Barrier with Medical Frame and Exhaust-Type Face Mask

Abstract

The claimed inventions relate to personal protective equipment, and specifically to masks primarily intended for use in the medical field. The technical result of the claimed inventions is to improve the working conditions of medical personnel throughout the use period of the mask, while providing complete protection against the ingress of any liquid medium and infection into the respiratory tract, both from the operating room and to the patient, as well as complete protection for the user against droplet infection in public places. A barrier-exhaust medical mask with a frame includes a hollow frame designed in the form of channels that form a mask cavity for the lower face and include an inlet and an outlet for airflow. The transparent outer surface of the frame is airtight, and the side adjacent to the face surface is made of an elastic airtight fabric. The frame includes a nose shield cover portion and forms a mask cavity for the mid-face section. [Selection diagram] None

Description

Technical Field

[0001] The group of inventions claimed relates to personal protective equipment for humans, namely face masks intended mainly for use in the medical field.

[0002] The invention is presented in three versions: · General environmental and hygienic protection for both surgeons and patients during any level of complexity of medical assistance, including long-term surgical procedures; · Personal protection for the general public against airborne infections including influenza.

[0003] The differences between the versions of the medical face masks are presented by their main application areas: general, surgical, or clinical.

[0004] In contrast to medical filtering masks, these relate to barrier-type and exhalation-type face masks, i.e., those that completely prevent the passage of exhaled air and the expulsion of exhaled breath in the intended direction. Structurally, each version of the mask is a hollow frame.

Background Art

[0005] Various options for the design of medical barrier face masks and face masks with frames are available from the background art.

[0006] From the literature (the journal “Surgery Reporter n.a. I.I. Grekov” No.12, 1969, authors: academician of the Academy of Medical Sciences, prof. S.M. Kurbangaleyev et al.), a surgical barrier face mask is known, which is made of rigid plastic as a textured shield that fits snugly to the face. The mask has been tested during 2,000 surgical procedures by the First Leningrad Institute (the First Saint Petersburg State Medical University) n.a. academician I.P. Pavlov, demonstrating its exceptional aseptic properties. The indisputable advantages of the barrier face mask (in the form of an airtight shield) have been experimentally and clinically proven by comparing it with a filtering (standard medical) mask regarding the efficiency of patient protection against respiratory infections during surgical procedures.

[0007] The disadvantages of a given design are as follows: - A large amount of exhaled air remains in the under-mask area, causing the face to become overly moist and hot - a greenhouse effect occurs, leading to an overall unpleasant feeling and a decrease in the surgeon's productivity; - It has a rigid structure that fits snugly to the face area over a long period.

[0008] Despite providing a high level of patient protection during surgical procedures, the above-mentioned disadvantages have a significant impact on the surgeon's performance by reducing it to an unacceptable level, so this type of mask is not used in medical practice.

[0009] A breathing face mask is known from the document CN2162260Y published on April 20, 1994, which is intended for breathing through the nose and mouth. It consists of two box-shaped side frames with through holes and integrated into an integral structure, and a rigid shield located between them on the front side of the nose-mouth area. The mask is functionally divided into a front sector, a right sector, and a left sector, where the left and right sectors represent side containers for inserting filter elements. All exhaled air is removed through valves (similar to a ventilator), and the inhaled air is filtered. A partition placed between the containers serves as a partial barrier (shield) function to protect the surface of the face against moisture penetration from the outside.

[0010] The disadvantages of the given design are as follows: - There is little natural ventilation in the area under the mask, and high levels of CO₂ and moisture will accumulate, which will gradually reduce the health status of the wearer; - A large number of filter elements cause a high breathing resistance, which significantly affects the performance of the wearer; - It is a rigid structure that fits tightly to the face area for a long time.

[0011] This overall disadvantage is inherent in both analogues.

[0012] The tightness of the rigid and inelastic structure with the surface of the face, aiming to ensure the necessary occlusion, will compress nerve fibers and blood vessels for a long time, which will cause pain, local sensory abnormalities, and significant discomfort, thereby making this type of mask practically unusable.

