Abstract: A filtering face mask 10 that has a mask body and a new exhalation valve 14. The mask body is adapted to fit at least over the nose and mouth of a person to help define an interior gas space when the mask is worn. The exhalation valve 14 permits fluid communication between the interior gas space and an exterior gas space. The exhalation valve 14 has a valve seat 20 and a flap 22. The valve seat 20 includes a resilient seal surface 24 and an orifice 30 through which exhaled air may pass to leave the interior gas space. The flap 22 is mounted to the valve seat 20 such that the flap 22 makes contact with the resilient seal surface 24 when the valve is in its closed position and such that the flap 22 can move away from the seal surface 24 in response to an exhalation to allow exhaled air to pass through the orifice 30 to ultimately enter the exterior gas space.

Abstract: In one embodiment, the invention provides a device for decreasing intracranial or intraocular pressures. The device comprises a housing having an inlet opening and an outlet opening that is adapted to be interfaced with a person's airway. The device further includes a valve system that is operable to regulate respiratory gas flows through the housing and into the person's lungs during spontaneous or artificial inspiration. The valve system assists in lowering intrathoracic pressures during each inspiration to repetitively lower pressures in the venous blood vessels that transport blood out of the head to thereby reduce intracranial or intraocular pressures.

Abstract: An anti-asphyxia valve includes at least one flap having a first portion adapted for mounting to the housing and a second portion adapted to flex between a first open position allowing gas to pass from the patient side to the housing interior through the at least one port, and from the blower side through the at least one port, to atmosphere when a difference in gas pressure in the housing interior and atmosphere is below a predetermined operating threshold, and a second forcibly closed position substantially occluding the at least one port when the difference in gas pressure between the housing interior and atmosphere is substantially equal to or above the operating threshold.

Abstract: The present invention provides a vent assembly suitable for use with a respiratory mask of the type used in CPAP treatment. In one embodiment the vent is made of a thin air permeable membrane. Generally, the membrane is thinner than 0.5 mm. The membrane can be made of a hydrophobic material such as polytetrafluoroethylene (PTFE). The membrane can also be fabricated from expanded PTFE. The expanded PTFE membrane is mounted on a polypropylene scrim. The pores of the membrane have a reference pore size of 10 to 15 microns. In an alternative embodiment, the vent assembly includes a vent constructed from stainless steel. In another embodiment the membrane has a superficial cross-sectional area of approximately 500 mm2. In another embodiment the vent assembly comprises a membrane attached to a vent frame, the vent assembly forming an insert which can be removably attached to a mask frame.

Abstract: A pressure support system having enhanced noise reduction and a valve assembly for use in pressure support system. The pressure support system includes a pressure generator having an inlet and an outlet. A first conduit defining a tortuous path is coupled between a gas source and the inlet of the pressure generator. A second conduit coupled to the outlet of the pressure generator delivers the flow of gas from the pressure generator to a patient. A valve assembly communicates gas from the second conduit to the first conduit to control the pressure or a rate of the flow of gas in the second conduit. By communicating gas from the second conduit to the first conduit, the noise associated with exhausting gas from the second conduit is muffled by the tortuous path of the first conduit.

Abstract: A filtering face mask that has a mask body and an exhalation valve. The mask body is adapted to fit over the nose and mouth of a wearer. The exhalation valve is attached to the mask body and has a valve seat that includes a seal surface and an orifice that is circumscribed by the seal surface. The valve also has a single flexible flap that has a fixed portion and a free portion and first and second opposing ends. The first end of the single flexible flap is associated with the fixed portion of the flap so as to remain at rest during an exhalation, and the second end is associated with the free portion of the flexible flap so as to be lifted away from the seal surface during an exhalation. The second end also is located below the first end when the filtering face mask is worn on a person. The flexible flap is positioned on the valve seat such that the flap is pressed towards the seal surface in an abutting relationship therewith when a fluid is not passing through the orifice.

Abstract: There is described a demand valve for a breathing apparatus with a “first breath” mechanism, wherein a demand valve is held closed by resiliently latching an operating diaphragm of the valve in a position wherein the valve is closed. The diaphragm is resiliently biased towards opening the valve, and the resilient latch is arranged to exert sufficient force so as not to be overcome by the resilient bias alone, but so as to be overcome by the combination of the resilient bias and a predetermined pressure difference across the diaphragm caused by sub-ambient pressure within the facepiece of the breathing apparatus.

