Abstract: A modular helmet-mask assembly for protecting a user's head and face from hazards such as from chemical and biological warfare agents. The invention includes an impact resistant helmet; a face protection assembly, which can be attached and detached from the helmet; and a transparent, impact resistant lens. The face protection assembly includes an impact resistant face protection shell with a vision port, through which the transparent lens can be positioned; a flexible nosecup assembly positioned to engage the mouth and nose of the user, which also includes a breathe-through airflow assembly and filter unit; and a flexible face seal which surrounds the nosecup assembly and lens and engages the face of the user. An adjustable head harness is attached to the shell or face seal, for adjustably securing the face seal and nosecup to the user's face to maximize comfort and protection while preventing fogging of the lens.

Abstract: A headgear article includes a head covering member that has an opening formed therein. A panel is disposed over the opening and is removably attached to the head covering member. A respirator system is also disclosed that includes the headgear article and further including a visor and defining an interior zone. The respirator system also includes a clean air supply system having an inlet configured for connection to a source of clean air and an outlet disposed within the interior zone.

Abstract: A heat management system for industrial safety equipment is described, including an industrial safety article (e.g., a full face respirator), a power source and a fan unit, wherein the fan unit is mounted on the industrial safety article such that the fan directs air within a confined or other interior space of the industrial safety article, and wherein the fan unit is powered by the power source.

Abstract: An adjustable mask apparatus for use in a breathing assistance system may include a housing, an adjustment arm, and a locking member. The housing may support a cushion configured to provide a seal against a patient's face. The adjustment arm may include a first end configured for attachment to a head gear, and a second end rotatably coupled to the housing to allow rotation of the adjustment arm to adjust a distance between the first end of the adjustment arm and the patient's head. The locking member may be coupled to the housing and may be configured to secure the adjustment arm in one of a plurality of predetermined rotational positions, each predetermined rotational position comprising a rotational position of the adjustment arm with respect to the housing.

Abstract: Mask apparatus and methods for providing positive airway pressure therapies are disclosed. The mask apparatus includes a mask secured to the mount with the mask cantilevered from the mount. A circumferential band, a first lateral stabilizing band and a second lateral stabilizing band secure the mount to the head of a user. The methods include securing a mask apparatus to the head of a user and administering a positive airway pressure therapy.

Abstract: A firefighter's fire resistant hood designed for attachment to a firefighter's fire resistant mask using a fastening means to form a seal between the firefighter's fire resistant hood and firefighter's fire resistant mask thereby preventing injury to the firefighter's head, face, neck, shoulders and back. The firefighter's fire resistant hood comprises a head portion and a shoulder portion. The head portion has a face opening. The inner periphery of the face opening contains a securing means to interface with another securing means on the mask element thus removably attaching the two elements.

Abstract: A helmet (12) includes a thermoelectric heat pump (14) mounted onto a rear surface of the helmet shell (12) for delivering temperature conditioned air to the interior of the helmet shell. A multi-layer structure (48) on the helmet shell interior distributes conditioned air across the scalp and directly onto the face. An optional scoop (38) directs ambient air to the heat pump (14). Another version locates the heat pump (68, 84) remotely and conditioned air is transmitted to the helmet apparatus (70, 78) via a flexible conduit (72, 85).

Abstract: A respiratory component mounting assembly includes a first respiratory component, a second respiratory component and a mounting clip for mounting the second respiratory component to the first respiratory component. Each of the first and second respiratory components includes at least two spaced apart clip openings. The mounting clip has an intermediate portion and two spaced apart free ends connected to the intermediate portion. The intermediate portion of the mounting clip is received within both of the clip openings of the first respiratory component and the free ends of the mounting clip are received in the clip openings of the second respiratory component for releasably securing the first and second respiratory components together.

Abstract: A respirator helmet (10?) or other helmet adapted to receive, by means of a plug (66) and socket arrangement (70), a pivotable bar (62) carrying a protective screen (63) such that the screen may be moved between a lowered position in front of the face of the wearer of the helmet and a raised position.

Abstract: A protective device comprising a mask part, which covers the wearer's mouth and nose and is provided with elements through which air can be supplied inside the mask part to enable breathing. To eliminate problems caused by draught, the mask part is provided with a wall portion, which is arranged to extend from the edge portion of the mask part against the wearer's face inside the mask part so that an interspace connected to the inner space of the mask part is formed between the wall portion and the inner surface of the mask part and that the elements through which air for breathing can be supplied inside the mask part are arranged to open into the interspace.