[0013] As the closest analogue, the applicant has selected the following source of information: Russian Patent No. 2240160 of November 20, 2004, from which a barrier-exhaust face mask with a medical frame is known.

[0014] Similar to the claimed version of the present invention: · Structurally, the mask is a hollow frame; · The outer part of the frame is made of an air-impermeable material (medical plastic). The inner part (which contacts the face surface) is made of a soft elastic fabric, which prevents compression of the facial nerve fibers and blood vessels by the mask; · Performs a barrier function and an exhalation function; · Does not cause respiratory resistance.

[0015] Some essential features distinguish the frame of the claimed invention from analogues: · By fitting snugly to the face surface, its bottom section and central section (according to the classification by R.A. Reiss): cover from the chin to the level of the nasal bridge; · The sub-mask space forms a uniform nasal-oral cavity. · The facial (inner) part of the frame has coupling cutouts around the nasal and oral regions;

[0016] The disadvantages of the given design are as follows: - In the large sub-mask area (mainly during mouth breathing), excessive accumulation of moisture occurs and the CO2 level rises, which partially reduces the surgeon's performance; - The physiological differences in human breathing via the nose or mouth are not taken into account, which inappropriately reduces the hygienic performance of the mask; - Similar to its analogues, since the shape of the mask depends on the facial surface undulations, the mask is not universal, which reduces its consumer-oriented attributes; - Wearing the mask hinders the movement of the lower jaw, thus reducing the possibility of taking communication - interfering with conversation.

Summary of the Invention

[0017] A decline in a surgeon's performance during a surgical procedure as a result of a sudden deterioration in breathing conditions with a medical filtration mask significantly affects the quality of the surgeon's work. Moreover, generally, medical filtration face masks lose their protective properties after 30 minutes of use. As a result, relatively inaccurate surgical procedures and a high level of postoperative complications can be observed worldwide.

[0018] Due to their design features, standard medical filtration masks lack the possibility of protecting the general population, which is of utmost importance during an epidemic, from viral infections and numerous dangerous bacteria.

[0019] By creating an impermeable barrier against airborne infections without interfering with the user's breathing ability, different protection principles are proposed for patients and the general population. Furthermore, several other major problems are solved, which leads to, for example, preserving the performance of medical staff throughout their working hours.

[0020] The aim of this group of inventions of medical face masks is to eliminate the deficiencies of the prior art and to achieve the following results: - Elimination or significant reduction of CO₂ accumulation in the space under the mask and prevention of an increase in moisture and temperature levels, i.e., solving the basic hygiene problems of the prototype; - Implementation of various methods of protection against airborne infections that are consistent with the environmental conditions and the nature of the wearer's work; - Improvement of comfort and efficiency when using the mask due to the effectiveness of their protection during mouth or nose breathing; - Reduction of the accumulation of airborne infections in a confined space (e.g., an operating room) by complete or partial neutralization of airborne infections inside the mask compared to analogues and medical filtration masks; - Universality is achieved since the shape of the mask does not depend on the relief of the face surface; - The mask does not interfere with the mobility of the lower jaw, i.e., it does not affect the wearer's communication ability.

[0021] The technical results of the group of inventions claimed are: · Improvement of the working conditions of medical staff throughout the entire period of using the mask, in a state of complete protection against any liquid media and infection entering the respiratory system both from the surgical field and towards the patient; In a literal translation that hardly distorts its meaning, here it actually means: "Improvement of the working conditions of medical staff throughout the entire period of using the mask, in a state of complete protection against any liquid media entering the user's respiratory system and infection in the area of the surgical field, both from the surgical field and from the consumer / surgeon." · Complete protection of the wearer against airborne infection in public places, and · Protection of the human respiratory organs from an erosive environment in different specialized areas of activity without any loss of productivity.

[0022] The results of the claimed technology are achieved by embodiments of the design of a medical face mask with three options, each of which, while having new consumer-oriented attributes, complements or builds on the performance of the previous option.

