the interior of the right side of head mount pad 105, and out through the bottom, and from there forward to chin strap structure 114. Section DE of continuous strap 104 spans chin strap structure 114, running from the right side to the left side. Section EF of strap 104 runs from the left side of chip strap structure 114 via a side hole 118 located at the bottom of head mount pad 105 to the end of strap 104 at stopper knot 109.

[0076] FIG. 13 is a perspective view taken from the front side of facemask assembly 101 A illustrated in FIG. 12. As described above, facemask assembly 101 A comprises facemask 101, vent 102, nose bridge clip 103, continuous strap 104 and head mount pad 105. The elements of facemask assembly 101 A are described in more detail below in reference to FIGS. 14-18.

[0077] FIG. 14A is a side view of facemask 101 illustrated in FIGS. 12 and 13. Facemask 101 comprises vent 102, nose bridge clip 103, continuous strap 104, head mount pad 105, beads 106 and 107, stopper knots 108 (not shown in FIG. 14) and 109, and one or more extrusions 110.

[0078] A part of continuous strap 104 runs from the base of nose bridge clip 103 to the top of head mount pad 105. Another part of continuous strap 104 runs from a chin strap structure 114 (described in detail in reference to FIG. 16) to the bottom of head mount pad 105.

[0079] When strap 104 is in tension, facemask 101 is held fast against the face of the wearer, and head mount pad is held fast against the back of the head of the wearer.

[0080] FIG. 14B is a side view of facemask 101 illustrated in FIGS. 12-14A with alternative cross-strapping 140 indicated by dashed lines. Cross-strapping 140 comprises continuous strap 104 of FIG. 14A rerouted between nose bridge clip 103, chin strap structure 114 and head mount pad 105 as described below.

[0081] A part of cross-strapping 140 runs from the base of nose bridge clip 103 to the bottom of head mount pad 105. Another part of cross-strapping 140 runs from a chin strap structure 114 (described in detail in reference to FIG. 16) to the top of head mount pad 105.

[0082] When cross-strapping 140 is in tension, facemask 101 is held fast against the face of the wearer, and head mount pad is held fast against the back of the head of the wearer. Re-routing continuous strap 104 in the manner described above results in a greater downward tension on the top of facemask 101 and a concomittant greater upward tension on the bottom of facemask 101, which can improve the seal of facemask 101 to the face of the wearer.

[0083] Through-holes 111 A (not shown in FIG. 14B) and 11 IB can be configured to direct strap 104 at an approximately 45° angle below the horizontal. Through-holes 111 A and 11 IB are further illustrated in FIG. 15B.

[0084] FIG. 15 A is a detailed perspective view of nose bridge clip 103 of facemask 101 illustrated in FIGS. 12-14. Nose bridge clip 103 can be configured to provide a compression zone over the nose of the wearer, the compression zone comprising one or more sections of different flexibility. In the embodiment illustrated in FIG. 15 A, nose bridge clip 103 comprises three sections labeled WX, XY and YZ providing two different types of flex.

[0085] Middle section XY can be manufactured from a suitable semi-rigid flexible material. In operation, the wearer positions section XY atop facemask 101 and over the nasal bone area of the wearer's nose.

[0086] Sections WX and YZ can be manufactured from softer, more flexible material than section XY. In operation, sections WX and YZ are generally over the soft tissue area of the upper cheeks of the wearer's face.

[0087] Nose bridge clip 103 further comprises eyelets 112A and 112B, and mounting hole 113. Mounting hole 113 can be used to attach an accessory, for example a face shield or an eye shield.

[0088] Continuous strap 104 is threaded through nose bridge clip 103 and eyelets 112A and 112B as illustrated in FIG. 15 A. When strap 104 is tensioned, it pulls the middle section XY of nose bridge clip 103 against the nasal bone area and the outer sections WX and YZ against the upper cheeks of the wearer's face, thereby creating an effective seal.

[0089] It is a benefit of the present facemask assembly that nose bridge clip 103 can be positioned by the wearer before and during the tensioning of strap 104. An advantage of being able to position nose bridge clip 103, and of facemask assembly 101 A being more adjustable, is an increased likelihood that facemask assembly 101A is more comfortable and effective than conventional facemask

assemblies. Furthermore, nose bridge clip 103 can be manufactured to suit the facial physiology of the wearer. In practice, facemask assembly 101A can be supplied with one or more nose bridge clips and the wearer can select the most suitable nose bridge clip for the wearer's physiology.