Abstract: An apparatus including a lens, a gasket to receive the lens and a frame removably coupled to a respirator helmet is defined. The gasket forms a seal with a respirator helmet. The frame secures the lens within the gasket and defines a release mechanism to enable a quick release of the frame from the respirator helmet.

Abstract: A coating composition that is incorporated into a facemask to reduce fogging and glare is provided. For example, in one embodiment, the facemask contains a shield or visor formed from a transparent substrate having at least one surface applied with the coating composition of the present invention. The present inventors have unexpectedly discovered that one or more water-soluble organic polymers, such as ethyl hydroxyethylcellulose, may be utilized as a principal component of the coating composition to reduce fogging and glare in a simple, yet effective manner.

Abstract: A respirator for a compressed air breathing apparatus including a lung machine controlled by a control membrane and an expiratory valve with an air outlet. The air outlet of the expiratory valve and the control membrane of the lung machine are covered by a common lid spaced from the expiratory valve and control membrane, with there being at least one air discharge opening on the lid that forms a purging space around the control membrane through which air from the air outlet passes so as to move against the control membrane and to the at least one discharge opening.

Abstract: The present invention provides a system for a gas delivery and monitoring system for delivering a gas product to a patient and receiving a gas product exhaled from a patient. In an embodiment, the gas delivery and monitoring system includes a head support made of resilient material and having therein a facial cavity. The facial cavity is configured to fit the contours of a patient's face and provides an oxygen rich environment for the patient while undergoing a medical procedure. In an embodiment, the facial cavity is shaped substantially in the form of a figure eight. In an embodiment, the facial cavity is further provided with one or more segmented edges that can be removed to further shape the facial cavity to the contours of the patient's face. In an embodiment, tubing is used to deliver oxygen from an oxygen source to the patient. Similarly, tubing is also used to receive carbon dioxide exhaled by the patient so that it might be measured by a carbon dioxide monitor.

Abstract: The invention concerns a protective headgear comprising a respirator (2) capable of being connected to a breathing mixture source, an eye protecting shield (5) and first (32) and second (56) lock elements, respectively located on the respirator (2) and on the shield (6) and adapted to co-operate with each other to secure the shield (6) to the respirator (2), when the respirator is in its use position on the user's face, the first (32) and second (56) lock elements being adapted to be mutually engaged and interlocked by a movement bringing the shield (6) closer to the respirator (2), from above.

Abstract: An adjustable mask provides a unique configuration, whereby one hand may be used to both doff the respirator and to securely don the mask. In one embodiment, such configuration is facilitated by a reel attached to one or cords, the cord attached at a second end to a harness designed to engage a portion of the head. Rotation of the reel in one direction causes the one or more cords to tighten, while rotation of the reel in an opposite direction causes the one or more cords to loosen.

Abstract: A respiratory mark assembly for delivering breathable gas to a patient includes a frame and a cushion. The cushion has a non-face contacting portion structured to be connected to the frame, a face-contacting portion structured to engage the patient's face, and an intermediate portion that interconnects the non-face contacting portion and the face-contacting portion. The intermediate portion includes a gusset portion that applies a first component of force to the patient's face through the face-contacting portion. A spring structure is coupled with the face-contacting portion of the cushion. The spring structure applies a second component of force to the patient's face through the face-contacting portion. The first and second components of force applied by the gusset portion and spring structure, respectively, determine a contact force of the cushion applied to the patient's face through the face-contacting portion. The intermediate portion may also include an elastic cuff portion.

Abstract: Disclosed is an air supplying device for a welding mask, capable of supplying clean air into a face shield of the welding mask. According to an embodiment of the present invention, more specifically, the air supplying device comprises a housing connected to the face shield, a connection member connected to a supply port of the housing, a first opening/closing member connected to a first outlet part of the housing, and a second opening/closing member connected to a second outlet of the housing. Therefore, the air supplying device is capable of conveniently adjusting direction of a bellows hose connected to supply the air and also adjusting quantity and direction of the air being supplied.