[0023] All mask options have one common inventive concept; namely, they include a hollow frame that forms a space under the mask for the lower part of the face, and the hollow frame is made in the form of a channel with an airtight outer surface and an inner surface (closest to the face surface) made of a breathable fabric. The frame channel includes, on each side (left and right), an air inlet and an air outlet for the air flow formed during inhalation / exhalation. Generally, the side in contact with the face surface has a notch around the mouth.

[0024] Structurally, various functional spaces are formed inside the mask: an area for mouth breathing and an area for nose breathing. In the mouth area (lower part of the face), each version of the mask is made in the form of a hollow frame. In the central part of the face (nose area), depending on the version, a separate zone for nose breathing is formed, which may be open, semi-open, or closed.

[0025] All versions are fixed to the head area by standard means: by straps, rubber bands, etc.

[0026] The face mask is positioned on the head so that almost all exhaled air is expelled to the rear, into a safe area for people around the wearer.

[0027] By separating the mask space into two relatively independent zones, optimal conditions for breathing are achieved, taking into account the physiology of nasal and oral breathing. The presence of a cavity within the frame ensures additional ventilation and regulation of the space under the mask.

Brief Description of the Drawings

[0028]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0029] Medical face mask, option 1 The face mask is general-purpose, i.e., it is intended to be used by the general population as well as in medical institutions. It may be applied as the basic version (the simplest one) or as a combination of a frame mask and additional components.

[0030] Unlike the prototype, the mask frame covers the lower part of the face and provides complete protection only against the oral area - the main source of airborne infection and the entry point of external infections. To maximize the wearer's ability to perform, nasal breathing is left completely unobstructed, which is particularly important for healthy wearers with undamaged nasal mucosa. To minimize breathing resistance, the sides of the mask frame are extremely short compared to the prototype.

[0031] The hollow mask frame consists of two parts, which form its outer surface and the inner surface that directly contacts the face surface. Since the outer part of the frame is made of airtight and generally transparent medical plastic, it improves the wearer's communication ability. If the transparency of the mask is irrelevant, its outer part is made of, for example, dense cloth or paper. The inner part of the frame, i.e., the side surface that contacts the face surface, is breathable and is generally made of an elastic fabric, such as a spunbond fabric or medical gauze. In order to reduce the total breathing resistance, the notch around the mouth area can be arranged on the side surface that contacts the face surface. If a fabric with low breathing resistance is used inside the frame (for example, single or double gauze), the notch in the mouth area is not appropriate.

[0032] For the convenience of transportation, the mask may have a special device for folding it: from a three-dimensional to a flat shape. For example, the outer part of the frame may have folding parts in the form of pleats or gathers. In this design, the mask is folded and takes shape as a result of forced exhalation.

[0033] In its basic version, the mask (with no additional components) is mainly targeted at the general public, for example, to prevent the spread of influenza epidemics in public places.

[0034] The additional components of the mask expand the scope of application to include medical facilities in order to enhance its protective properties.

[0035] For experts to better understand all aspects of the disclosure of the nature of version 1 of the claimed technical solution, further explanation is given with reference to FIG. 1 showing the designated positions of the structural parts.

[0036] FIG. 1 shows the design of version 1 of the medical barrier - exhalation face mask.

[0037] The mask frame for the lower part of the face includes an air-impermeable outer surface 2 (shown in a perspective view) of a plastic frame. For example, through its outer surface, the breathable inner surface 3 of the frame can be seen. This is made of, for example, fabric and can come into contact with the surface of the face. A notch 4 is provided around the mouth area. The frame forms lateral air holes (inlets / outs) 5 on both sides of the head, i.e., on both lateral heads, for the passage of air flow.

[0038] The nasal area is completely open, i.e., inhalation and exhalation through the nose are not obstructed. The upper edge of the frame passing just below the nose, due to its geometric shape, partially expels the air exhaled from the nose.

[0039] When inhaling through the mouth, the outside air enters the frame cavity through the lateral air holes 5 and then passes through the notch 4 on the side surface 3 that comes into contact with the surface of the face. If there is no notch, it passes through the breathable fabric.