[0090] FIG. 15B is a perspective view of a portion of facemask 101 illustrated in FIGS. 12-14 showing detail of nose bridge clip 103. Strap 104 is threaded through nose bridge clip 103, eyelets 112A and 112B, and through-holes 111A and 11 IB. Strap 104 runs from through-holes 111 A and 11 IB to the right and left sides respectively of head mount pad 105 (not shown in FIG. 15B).

[0091] FIG. 16 is a detailed perspective view taken from the underside of facemask 101 illustrated in FIGS. 12-15.

[0092] Facemask 101 comprises air vent 102. Inhaled air is directed up into facemask 101 by vent 102, the inhaled air striking an interior filter 117 (not shown in FIG. 16) at an oblique angle. Exhaled air is directed out of facemask 101 by vent 102, the exhaled air being directed down and back towards the neck of the wearer.

[0093] Facemask 101 further comprises a chin strap structure 114. In some embodiments, chin strap structure 114 can be a tab or another suitable feature into which continuous strap 104 can be clipped. In other embodiments, chin strap structure 114 can be a hole through which continuous strap 104 can be threaded. [0094] It is a benefit of the present embodiment that chin strap structure 114 (in which strap 104 passes under the jaw) can provide an improved seal of facemask 101 to the face of the wearer relative to other embodiments or facemasks in which the strap is at, or above, the jawline.

[0095] Continuous strap 104 as illustrated in FIGS. 12-16 can be hollow medical-grade surgical tubing. Other suitable material can be used, for example O-ring cord or cordage.

[0096] FIG. 17 is a back view of facemask 101 illustrated in FIGS. 12-16.

[0097] Facemask 101 comprises an interior filter 117.

[0098] Filter insert 117 comprises a filter frame. One or both major sides of the filter frame can be covered with biocide material to destroy pathogenic particles. Alternatively the filter frame can be configured to simply provide protection from non-pathogenic particulates such as dust.

[0099] The filter insert can be held in place by tabs 115 and 116 at the top and bottom respectively of the filter insert. Alternatively, the filter insert can be held in place by tabs on the left and right-hand sides, or by another suitable mechanism. [0100] Filter 117 insert can be concave in shape to fit facemask 101, for example, or it can be flat as in facemask assembly 1A described above.

[0101] FIG. 17 illustrates the inward thrust of nose bridge clip 103, the clip being described in more detail above in reference to FIGS. 15A and 15B.

[0102] FIG. 18 is a detailed perspective view of nose clip 103, continuous strap 104 and head mount pad 105 of facemask assembly 101 A illustrated in FIGS 12 and 13 taken from the back side of facemask assembly 101 A.

[0103] Starting at position A in FIG. 18, strap 104 is threaded through bead 106, and stopper knot 108 is used to prevent the end of strap 104 from pulling through bead 106. Strap 104 runs upward through an interior channel of head mount pad 105 and then to position B where it passes through through-hole 11 IB on facemask 101 (not shown in FIG. 18). Strap 104 passes to position C via nose bridge clip 103 and through-hole 111A. From position C, strap 104 runs via head mount pad 105 to position D on the right side of chin strap structure 114 (not shown in FIG. 18). Strap 104 then passes through chin strap structure 114 to position E, and from there back to head mount pad 105. Strap 104 passes through side hole 118 (which, in this example, is on the left hand side) and out through the back side of head mount pad 105. [0104] At head mount assembly pad 105, strap 104 loops around one or more extrusions 110, for example using a figure of eight. Strap 104 is pulled down from extrusions 110 to securely fasten it.

Alternatively, another suitable mechanism (including but not limited to a grip or a clip) can be used to secure the strap at the back of head mount pad 105.

[0105] The end of strap 104 is threaded through bead 107, and stopper knot 109 is used to prevent strap 104 from pulling back through bead 107.

[0106] While facemask assembly 101 A as illustrated in FIGS. 12- 18 has starting position A on the left side of the assembly (when viewed from the back or from the perspective of the wearer), it will be understood that in other embodiments (such as for a left-handed wearer) the starting position A can be on the right side of the assembly.

[0107] In operation, the wearer can adjust facemask assembly 101A as follows. Such adjustment can be done, for example, the first time the wearer dons the facemask assembly.