Abstract: An anti-asphyxia valve is adapted to, in use, be disposed between a patient and structure to deliver a breathable gas to the patient. The valve includes a housing having an interior, at least one port to provide fluid communication between the housing interior and atmosphere and at least one flap including a first portion and a second portion. The first portion is adapted for mounting to the housing. The second portion is adapted to flex between a first biased open position allowing gas to pass from the housing interior through the at least one port to atmosphere when a difference in gas pressure in the housing interior and atmosphere is below a predetermined operating threshold and a second forced closed position substantially occluding the at least one port when the difference in gas pressure between the housing interior and atmosphere is substantially equal to or above the operating threshold.

Abstract: A method for making a filtering face mask that comprises providing a fluid-permeable multi-layered mask body comprising a structural supporting layer and a filtration layer, the multi-layered mask body being configured to fit over the nose and mouth of a person and having an aperture disposed therein; providing an exhalation valve comprising a base portion and a deformable hollow plastic extension member that extends from the base portion to a tip; inserting the tip through the aperture; and deforming the extension member so as to make an effective seal between the exhalation valve and the mask body.

Abstract: A filtering face mask that includes a mask body and an exhalation valve. The mask body is adapted to fit at least over the nose and mouth of a wearer to create an interior gas space when worn, and the exhalation valve is in fluid communication with the interior gas space. The exhalation valve comprises a valve seat that has a seal surface and an orifice through which an exhale flow stream may pass to leave the interior gas space. A flexible flap is mounted to the valve seat such that the flap makes contact with the seal surface when the valve is in its closed position and such that the flap can flex away from the seal surface during an exhalation to allow exhaled air to pass through the orifice to ultimately enter an exterior gas space. The flexible flap has at least first and second juxtaposed layers where at least one of the layers is stiffer or has a different elastic modulus than the other layer.

Abstract: A personal air filtration device has a cylindrical exhalation tube, with a one-way valve thereon. Concentric around the periphery of the exhalation tube and integrally connected to the exhalation tube rearward (proximate the user's mouth) of the one-way valve is a filter media housing. Filter media is contained between the housing and the tube. A plurality of perforations in the exhalation tube, rearward of the one way valve but forward from the housing connection ring, provide inhaled air ingress to the exhalation tube. Inhaled air forces the one-way valve closed, so that air is directed through the filter media, passes through the perforations and into the exhalation tube where the user can take in the cleansed air. The pressure of the exhaled air through the exhalation tube causes the one-way valve to open, so that exertion by the user is minimized.

Abstract: A mask for use in inhaling a substance includes a mask housing defining a chamber. The housing has an inlet and an outlet communicating with the chamber. A valve is disposed in the inlet and is integrally formed with the housing, such that the valve and the housing are formed as a one-piece unit. In a preferred embodiment, the housing further comprises an exhaust port and an exhalation valve disposed in the exhaust port, with a shield disposed around the exhaust port. In another aspect, a method of manufacturing a mask also is provided.

Abstract: Exhalation and inhalation valves that are sized and adapted to fit on a mask body of a personal respiratory protection device. The exhalation and inhalation valves comprise a valve seat that has a seal surface and an orifice through which an exhale flow stream may pass to leave the interior gas space. A flexible flap is mounted to the valve seat such that the flap makes contact with the seal surface when the valve is in its closed position and such that the flap can flex away from the seal surface during an exhalation to allow exhaled air to pass through the orifice to ultimately enter an exterior gas space. The flexible flap has at least first and second juxtaposed layers where at least one of the layers is stiffer or has a different elastic modulus than the other layer. These valves provide extraordinarily lower pressure drop in use, and they operate more efficiently and require less actuation power to operate.

Abstract: A component is attached to filtration material by providing the component with a deformable extension member that is preferably integral with the component and that extends from a base portion of the component. The extension member is inserted through an opening provided through the filtration material and is then deformed to provide a mechanical clamp that is utilized in attaching the component in position. In certain embodiments, the component is an attachment such as an exhalation valve of a respiratory mask.

Abstract: A system is disclosed comprising a high pressure gases source: for example a compressor, a low cross section conduit adapted to convey gases from the compressor, and a patient interface delivering gases to the patient. The patient interface includes valve member which is substantially closed during inspiration and venting externally during expiration. The combination of the low cross section and lightweight conduit and the valve member result in increased patient comfort.