[0040] During exhalation through the mouth, the air is first supplied to the frame cavity and then expelled through the lateral air supply openings 5. Since the outer surface 2 of the frame is air-impermeable, the exhaled air, along with any moisture contained therein, is directed entirely backward - in the opposite direction. The side surface 3 of the frame that comes into contact with the surface of the face, due to its elasticity and hygroscopicity, prevents compression of nerve fibers and blood vessels in the facial area, does not cause discomfort or pain, and prevents humidification (maceration) of the facial area.

[0041] To extend the protective properties of the mask version 1, the following additional components are used.

[0042] 1. A breathable material 6 extends beyond the frame and includes an additional device 7 for partially retaining the moisture contained in the exhaled air. The device 7 is made in the form of a folded part or strip of fabric and, for example, can be immersed in a special disinfectant if necessary. There can be several of these devices 7 on both sides of the mask.

[0043] 2. The air inlets and outlets, i.e., the side air openings 5 of the frame, include additional components 8 in the form of spoilers on their outer (ventilated) parts, which direct the exhaled air towards the material 6 in contact with the surface of the face. This includes additional devices 7 that extend beyond the frame and partially retain the moisture contained in the exhaled air. The spoiler may be an extension of the outer surface 2 of the frame or a separate part that can be attached, for example, with glue, adhesive tape, etc. The spoiler can be made of a material with special properties, such as bactericidal, adhesive, etc.

[0044] The breathable material of the mask may be single-layer or consist of several layers, each of which may have various useful properties, such as bactericidal action against different types of microorganisms, etc. All the materials applied (to each of the layers) are the same as those widely used in medical operations and have appropriate approvals.

[0045] The plastic and fabric parts of the mask can be joined (sewn, glued) in the factory or connected by the wearer himself / herself, for example, using adhesive tape.

[0046] The mask is attached / fixed to the wearer's head area using devices 9, such as strings, straps, rubber bands, etc.

[0047] Medical face mask, Option 2 This version of the mask is mainly intended for use in surgeries and boasts maximum protection for doctors and patients under surgical conditions. It aims to preserve the working ability of medical staff to the greatest extent.

[0048] This option is a combination of two types of masks: a frame and a shield style that form two different mask spaces: a lower frame for the oral region and a shield for the nasal region. A partition is formed between the shield and the frame, including an air opening for air breathed through the nose to pass into the frame cavity. In this opening, a valve can be installed, if necessary, to direct the air breathed through the nose towards the frame and prevent any air from entering the space under the mask through the mouth.

[0049] Since the shield is airtight and placed slightly away from the surface of the face, nasal breathing remains virtually unobstructed.

[0050] The main purpose of the mask shield is to direct (by its aerodynamics) the air breathed out of the nose directly into the cavity of the frame, which completely prevents it from reaching the surgical field. This solution allows the surgeon to maintain a high quality of the main (nasal) type of breathing while enhancing the surgeon's performance during the operation.

[0051] Structurally, the partition between the shield and the frame may not have an air opening, but in this case, the aerodynamics of the air flow regulated by the shield become completely irregular, which significantly reduces the consumer-oriented attributes of the mask.

[0052] Furthermore, the shield protects the nasal region from external pathological factors during the operation: biological fluids, airborne infections, etc., and also partially protects the central part of the face. This also relates to enhancing the safety of the surgeon.

[0053] During the operation by the surgical team, the air breathed by the medical staff is completely discharged into the non-sterile area of the operating room, in contrast to a filtering mask. This ensures a high level of sterility of the surgical area itself, i.e., contributes to a reduction in the risk of postoperative complications. Therefore, the overall quality of the treatment provided by the medical facility is improved.

[0054] For the expert to better understand all aspects of the disclosure of the nature of the claimed technical solution according to version 2, further explanation is provided with reference to FIG. 2 showing the designated positions of the structural components.

[0055] The frame of the mask located at the lower part 1 of the face includes an outer airtight part 2 of the frame (shown in the perspective view), which can be made of, for example, plastic, and through its outer surface, the breathable inner surface 3 of the frame can be seen. This is made of, for example, a fabric material and has cutouts 4 around the mouth area. The frame forms lateral air holes (inlets / outs) 5 for the passage of air flow on both sides of the head.