Abstract: A respiratory mask having a shell and a cushion that is adhered to a user's face is sufficiently rigid to provide dimensional stability and a constant volume between the respiratory mask and the user's face, while also being comfortable and conformable to a user's individual facial features. The respiratory mask may cover the nose, the mouth, or both of the user and is useful for respiratory therapies including sleep apnea. The respiratory mask may have a quick release mechanism such as a pull tab that tears a portion of the mask when pulled to allow access to the user's breathing passage or a pull string embedded in the adhesive that breaks the seal between the adhesive and the user's face when pulled.

Abstract: An airway tube constricting device ASTD having a tubular constrictor attached to an oral piece and means for fastening the ASTD to the face of a patient provides for the correct placing and fixation of an airway tube within the patient's airways. A rotatable clamping means provides for constricting the airway tube thereby securing it to the oral piece. An optional mouthpiece attached to the proximal face of the oral piece provides for the protection of the tube from the jaws of a patient. One or two apertures in the oral piece provide for further insertion of tubing, auxiliary intubation tools and or probes.

Abstract: A respiratory mask assembly includes a frame and a forehead support secured to the frame. The forehead support includes a joining member secured to an upper portion of the frame and a cushion frame movably mounted to the joining member. One of the joining member and cushion frame includes a pair of shafts and the other of the joining member and cushion frame includes a pair of openings. The pair of shafts are respectively received in the pair of openings to couple the cushion frame to the joining member and enable the cushion frame to move relative to the joining member. Each of the shafts has a non-circular cross section defining a major longitudinal axis that is angled forwardly of a vertical axis of one of the joining member and cushion frame so as to angle toward a front portion of one the joining member and cushion frame.

Abstract: A respiratory protective hood design that aligns rigid components of the respiratory protective hood into a predetermined geometric configuration suitable for a visor to overlay without causing the visor to crease while in the packaged state. An exhalation unit abuts two filtration units on each side to create a substantially uniform surface area over which a visor is disposed while in a packaged state.

Abstract: A safety device is disclosed. The safety device includes a protective component wearable on a user's head. The safety device further includes a display unit configured to present status information at position in the periphery of the field of view of the user. The safety device includes a communications unit connectable to a wireless communication network and configured to send or receive status information. In certain embodiments, the safety device is a breathing apparatus or a head protection device. A method of presenting information to a user of the breathing apparatus is also disclosed.

Abstract: Apparel suitable for providing protection against noxious agents, wherein the apparel comprises a laminate material that provides a substantially effective barrier against the noxious agents. It is preferred that the laminate material comprises two or more layers, at least one of which is a barrier layer that is a substantially effective barrier against the noxious agents and at least one of which is a protective layer that protects the at least one barrier layer.

Abstract: A forehead pad that includes a base member having a first side adapted to be coupled to a forehead support member. The pad also includes a patient contacting member having a first side adapted to contact a surface of a patient. A neck portion couples a second side of the base member and a second side of the first patient contacting member. The neck portion includes at least one cutout to allow at least a portion of the first patient contacting member to move relative to the base member so that the patient contacting portion of the pad is self-aligning with the surface of the patient even if the base member is not parallel with the surface of the patient.

Abstract: A forehead support (10) is disclosed that is adapted to be secured to a respiratory mask (16). The forehead support (10) including a joining member (14) for securing to the mask (16) and a cushion frame (12) pivotally mounted to the joining member (14). The cushion frame (12) is adapted to locate one or more forehead cushions (25). The cushion frame (12) is also adapted to pivot relative to the joining member (14). The cushion frame (12) is also selectively lockable at two or more predetermined angular positions relative to the joining member (14). A respiratory mask assembly comprising a respiratory mask (16) and a forehead support (10) adapted to be secured to the mask (16) is also disclosed.

Abstract: A surgical garment includes a head gear apparatus for supporting a face shield and shroud. The head gear apparatus includes a helmet that supports a fan assembly, and that defines forward and rear ventilation passageways. The helmet includes a chin bar that defines a centrally located slot, and an upper ledge. The upper edge of the face shield contacts the upper ledge, while the lower edge of the shield includes a tab that extends through the slot. The chin bar and face shield include a plurality of magnetic elements that magnetically connect the lower edge of the face shield to the chin bar. The helmet is suspended from a strap assembly that is carried directly on the head of the wearer. The strap assembly includes an adjustable occipital support that bears against the occiput of the wearer. The face shield can include a plurality of film layers that can be removed when soiled.