Abstract: A medication inhalation therapy apparatus designed for the delivery of finely misted medicines to a patient in conjunction with the inhalation of 100% oxygen by the patient. The apparatus comprises a facemask equipped with an oxygen port for delivering oxygen, the facemask placed about or on the face of the patient. The facemask has a nebulizer mechanism disposed thereon, which is used to deliver medication in addition to oxygen. The nebulizer mechanism comprises a nebulizer port, which rotates 90 degrees in either direction to allow the present invention to be used in various angles. The nebulizer port is adapted to receive a nebulizer head, wherein are placed inhaleable medications, which are nebulized. When the apparatus is used for medication inhalation therapy, the nebulizer head receives oxygen for nebulizing inhaleable medications placed therein, the oxygen received from an oxygen port, which delivers oxygen to the facemask.

Abstract: Filtering face mask 10 has a mask body 12 and an exhalation valve 14. The mask body 12 is adapted to fit over the nose and mouth of a person, and the exhalation valve 14 is attached to the mask body 12. The exhalation valve 14 has a valve seat 26 and a single flexible flap 24. The valve seat 26 includes a seal surface 31 and an orifice 32. The orifice 32 is circumscribed by the seal surface 31. The single flexible flap 24 has a fixed portion 28 and one free portion 38. The one free portion 38 has a free end, and the fixed portion 28 is located off-center of the flexible flap 24 away from the free end and is secured to the valve seat 26 outside the orifice 32. The one free portion 38 is pressed toward the seal surface 31 when the wearer is neither inhaling or exhaling. The free portion 38 can be lifted from the seal surface 31 during an exhalation.

Abstract: An exhaust port assembly comprising a conduit carries a flow of gas. A vent assembly having a fixed exhaust area is provided on the conduit for venting a flow of exhaust gas from within the conduit to ambient atmosphere. The vent assembly is configured so as to minimize noise associated with the flow of exhaust gas passing to atmosphere, diffuse the flow of exhaust gas passing to ambient atmosphere over a relatively large area, and minimize the area occupied by the venting assembly on the conduit.

Abstract: A vent assembly for use with a respiratory mask of the type used in CPAP treatment includes a porous disk portion that is attached to a biasing member such that the disk portion is maintained in a substantially sealed position against a main vent to minimize airflow through at least one side vent of the vent assembly. Debris build-up on the disk portion can cause the biasing member to deflect to provide an additional path for airflow through the at least one side vent. In another embodiment, the vent assembly can also include an anti-asphyxia feature to provide an airflow path from the environment to the user. An oxygen diverter valve may be disposed between the breathing apparatus flow generator and an oxygen injection port.

Abstract: The present invention provides a vent assembly suitable for use with a respiratory mask of the type used in CPAP treatment. In one embodiment the vent is made of a thin air permeable membrane. Generally, the membrane is thinner than 0.5 mm. The membrane can be made of a hydrophobic material such as polytetrafluoroethylene (PTFE). The membrane can also be fabricated from expanded PTFE. The expanded PTFE membrane is mounted on a polypropylene scrim. The pores of the membrane have a reference pore size of 10 to 15 microns. In an alternative embodiment, the vent assembly includes a vent constructed from stainless steel. In another embodiment the membrane has a superficial cross-sectional area of approximately 500 mm2. In another embodiment the vent assembly comprises a membrane attached to a vent frame, the vent assembly forming an insert which can be removeably attached to a mask fame.

Abstract: An inhalation opening 6 and an exhalation-opening 4 are formed in the facepiece 2 of a breathing apparatus 1 and the openings can be closed with an inhalation valve 8 and exhalation valve 7, respectively. If a person wearing the breathing apparatus 1 inhales, the inhalation valve 8 is open and the exhalation valve 7 is closed. A photointerrupter 11 senses the closing operation of the exhalation valve 7 and supplies electric power to a motor 9 to drive a blower 16.