[0056] In contrast to Option 1, in order to discharge exhaled air as far as possible away from the surgical field, both side parts of the frame are made as long as possible.

[0057] The frame also has an air-impermeable shield 10 covering the lower part of the nose. There is a partition 11 with air openings provided between the shield 10 and the frame. The partition may have a plurality of similar openings, which may be the same or take various shapes.

[0058] FIG. 2 shows that since the shield 10 is arranged at a certain distance from the surface of the face, it forms a slot-like space.

[0059] When inhaling through the nose, air freely enters through this slot-like space. When exhaling through the nose, all air is directed from top to bottom through the air openings in the partition 11 due to the aerodynamic characteristics of the shield. The air enters the frame cavity and then exits through the lateral air openings 5 (inlets / outs) for passing the air flow.

[0060] Mouth breathing is performed in the same way as Option 1. One or more valves can be installed in the air openings in the partition 11 to completely eliminate the air entering the space under the mask in the central part of the face from the frame cavity (if necessary).

[0061] However, when the inner cavity of the frame is made to take into account the aerodynamics of the air flow passing therethrough, the relevance of the valve is reduced or removed.

[0062] Medical face mask, option 3 The main purpose of this version of the mask is for general clinical use. The mask can be recommended for use in all types of medical institutions, including the infectious disease department, and for the provision of all types of medical care from outpatient patients to infectious disease surgery. It aims to maximize the protection of medical staff without significantly impairing its performance capabilities. A specific feature of this mask option is its ability to deform to fit specific working conditions of medical staff.

[0063] The design of this type of mask is a hybrid consisting of three types of masks: a frame, a shield style, and a filter, i.e., filtration. Thus, it combines the functions of all types of well-known medical masks: barrier - exhalation, barrier, and filtration.

[0064] The basic differences between option 3 and the first two options are as follows: 1. The mask can have two states: initial and working. In the initial state, the mask is, in fact, no different from option 2 in terms of functionality.

[0065] In this state, breathing is not obstructed. Therefore, at a similar position, for example, it can be used in conventional surgical procedures. When there is a risk of infection, the mask can be converted to the working state, i.e., all airflows generated during inhalation and exhalation through the mouth and nose are directed through the built-in filter. For example, when a medical worker moves from a clean zone to an infected area, a similar risk exists. When leaving that area, there is no risk of infection, and the mask is returned to its initial state, where the conditions for breathing are significantly improved. During an emergency operation (in case of an emergency), it is often found immediately that the patient has a complication of an infectious disease. In this situation, the surgeon can switch the mask to its working state without interrupting the operation and without removing the mask, i.e., the surgeon can be quickly protected.

[0066] 2. The hollow frame for the lower part of the face is divided into three functionally different sectors: the central sector and two side sectors.

[0067] 3. The outer wall of the side sector of the frame is an air filter made of a material used in the production of standard medical (filtration) masks, such as spunbond fabric.

[0068] 4. The side walls of the frame may be homogeneous or consist of continuously connected segments, each of which can be a filter of different density, i.e., a filter designed for different types and levels of infection.

[0069] 5. The channel of the frame has a device for closing it and can be opened again to direct the airflow during inhalation and exhalation through either the inlet / outlet (side opening) or the built-in filter.

[0070] 6. When the side walls of the frame consist of a plurality of segments, each segment can have a separate device for closing it, which can be made, for example, in the form of adhesive tape or a special latch.

[0071] 7. The mask shield is generally made entirely of the filter material used in standard medical masks or, if it needs to have aerodynamic properties, consists of a combination of an air-impermeable material and a filter fabric. Similar to Option 2, the shield does not contact the surface of the face.

[0072] 8. A device is incorporated around the edge of the shield fabric to ensure a snug fit to the contour of the face around the nasal bridge. This can be, for example, an adhesive strip, a ductile wire, an elastic bracket, etc.

[0073] 9. There is a partition between the frame and the shield that separates the two mask sub-spaces and can be made without air openings, in contrast to Version 2. If the shield is made entirely of fabric, its aerodynamic properties are not relevant. At the same time, during operation, the absence of air openings in the partition provides a higher level of protection for the mask.