Abstract: A helmet is particularly well suited for cold-weather use. The helmet includes a jaw shield that is detachable from a head portion. A breathing mask connects to the jaw shield via a mask adjustment mechanism that selectively axially moves the breathing mask toward and away from an inner surface of the jaw shield to precisely and accurately position the breathing mask against the nose and mouth of the helmet's wearer. A spring-loaded quick-release tinted shield is controlled by a lever that selectively raises and lowers the tinted shield. An eye shield pivotally connects to the helmet and is disposed in front of the tinted shield. An eye shield heating system on the eye shield electrically connects to the head portion of the helmet to provide electric power to the heating system.

Abstract: A respirator hood 1 that has an air chamber 6 arranged above the head of a user for delivery of breathable air. The air chamber 6 has an air inlet 13 connected to an air supply hose 5 and an air outlet 17 The outlet 17 is arranged to direct air away from the eyes of the user. The air chamber 6 forms an air duct 12 that substantially covers the top of the hood 1 above the user's head. The duct 12 is collapse-resistant so that the duct shape is maintained in use and air flow through the duct 12 is substantially unrestricted. As a result, a substantially uniform air flow can be achieved in use, which air flow pattern is repeatable from day to day and from hood to hood.

Abstract: An eye-wear article (93) for use with a respiratory mask (1) comprises a flat piece of transparent polymeric material providing a visor portion. The flat piece of polymeric material has shaped portions in a lower edge that fit over respective selected parts of the mask, and elongate tabs (95) that extend from each side and are inserted into respective guides (97) on the head harness (7, 8) of the mask to cause the flat piece of polymeric material to adopt a curved configuration and locate the visor portion in front of the eyes of the wearer. The tabs (95) can slide in the guides (97) to permit the eye-wear article to be moved out of engagement with the mask and onto the top of the wearer's while the mask is being worn, without disturbing the position of the mask on the wearer's face and without affecting the respiratory protection provided by the mask.

Abstract: The present invention provides a system for a gas delivery and monitoring system for delivering a gas product to a patient and receiving a gas product exhaled from a patient. In an embodiment, the gas delivery and monitoring system includes a head support made of resilient material and having therein a facial cavity. The facial cavity is configured to fit the contours of a patient's face and provides an oxygen rich environment for the patient while undergoing a medical procedure. In an embodiment, the facial cavity is shaped substantially in the form of a figure eight. In an embodiment, the facial cavity is further provided with one or more segmented edges that can be removed to further shape the facial cavity to the contours of the patient's face. In an embodiment, tubing is used to deliver oxygen from an oxygen source to the patient. Similarly, tubing is also used to receive carbon dioxide exhaled by the patient so that it might be measured by a carbon dioxide monitor.

Abstract: The present invention is directed to a respiratory helmet. The helmet is designed to provide protection to a user's cranium area. The helmet also has a visor designed to provide protection to the user's face area, an air intake system, and a parallel elliptical rail system. The visor can be positioned on the helmet, in front of the user's face area, and any position in between. The area between the visor, when the visor is positioned in front of the user's face area and the face area is called the breathing zone. The visor has at least two wheels, a top side and a bottom side wherein the bottom side is positioned closer to the user's chin when the visor is positioned in front of the user's face. The air intake system has an intake unit that receives a gaseous medium from a gaseous medium supply system or the ambient air into the helmet, and the intake unit directs the gaseous medium toward the breathing zone. The parallel elliptical rail system allows the visor to move in an elliptical motion.

Abstract: An escape hood, comprising a respirator, having an air filter suitable for filtering toxic air contaminants and positioning members to retain the respirator in a respiratory path of the user; an optical lens; a expanding member, permitting hood to expand from a compact storage configuration to a usage configuration; a sealing structure, around said air filter, for preserving said filter during storage; and an unsealing mechanism, adapted to allow a user to withdraw the escape hood from a storage vessel, wherein during withdrawal, said sealing structure is automatically unsealed. An escape hood system is also provided, comprising: an array of storage vessels, each vessel being adapted to receive a sealed escape hood; a retainer, for retaining a sealed escape hood within the vessel, wherein the escape hood is unsealed during withdrawal of the escape hood from a storage vessel; and an electronic sensor for determining an occupancy of a storage vessel.

