The present invention is a compact and portable personal ultraviolet air irradiation system having an ultraviolet air irradiation unit, a breathing tube, and a face mask. Unfiltered air passes through the ultraviolet air irradiation unit and is purified to ensure biological material has been neutralized by utilizing UV LEDs in the germicidal wavelengths of 100-280 nm. The ultraviolet air irradiation unit may further purify air of air particulates, gases, vapors, and biological material by utilizing a HEPA filter. The ultraviolet air irradiation unit may provide variable pressure to the mask to meet the breathing demands of the user. Flow through the ultraviolet irradiation unit may be reversible to irradiate the exhalations of a user who may be infected with a virus or other disease spread through exhalations.

The present invention is a compact and portable personal ultraviolet air irradiation system having an ultraviolet air irradiation unit, a breathing tube, and a face mask. Unfiltered air passes through the ultraviolet air irradiation unit and is purified to ensure biological material has been neutralized by utilizing UV LEDs in the germicidal wavelengths of 100-280 nm. The ultraviolet air irradiation unit may further purify air of air particulates, gases, vapors, and biological material by utilizing a HEPA filter. The ultraviolet air irradiation unit may provide variable pressure to the mask to meet the breathing demands of the user. Flow through the ultraviolet irradiation unit may be reversible to irradiate the exhalations of a user who may be infected with a virus or other disease spread through exhalations.

A wearable respiratory isolation system is configured as an open collar to be worn loosely around the neck of the user, with an articulating arm positioning a mouthpiece in front of the mouth and nasal region of the user. The system provides filtered and sterilized air through a inhalation vent on the mouthpiece which creates a curtain of sterilized air in front of the users face, which protects the users face from air bourne pathogens provides sterile air for the user to inhale. Exhaled air is extracted through an exhalation vent on the mouthpiece, is decontaminated and exhausted to the rear of the user. A modified, background oriented Schlieren imaging technique is used to determine whether the user is inhaling or exhaling, and this information is used to control the flow of sterilized air and the capture of exhaled gases.

A personal protected-air system includes first and second rings, and a sleeve coupled on each end thereof to one of the rings. The first ring includes a port for receiving filtered air under pressure, a manifold in fluid communication with the port, and vents in fluid communication with the manifold and the interior region of the sleeve. The sleeve includes a transparent region. In use, the second ring fits over a user's head, the sleeve encases the user's head, and the first ring rests on a top portion of the user's head. The second ring includes an air passage providing fluid communication between an ambient environment and the interior region of the sleeve.

A personal protected-air system includes first and second rings, and a sleeve coupled on each end thereof to one of the rings. The first ring includes a port for receiving filtered air under pressure, a manifold in fluid communication with the port, and vents in fluid communication with the manifold and the interior region of the sleeve. The sleeve includes a transparent region. In use, the second ring fits over a user's head, the sleeve encases the user's head, and the first ring rests on a top portion of the user's head. The second ring includes an air passage providing fluid communication between an ambient environment and the interior region of the sleeve.

A cartridge holder for a respirator, the cartridge holder including a fit-check device with a sealing platen that can be actuated between a first, unsealed position and a second, sealed position in which at least a portion of the sealing platen contacts a major surface of a disposable filter cartridge within the cartridge holder so as to prevent airflow through the disposable filter cartridge.

A face mask includes a valve protector between a strap and an exhalation valve thereof. The valve protector's thickness defines a spacing between the strap and a strap retainer that is positioned on a mask body, disposed over the exhalation valve, and receives the strap. This spacing controls an extent of friction between the strap and the strap retainer.

A face mask includes a valve protector between a strap and an exhalation valve thereof. The valve protector's thickness defines a spacing between the strap and a strap retainer that is positioned on a mask body, disposed over the exhalation valve, and receives the strap. This spacing controls an extent of friction between the strap and the strap retainer.

A pulse modulated oxygen dispensing and pressurization system provides a variable range of controlled oxygen bolus to an enclosed breathing environment supporting and maintaining required pressure conditions in accordance with desired flow demand. As oxygen is consumed by the user from within the enclosed breathing environment, the exhaled gases and moisture are conditioned or vented to acceptable levels by additional systems associated with the environment. These additional systems cause an ongoing need to replenish the oxygen within the environment and maintain the required partial pressure of oxygen. Specific to one of a plurality of modes of operation, the system responds to changes in regulated output pressure by delivering a precisely metered periodic bolus volume of oxygen to support a requirement of the environment volume. The bolus is variable based on a plurality of factors to increase and decrease changes in rates of flow required to maintain regulated pressure.

A personal breathing system incorporating a phased-dilution demand oxygen regulator (PDDOR) is disclosed. In embodiments, the breathing system includes a pressurized oxygen source and oronasal mask, a dilution valve for supplying ambient air and a demand valve for supplying pure oxygen. The PDDOR senses the mask pressure associated with the start of an inhalation cycle, maintaining pressure to the demand valve through an initial demand phase during which 100% pure oxygen is supplied through the demand valve. Control pressure within the PDDOR drops throughout the initial demand phase; when the pressure drops below a lower threshold the PDDOR main valve is closed, blocking the demand valve and cutting off the oxygen supply. Ambient air is provided to the mask via a dilution valve to preserve flow to the user.