Abstract: A valve for use in continuous positive airway pressure (CPAP) devices includes a valve body that is disposed at or between the patient mask and the source of positive airway pressure. The valve body includes first and second exhaust paths for exhausting gas from the mask. A floating valve seat is disposed in the valve body and is moveable between first and second positions. A moveable spring-biased piston is releasably engaged with the floating valve seat. When the floating valve seat is in the first position, the moveable spring-biased piston is disengaged from the valve seat and gas travels out the first exhaust flowpath. When the floating valve seat is in the second position, the moveable spring-biased piston is engaged with the valve seat and gas travels out the second exhaust flowpath. The valve provides substantially constant positive airway pressure to the patient at pressures above the threshold pressure level of the valve.

Abstract: A device for reducing dead space in a ventilator system has a first tube connectable to the dead space in the ventilator system for producing a flow path for the transport of gas from dead space in the ventilator system, a suction device connected to the first tube for generating an adjustable negative pressure in the first tube, a second tube connectable to dead space in the ventilator system, for producing a flow path for the transport of gas to dead space in the ventilator system, a pump connected to the second tube for generating an adjustable positive pressure in the second tube, and a control unit which regulates the suction device and the pump. The suction device and the pump are formed by a first chamber and a second chamber, respectively, in an enclosure, separated by a gas-tight, moving partition. The control unit regulates the moving partition to regulate the suction device and the pump for achieving simpler and more reliable operation.

Abstract: An elbow assembly for use in a respiratory mask, which includes an elbow, an inlet port, an exhaust port, and a baffle separating the inlet port from the exhaust port. A mask assembly includes a cushion comprising at least one gusset and an aperture for connection to the elbow assembly.

Abstract: A flow regulation vent (10) for regulating flow from a pressurized gas supply includes a fixed portion (14) adapted to engage a gas supply conduit and a spring force biased movable portion (12) connected by a hinge (16) to the fixed portion and flowingly connected to the pressurized gas supply. The fixed portion includes a gas flow orifice (20). The movable portion is pivotally movable between 1) a relaxed position, whereby at a specified minimum operating pressure, the movable portion is pivoted by the spring force away from the fixed portion to a position to establish a first gas flow area between the movable portion and the gas flow orifice; and 2) a fully pressurized position, whereby at a specified maximum operating pressure, the pressurized gas offsets the spring force to pivot the movable portion to a position adjacent the fixed portion to establish a minimum gas flow area between the movable portion and the gas flow orifice.

Abstract: A pressure regulator suitable for use as a breathing demand valve in self-contained breathing equipment comprising a first chamber incorporating an inlet port having an inlet valve therein, preferably in the form of a poppet valve and biased so as to seal of the inlet port, and separated from a second chamber by a diaphragm. The diaphragm co-operates with the end of a stem extending from the poppet valve member of the inlet valve such that, upon inhalation by the user, the diaphragm is deflected towards the inlet valve and exerts a force on the poppet valve stem sufficient to open the poppet valve and, upon exhalation by the user, the diaphragm is deflected away form the inlet valve so that the diaphragm no longer contacts the end of the poppet valve stem and the inlet valve closes.

Abstract: In accordance with the present invention an anesthesia delivery device is disclosed for use on a patient having a mouth and a nose having a naris. The delivery device is capable of being coupled to a ventilation system having an inspiratory gas input for delivering gas to the patient and an exhaust gas output for delivering gas from a patient to the ventilation system. The anesthesia device includes an inspiratory gas line having a machine end and a patient end. The machine end is capable of being fluidly coupled to the inspiratory gas input of the ventilation system, and the patient end is configured for being received within the naris of the patient for delivering inspiratory gas to the naris of the patient. The device also includes a face mask having a dome portion sized to cover the patient's nose without covering the patient's mouth. The dome portion defines an inside air space between the patient's nose and the dome portion, and an outside air space exterior of the dome portion.

Abstract: A respiratory monitor apparatus comprises, in combination, a flexible mask fabricated from a stretchable fabric, such as spandex, that is designed to support a pneumotach flow measuring instrument in a way that does not require the instrument to be placed in the wearer's mouth, yet still remaining in fluid communication with the wearer's mouth and with little or no dead-space or leakage between the mask member and the wearer's face.