Abstract: An adjustable forehead support for a nasal mask. The present invention discloses an adjustable forehead support for a nasal or full-face mask wherein the forehead support may be adjusted for the different shapes and sizes of a facial profile. The forehead support utilizes a dual-arm system which adjusts the position of the forehead support vis-à-vis the mask and/or air flow tube. The angle of the mask to the face may be adjusted with the present invention.

Abstract: Protective helmet device includes a helmet with a hard outer shell and a soft inner lining. In one embodiment, a tube inlet with multiple channels is coupled to the top of the outer shell, and is operative to allow the helmet to be connected to an air supply. In another embodiment, an insert on the inside of helmet contains multiple channels that are coupled to the tube inlet of the outer shell. Slots are contained in inner liner to allow air to flow from the air supply to the tube inlet, through the channels, and into the interior of the helmet. Air blows downward to keep carbon monoxide from coming up into the helmet, to keep air from blowing into the wearer's eyes, and to clear the shield.

Abstract: A modular helmet system having a helmet base to protect from impacts the crown of a wearer's head and terminating basally in a rear rim and side rims; a C-shaped extension detachably connected to said rims to protect from impacts, when fitted to the helmet base, the base of a wearer's skull; and a crown comb detachably connected centrally over the crown of the helmet base. The helmet base is provided with ventilation windows centrally located over its crown. The comb covers and seals said ventilation windows. The comb is also employed to secure the extension in place, when fitted on the helmet base.

Abstract: A helmet (12) includes a thermoelectric heat pump (14) mounted onto a rear surface of the helmet shell (12) for delivering temperature conditioned air to the interior of the helmet shell. A multi-layer structure (48) on the helmet shell interior distributes conditioned air across the scalp and directly onto the face. An optional scoop (38) directs ambient air to the heat pump (14). Another version locates the heat pump (68, 84) remotely and conditioned air is transmitted to the helmet apparatus (70, 78) via a flexible conduit (72, 85).

Abstract: A helmet is particularly well suited for cold-weather use. The helmet includes a jaw shield that is detachable from a head portion. A breathing mask connects to the jaw shield via a mask adjustment mechanism that selectively axially moves the breathing mask toward and away from an inner surface of the jaw shield to precisely and accurately position the breathing mask against the nose and mouth of the helmet's wearer. A spring-loaded quick-release tinted shield is controlled by a lever that selectively raises and lowers the tinted shield. An eye shield pivotally connects to the helmet and is disposed in front of the tinted shield. An eye shield heating system on the eye shield electrically connects to the head portion of the helmet to provide electric power to the heating system.

Abstract: A breathing mask is joined with a head fastening device that has at least one headstrap and at least one neckstrap. The headstrap and the neckstrap are connected with each other in the area of their extensions away from the breathing mask. The headstrap is fastened to the breathing mask at the top, and the neckstrap is fastened to the breathing mask at the sides in the orientation of the breathing mask when it is being worn. Regions of the neckstrap that are located next to the breathing mask are connected with one another by a chinstrap. The chinstrap extends essentially in the longitudinal direction of the neckstrap. End segments of the neckstrap, which are arranged between the breathing mask and the places at which the neckstrap is connected with the chinstrap, run towards the breathing mask at an angle of inclination relative to the chinstrap, so that they move farther and farther away from the chinstrap as they approach the breathing mask.

Abstract: Protective helmet comprising a two piece shell, an electric motor and impeller useful for creating a positive pressure environment in the head space, and a filter for removing particulates and other substances. The impeller introduces atmospheric air into an air channel defined by two detachably attached shell pieces. The air is pushed through a particulate filter in the air channel and then through at least one aperture into the head space. A heating element may be used to heat the air flow.

Abstract: A gas mask and breathing equipment is provided including a compressor. The gas mask and breathing equipment provides good flushing out of the carbon dioxide during the phase of expiration with the lowest possible compressor output. An air channel (31) is formed by the visor (5) and an inner wall (4) extending in parallel to the visor and is provided in the area of the visor (5). The air is discharged through gas discharge openings (6) at the inner wall (4).

Abstract: A modular respirator system has interchangeable facial lenses and body seals such as a full facepiece seal or a hood. A method of conversion from a full facepiece respirator to a hood respirator, or vice versa, is also disclosed. In one embodiment, lens conversion is accomplished without changing the type of body seal. In another embodiment, a breathable gas delivery conduit is connected to the facial lens and interchanged between the body seals together with the facial lens.