[0074] For the experts to better understand all aspects of the disclosure of the nature of the technical solution claimed by Version 3, further explanations are provided with reference to FIG. 3 showing the designated positions of the structural components.

[0075] FIG. 3 shows the design of the third medical barrier - exhaust face mask.

[0076] The frame of the mask located at the lower part 1 of the face includes the outer airtight part 2 of the frame (shown in the perspective view), which can be made of, for example, plastic, and through its outer surface, the breathable inner surface 3 of the frame can be seen. This can be made of, for example, a fabric material and has cutouts 4 around the mouth area. The frame forms lateral air holes (inlets / outs) 5 for the airflow on both sides of the mask.

[0077] This mask version can be used in two states: initial (open) and working (closed).

[0078] In the initial position, the shield 10 is not in contact with the surface of the face, and the inlet / outlet 5 is open to allow the air flow to pass through.

[0079] In Figure 3, the medical mask version 3 is shown in the working (closed) state.

[0080] Generally, the shield 10 made of a single filter material (e.g., spunbond fabric or medical gauze) fits perfectly to the contour of the face around the nasal muscles. As a result, the mask space in the nasal region is completely closed, and inhalation / exhalation through the nose is performed through the filter fabric of the shield. A partition 11 is formed between the shield and the frame, which, unlike version 2, may not include an air opening.

[0081] The outer surface of the side section of the frame, unlike options 1 and 2, consists of a segment 12 (side filter) made of filter fabric. The walls of each segment 12 may consist of filters of fabrics with different densities or different numbers of layers (e.g., spunbond fabric). A device 14 for closing the channel is arranged at the outer boundary 13 of each segment (shown only for the central segment). As a result, during inhalation / exhalation through the mouth, the air passes only through the side filter 12.

[0082] To preserve the framed structure (air channel) of the side segments of the frame, a forming support (e.g., a coarse nylon mesh) can be installed between the fabric layers of its outer part. The mesh can be woven into the fabric in the form of individual fibers, or the fabric itself in the form of a mesh can be immersed in a forming solution (e.g., starch).

[0083] The breathable material of the frame, the filter in the side segments, and the shield can be made of fabrics with different functional properties or the same fabric (used as a standard in medical operations).

[0084] In versions 2 and 3 of the mask, unlike the prototype, the shield does not contact the face surface in the area of the nasal muscles. The resulting gap is used not only to supply air during nasal inhalation, but also to allow free movement of the plastic part so that it can follow the movement of the lower jaw.

[0085] Therefore, the connection between the mask parts does not interfere with the free movement of the lower jaw, thereby enabling, for example, communication during surgery. In Option 3, the shield 10 is made of a fabric with some slack so as not to interfere with the movement of the lower jaw during conversation.

[0086] Each version of the mask may have various additional devices or features and may be made of different materials or using different techniques.

[0087] For example: For additional protection in the area around the eyes and the rest of the face surface area, the plastic part of the mask may have an additional structure in the form of a transparent shield.

[0088] To enhance communication ability, the outer surface of the mask is completely or partially transparent; it may be made of plastic as shown in Figures 1 - 3. Taking into account the design purpose, the plastic may be of different colors and various inscriptions and images may be printed on it. The plastic may also be non - transparent (using any color combination).

[0089] For additional ventilation, the outer surface of the frame in front of the mouth area may be a movable wall in the form of a membrane that can vibrate in synchronization with breathing.

[0090] The part of the frame that contacts the face surface may be made of, for example, cotton fabric, or a transparent or semi - transparent natural fabric (such as silk, batiste, chiffon, etc.), or a solid fabric or net (fine or coarse mesh) from synthetic polymers (such as nylon, capron, etc.).

[0091] Components for shaping and reinforcing the mark (such as meshes, threads, rubber bands, and straps that perform the function of the mask strings) can pass through the layers of the breathable material in order to increase strength and better conform to the surface of the face.