Abstract: An improved therapy for both clearing the blood of unwanted carbon monoxide and anaesthetic chemicals and for rapidly re-oxygenating blood suffering from carbon monoxide poisoning or smoke inhalation. It also includes a therapy delivery device for carbon dioxide and oxygen metering and mixing apparatus for gases under pressure particularly for respirators and medical devices which has a plurality of compressed gas supply lines which are connected to a mixing device for delivery into a demand regulator (respirator or face mask). It includes a gas selection device, an automatic shut off of the carbon dioxide, a purging system, metering of the gases and a mixing chamber to promote a homogeneous mixture of gases and sized for field use by emergency care operators. The therapy is a mixture of carbon dioxide and oxygen for promoting the rapid oxygenation of the patient's blood supply for cases of carbon monoxide poisoning, smoke inhalation or other cases where the blood oxygen level is low.

Abstract: A method and device for effective delivery of a gas such as oxygen for inhalation is provided by sequentially diluting room air to the flow of gas during a respiratory cycle. A mask assembly is described that comprises an inspiratory and expiratory limb each containing a very low resistance one-way valve, and a sequential dilution conduit (leading from the atmosphere to the inspiratory limb) with a one-way valve that has a slightly positive cracking pressure. A gas reservoir is also attached to the inspiratory limb. During expiration, the reservoir is filled with oxygen, for example, flowing from the oxygen source. During inspiration, oxygen from the oxygen source and the reservoir are drawn preferentially. If the oxygen flow is equal to or greater than the minute ventilation of the subject, no atmospheric air is entrained into the mask assembly and the subject gets pure oxygen. If the minute ventilation (tidal volume) exceeds the oxygen flow, the reservoir is depleted.

Abstract: An apparatus meant for human use to supplement breathing while at high altitude in aircraft for emergency use. The apparatus includes a valve as an actuator to discharge oxygen into an attached facemask. A small cylinder containing oxygen under pressure is inserted and attached to the valve. Once assembled, the invention is stored in aircraft to be available for instant use. If a cabin depressurization emergency should occur, an occupant may access oxygen immediately by pressing a valve lever to start the flow of oxygen. By adjusting a knob located on the valve lever the user may control the flow of oxygen and extend oxygen use to allow time for evasive action.

Abstract: A valve for use in continuous positive airway pressure (CPAP) devices includes a valve body that is disposed at or between the patient mask and the source of positive airway pressure. The valve body includes first and second exhaust paths for exhausting gas from the mask. A floating valve seat is disposed in the valve body and is moveable between first and second positions. A moveable spring-biased piston is releasably engaged with the floating valve seat. When the floating valve seat is in the first position, the moveable spring-biased piston is disengaged from the valve seat and gas travels out the first exhaust flowpath. When the floating valve seat is in the second position, the moveable spring-biased piston is engaged with the valve seat and gas travels out the second exhaust flowpath. The valve provides substantially constant positive airway pressure to the patient at pressures above the threshold pressure level of the valve.

Abstract: A connector includes a mask end for connecting with the interior of a respiratory mask, a supply conduit end, and a gas washout vent passage having an inlet adjacent to, or forming part of, the mask end in fluid communication with the interior of the respiratory mask and an outlet in fluid communication with atmosphere. The vent outlet of the vent passage is disposed on the side of the connector remote from the mask end. A respiratory mask includes a mask shell, a mask inlet for connecting with the outlet of a breathable gas supply conduit, and a gas washout vent passage. A vent outlet is disposed on the side of the mask remote from the mask interior and is adapted to direct the washout gas in a direction substantially parallel to the longitudinal axis of the mask inlet and away from the mask inlet.

Abstract: A low noise exhalation port for a respiratory mask has a body including a proximal end operably connected to an internal area of the mask to vent carbon dioxide exhaled by a person from the mask, and a distal end. The venting device vents a gas out of the respiratory mask so as to substantially reduce inhalation by the person of the exhaled carbon dioxide. An exit passage portion is provided at the distal end and extends partially through the body and communicates with an exterior of the mask, the exit passage portion having a substantially regular cross-sectional area. An entrance passage portion is provided at the proximal end and extends partially through the body, the entrance passage portion communicating with an interior of the mask and further communicating with the exit passage portion, the entrance passage portion decreasing in cross-sectional area from the interior of the mask to the exit passage portion.

Abstract: A respiratory mask having a variable flow venting is provided according to the invention, including a gas supply hose, a mask shell adapted to output a gas to a respiratory system of a person, the mask shell adapted to be connected to the gas supply hose, and an exhaust gas flow volume regulating device which maintains a substantially constant gas flow volume out of the respiratory mask independent of an internal gas pressure inside the respiratory mask.