Abstract: A multi-phase headset (50) for aircraft crew members is provided which includes an inflatable gas mask unit (54) and a visor unit (56), supported on the head of a user (60) by mounting assembly (52). The overall headset (50) also has a selectively and/or automatically operable motive and control assembly (60). Preferably; the mounting assembly (52) includes a pair of ear pieces (62, 64) and a strap assembly (66) to allow positioning of the headset (50) on the user's head, with the mask and visor units (54, 56) adjacent the crown of the user's head. In the event of an emergency, the mask unit (54) is lowered and the mask body (124) is inflated for delivery of breathable gas to the user (60). Also, the visor unit (56) may be lowered to a use position atop mask unit (54). The pneumatically or electrically operated motive and control assembly (60) serves to move the mask and visor units (54, 56) between their retracted and deployed position.

Abstract: A helmet is particularly well suited for cold-weather use. The helmet includes a jaw shield that is detachable from a head portion. A breathing mask connects to the jaw shield via a mask adjustment mechanism that selectively axially moves the breathing mask toward and away from an inner surface of the jaw shield to precisely and accurately position the breathing mask against the nose and mouth of the helmet's wearer. A spring-loaded quick-release tinted shield is controlled by a lever that selectively raises and lowers the tinted shield. An eye shield pivotally connects to the helmet and is disposed in front of the tinted shield. An eye shield heating system on the eye shield electrically connects to the head portion of the helmet to provide electric power to the heating system.

Abstract: A safety helmet includes a hat having an arcuate, elongated recessed area defined in an inner face of the hat and a through hole defined through a periphery of the hat. A lining is detachably connected to the inner face of the hat so as to define an air duct inside the safety helmet.

Abstract: The present invention is directed to a respiratory helmet. The helmet is designed to provide protection to a user's cranium area. The helmet also has a visor designed to provide protection to the user's face area, an air intake system, and a parallel elliptical rail system. The visor can be positioned on the helmet, in front of the user's face area, and any position in between. The area between the visor, when the visor is positioned in front of the user's face area and the face area is called the breathing zone. The visor has at least two wheels, a top side and a bottom side wherein the bottom side is positioned closer to the user's chin when the visor is positioned in front of the user's face. The air intake system has an intake unit that receives a gaseous medium from a gaseous medium supply system or the ambient air into the helmet, and the intake unit directs the gaseous medium toward the breathing zone. The parallel elliptical rail system allows the visor to move in an elliptical motion.

Abstract: A helmet for artificial respiration without the aid of masks, comprising a containment body with at least one optically transparent portion, which can accommodate hermetically the head of a patient. The containment body has an air intake port that can be connected to a ventilation apparatus and an outlet port. The helmet further comprises, on the containment body, substantially at the mouth of the patient being treated, an opening that can be closed removably by a closure element.

Abstract: Protective helmet comprising a two piece shell, an electric motor and impeller useful for creating a positive pressure environment in the head space, and a filter for removing particulates and other substances. The impeller introduces atmospheric air into an air channel defined by two detachably attached shell pieces. The air is pushed through a particulate filter in the air channel and then through at least one aperture into the head space. A heating element may be used to heat the air flow.

Abstract: A gas mask has a facepiece defining an interior chamber and an opening spanning a front portion of facepiece. An optical panel visor is mounted in the opening in the front portion of the facepiece. A hinge joins opposite sides of the visor along a vertical line for relative rotational movement of the opposite sides of the optical panel and the facepiece with respect to each other.

Abstract: An eye-wear article (93) for use with a respiratory mask (1) comprises a flat piece of transparent polymeric material providing a visor portion. The flat piece of polymeric material has shaped portions in a lower edge that fit over respective selected parts of the mask, and elongate tabs (95) that extend from each side and are inserted into respective guides (97) on the head harness (7, 8) of the mask to cause the flat piece of polymeric material to adopt a curved configuration and locate the visor portion in front of the eyes of the wearer. The tabs (95) can slide in the guides (97) to permit the eye-wear article to be moved out of engagement with the mask and onto the top of the wearer's while the mask is being worn, without disturbing the position of the mask on the wearer's face and without affecting the respiratory protection provided by the mask.