[0108] First, head mount pad 105 is placed against the back of the head. Secondly, the facemask is placed over the face. Next, the nose bridge clip is positioned over the wearer's nose, and sections AB, BC and CD of strap 104 are tensioned using the right hand to pull section CD through the nose clip and to hold the nose bridge clip fast against the nose. Sections DE and EF of strap 104 are tensioned, this time using the left hand, and by holding the head mount pad in position with the right hand. Once the tension is as desired, strap 104 is looped around extrusions 110 and pulled down to fasten it.

[0109] Once adjusted as described above, the facemask assembly can be readily removed by the wearer, for example, by holding the facemask and lifting the head mount pad forward over the head.

[0110] Since strap 104 is securely fastened, removing the facemask assembly will not significantly affect the tensioning of the strap. The wearer can don the facemask assembly again, without further adjustment, by placing the mask on the face, positioning the nose bridge clip, and then pulling the head mount pad back over the head.

[0111] Head mount pad 105 comprises an opening 119 which can accommodate a pony tail or hair bun.

[0112] It is a benefit of the present invention that the interior air filter (or filter insert) is in close proximity to the nose and mouth of the wearer, thereby providing less opportunity for backflow, build-up of C0₂ within the facemask, and/or re-inhalation of exhaled air by the wearer.

[0113] While particular elements, embodiments and applications of the present invention have been shown and described, it will be understood, that the invention is not limited thereto since modifications can be made by those skilled in the art without departing from the scope of the present disclosure, particularly in light of the foregoing teachings.

[0114] Furthermore, particular elements (such as the chin strap structure, the head mount pad, the nose bridge clip and the like) of the present invention as described in the embodiments above can be incorporated into facemask assemblies in other suitable combinations or arrangements, for example to suit particular applications.

Claims

What is claimed is:

1. A facemask comprising at least one airflow intake in a lower front section thereof, said at least one airflow intake capable of directing inward airflow to strike an interior air filter at an oblique angle.

2. The facemask of claim 1, wherein said air filter is replaceable.

3. The facemask of claim 2, wherein said air filter is biocidal.

4. The facemask of claim 1, wherein the facemask has no directly front-facing openings.

5. The facemask of claim 1, further comprising air channeling features that direct exhalations downward and backward towards the wearer's neck.

6. The facemask of claim 1, further comprising a

continuous strap structure with a semi-rigid lower section extending towards the wearer's ears and a plurality of spaced extrusions with a gap between each extrusion.

7. The facemask of claim 6, wherein said lower strap section extends behind the wearer's ears and a flexible section curves in a semi-circular manner at a common distance.

8. The facemask of claim 6, further comprising an elastic section that extends forward therefrom to complete the continuous strap in front of the wearer's face.

9. The facemask of claim 7, further comprising a nose clip section within a forward-most center section of the continuous strap section and a pair of downwardly-facing lobe extrusions.

10. The facemask of claim 7, wherein a pair of through-holes are formed within a flexible center structure.

11. The facemask of claim 10, wherein said through-holes are spaced equidistantly between said pair of lobe extrusions.

12. The facemask of claim 1, further comprising a pair of hollowed extrusions along the topmost interior rim on either side of the curved topmost section.

13. The facemask of claim 1, wherein the facemask has a pair of flexible circular openings formed on either side of the wearer's mouth and having interior channels suitable for mounting at least one resonating diaphragm.

14. The facemask of claim 10, further comprising a transparent eye shield comprising a pair of extrusions insertable into the pair of through-holes such that said eye shield is secured to the wearer's nose area and inclined inward to rest the top portion against the wearer's forehead.

15. A facemask comprising:

(a) at least one air vent for bidirectional flow of air being inhaled and exhaled by the wearer, said at least one airflow intake capable of directing inward airflow to strike an interior air filter at an oblique angle;

(b) a head mounting pad having a single pull to tension the facemask against the wearer's face;

(c) a continuous strap positionable under the chin of the

wearer;

(d) a nose bridge clip positionable by the wearer before and during the tensioning of said strap.

16. The facemask of claim 15, wherein said air filter is replaceable.

17. The facemask of claim 15, wherein said at least one vent is a plurality of vents.

18. The facemask of claim 15, wherein said vent is

configured to direct exhaled air downwardly and backwardly towards the neck of the wearer.

19. The facemask of claim 15, wherein said nose bridge clip is configurable to provide a compression zone over the wearer's nose, said compression zone comprising portions of differing flexibility.

20. The facemask of claim 15, wherein said head mounting pad has an opening formed in an interior portion thereof.