Abstract: A facial mask comprises a mask body that is adapted to be coupled to a patient's face. A valve system is coupled to the mask body to permit the inflow of respiratory gasses into the mask body and to permit the outflow of respiratory gasses from the mask body. A metronome is coupled to the mask body to produce a repeating chest compression signal to facilitate the performance of regular chest compressions when performing cardio pulmonary resuscitation. The metronome may also produce a ventilation signal to facilitate the proper ventilation of the patient.

Abstract: The present invention provides a vent assembly suitable for use with a respiratory mask of the type used in CPAP treatment. In one embodiment the vent is made of a thin air permeable membrane. Generally, the membrane is thinner than 0.5 mm. The membrane can be made of a hydrophobic material such as polytetrafluoroethylene (PTFE). The membrane can also be fabricated from expanded PTFE. The expanded PTFE membrane is mounted on a polypropylene scrim. The pores of the membrane have a reference pore size of 10 to 15 microns. In an alternative embodiment, the vent assembly includes a vent constructed from stainless steel. In another embodiment the membrane has a superficial cross-sectional area of approximately 500 mm2. In another embodiment the vent assembly comprises a membrane attached to a vent frame, the vent assembly forming an insert which can be removeably attached to a mask fame.

Abstract: A component is attached to filtration material by providing the component with a deformable extension member that is preferably integral with the component and that extends from a base portion of the component. The extension member is inserted through an opening provided through the filtration material and is then deformed to provide a mechanical clamp that is utilized in attaching the component in position. In certain embodiments, the component is an attachment such as an exhalation valve of a respiratory mask.

Abstract: A nasal or full-face mask and headgear system for improving pediatric compliance of ventilation therapy, including CPAP or BiPAP, and sized for pediatric use is provided. Each mask has a shallow concave rigid shell bearing the visage of a caricature. Unique caricatures are predetermined to represent different sizes of masks. Further, headgear is provided in keeping with the caricature theme and having additional aspects such as ears, removably attached to it. Each mask has an inner inflatable cuff to improve fit and an outer replaceable cuff to facilitate cleaning as well as fitting. The headgear is attached to the mask at three contact points using straps having key slots attached to ends of the straps and raised buttons on the mask shell. The straps are adjustable for length using Velcro™ and are not adjusted each time the system is placed onto the patient, improving positioning of the mask when the patient is asleep or resistant.

Abstract: A filtering face mask that covers at least the nose and mouth of a wearer and that includes an exhalation valve. The exhalation valve opens in response to increased pressure when the wearer exhales to allow the exhaled air to be rapidly purged from the mask interior. An exhale filter element is placed in one of several locations in the exhale flow stream to remove contaminants from the exhaled air. The face mask is beneficial in that it provides comfort to the wearer by allowing warm, moist, high-CO2-content air to be rapidly evacuated from the mask interior through the valve and also protects the wearer from splash fluids and polluted air while at the same time protecting other persons or things from being exposed to contaminants in the exhale flow stream.

Abstract: A combined patient interface and integrated exhaust assembly that passes a controlled flow of gas from an interior of a patient interface to ambient atmosphere at a predetermined flow rate irrespective of variations of pressure in the interior of the patient interface device relative to ambient atmosphere. Control of the flow of exhaust gas is achieved by varying the effective cross sectional area of the exhaust path communicating the interior of the patient interface with ambient atmosphere based on the pressure in the interior of the patient interface relative to ambient atmospheric pressure.

Abstract: A nasal mask has a shell portion that is a hollow enclosure with a rearwardly facing opening that is defined by edge portions of the shell portion. A resiliently deformable endless interface member engages and extends around the edge portion of the opening and forms a seal between the shell portion and the user's face. The shell portion and the interface member are generally symmetrical about a median place. The shell portion has two gas inlet orifices, one on each side of the median place. The shell portion has a tubular exhalation outlet extending from the face of the mask. The mask is further provided with a balloon exhalation valve connected to the exhalation outlet for alternately venting and sealing the interior of the mask during exhalation and inhalation, respectively.