[0092] Since frames are present in all versions of the mask, various devices and equipment can be installed within its channels to additionally process the air used for breathing (such as cleaning, drying, sterilizing, cooling, heating, deodorizing, etc.).

[0093] By considering the different characteristics of the airflows formed during inhalation / exhalation by mouth or nose breathing, the mask frame cavity can include at least one device, such as one or more partitions, air channels, etc., for the optimization and separation of the airflows.

[0094] At least one filtering component can be installed along the air flow path within the frame channel, which can be further treated, for example, with a disinfectant, or can be developed with a filtering material (such as spunbond fabric) used in the manufacture of medical masks.

[0095] Furthermore, at least one air channel within the mask frame can include at least one moisture absorption element.

[0096] Any air channel within the mask frame can include at least one inlet or outlet valve.

[0097] At least one tube for forcibly supplying an air mixture from an external source to the respiratory organs and / or for forcibly discharging exhaled air from the space under the mask can be attached to at least one air channel within the mask frame.

[0098] At least one air channel within the mask frame may further include at least one compressed air bottle and can improve the composition of the inhaled air under stand-alone mode conditions or on-site (combat) conditions.

[0099] At least one air channel within the mask frame may also include at least one fan.

[0100] At least one air channel may be formed in a spiral shape, thereby moving foreign matter in the inhaled air rotationally (centrifugally) and attaching it so as not to move to the wall of the channel.

[0101] At least one air channel within the mask frame may include at least one zero-resistance filter.

[0102] The inner surface of the frame channel may be treated with a special adhesive that promotes the surface adhesion of dust and various biological aerosols contained in the air.

[0103] The mask frame may further be electrostatically treated to ensure the surface sedimentation of dust particles and other foreign matter contained in the passing air stream and may be made to possess an opposite electric potential.

Claims

Claim 1: A medical mask comprising a frame configured to cover the lower part of the user's face below the level of the user's nose, wherein the frame has a channel formed between an outer surface and an inner surface of the frame, the channel including at least one inlet and at least one outlet for air to pass from and to the user's mouth, the outer surface being air-impermeable, the inner surface configured to contact the surface of the face being made of a breathable material, the frame having an opening disposed near the user's nose, such that air exhaled from the user's nose flows at least partially through the opening into the channel. Claim 2 The medical mask according to claim 1, wherein the inner surface has a notch configured to be disposed around the mouth. Claim 3 The medical mask according to claim 1, wherein the inner surface extends beyond the outer surface. Claim 4 The at least one inlet and / or outlet includes additional components configured to direct exhaled air towards the inner surface, the medical mask according to claim 1, wherein the components extend beyond the outer surface. Claim 5 The medical mask according to claim 3, wherein the inner surface extending beyond the outer surface includes additional means for retaining moisture in exhaled air. Claim 6 The medical mask according to claim 1, wherein the outer surface of the frame has folds in the form of pleats. Claim 7 The medical mask according to claim 1, further comprising at least one device for attaching the medical mask to the head region. Claim 8: The medical mask according to claim 5, wherein the means for retaining moisture comprises a water-absorbent fabric. Claim 9: The medical mask according to claim 1, further comprising at least one filter for filtering at least one of inhalation or exhalation. Claim 10: The medical mask according to claim 9, wherein the filter is configured to filter the air at the inlet. Claim 11: The medical mask according to claim 9, wherein the filter is configured to filter the air at the outlet. Claim 12: Comprising a shield covering at least the lower part of the user's nose The shield is fluidly connected to the frame via a partition including the opening. The medical mask according to claim 1, wherein the partition enables the user to exhale from the nose to the frame. **Claim 13**: The medical mask according to claim 12, wherein the partition has a valve configured to allow air to flow from the shield to the frame while preventing air from flowing from the frame to the shield. **Claim 14**: The medical mask according to claim 1, wherein the breathable material includes a hygroscopic material. **Claim 15**: The medical mask according to claim 12, wherein the highest point of the shield is disposed above the user's nostrils. **Claim 16**: The medical mask according to claim 1, wherein the at least one inlet has an inlet valve. The medical mask according to claim 1, wherein the at least one outlet has an outlet valve.

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