Abstract: The present invention provides a vent assembly suitable for use with a respiratory mask of the type used in CPAP treatment. In one embodiment the vent is made of a thin air permeable membrane. Generally, the membrane is thinner than 0.5 mm. The membrane can be made of a hydrophobic material such as polytetrafluoroethylene (PTFE). The membrane can also be fabricated from expanded PTFE. The expanded PTFE membrane is mounted on a polypropylene scrim. The pores of the membrane have a reference pore size of 10 to 15 microns. In an alternative embodiment, the vent assembly includes a vent constructed from stainless steel. In another embodiment the membrane has a superficial cross-sectional area of approximately 500 mm2. In another embodiment the vent assembly comprises a membrane attached to a vent frame, the vent assembly forming an insert which can be removeably attached to a mask fame.

Abstract: A mask (10) for use with a system for supplying breathable gas pressurised above atmospheric pressure to a human or animal's airways. The mask (10) includes a mask shell (12) which is, in use, in fluid communication with a gas supply conduit and a gas washout vent assembly (20). The gas washout vent assembly (20) includes at least one gas washout orifice (22) extending from a first side of the vent assembly (20) positioned, in use, adjacent the human or animal's face and a second side positioned, in use, adjacent the atmosphere. The cross-sectional area of the orifice (22) at the first side is larger than the cross-sectional area of the orifice (22) at the second side.

Abstract: A mask (10) for use with a system for supplying breathable gas pressurised above atmospheric pressure to a human or animal's airways. The mask (10) includes a mask shell (12) which is, in use, in fluid communication with a gas supply conduit (30), and a gas washout vent assembly (20). At least the region of the mask shell (12) or conduit (30) surrounding or adjacent the vent assembly is formed from a relatively flexible elastomeric material.

Abstract: An exhalation valve 14 for a filtering face mask 10 has a flexible flap 24 that makes contact with a curved seal ridge 30 of a valve seat 26 when the valve 14 is in the closed position. The curvature of the seal ridge 30 corresponds to a deformation curve exhibited by the flexible flap 24 when secured as a cantilever at one end and exposed at its free portion to a uniform force and/or a force of at least the weight of the free portion of the flexible flap. A seal ridge curvature corresponding to a flexible flap exposed to uniform force allows the flexible flap 24 to exert a generally uniform pressure on the seal ridge to provide a good seal. A ridge curvature corresponding to a flexible flap exposed to a force of at least the weight of the flap's free portion allows the flexible flap 24 to be held in an abutting relationship to the seal ridge 30 under any static orientation by a minimum amount of force, thereby providing a face mask 10 with an extraordinary low pressure drop during an exhalation.

Abstract: An improved crew oxygen mask and stowage assembly combination (10) is provided including a stowage box (12) equipped with a door (22), with a crew mask assembly (14) made up of a mask (48), gas-conveying tubing (50) and valve unit (46). The box (12) also includes a valve-controlling switch lever (44) for selective gas-on or gas-off operation of valve unit (46). In normal conditions, the mask (48) and tubing (50) are stowed within box (12) with lever (44) oriented in the gas-on position, so that the tubing (50) is pressurized and mask (48) may be quickly pulled from the box (12) and used. After such use, the switch lever (44) is shifted to the gas-off position, causing the tubing (50) to be depressurized; this allows easy restowage of the tubing (50) and mask (48) within the box (12). However, when door (22) is closed, the switch lever (44) is cammed back to the gas-on position, thereby repressurizing tubing (50) and returning the combination (10) to a full-ready condition.

Abstract: The invention describes an inhalation or breathing mask for therapeutic nebulisers, in which around a connecting socket 4 for the therapeutic nebuliser is arranged an exhalation valve consisting of exhalation openings and a flexible valve element. The exhalation openings 7 are formed by exhalation channels 8 and can be closed individually by closure devices, for example stoppers, in order to set a predefined exhalation resistance.

Abstract: The inhalation atomizer of the invention has a valve box, which is divided into two sub-chambers by a partition wall. The valve box is closed by a valve box cover. A one-piece valve element projects into both sub-chambers and closes the openings provided in the sub-chambers and in the valve box cover in dependence on the breathing of the patient.

Abstract: A respiratory monitor apparatus comprises, in combination, a flexible mask fabricated from a stretchable fabric, such as spandex, that is designed to support a pneumotach flow measuring instrument in a way that does not require the instrument to be placed in the wearer's mouth, yet still remaining in fluid communication with the wearer's mouth and with little or no dead-space or leakage between the mask member and the wearer's face.