A pressure regulator assembly for an SCBA includes a valve assembly having a piston, a cylinder for receiving the piston, a sealing member for engagement by the piston, a conduit extending through the piston and facilitating fluid communication between an inlet chamber and a cavity of the cylinder, and a driving assembly for facilitating the engagement and disengagement of the piston responsive to a change of pressure in the outlet chamber. A bypass assembly for an SCBA is also disclosed.

A breathing apparatus includes a tank containing pressurized breathing gas, a regulator having an inlet connected to the tank, an outlet for providing breathing gas to a user, and a valve configured for controlling a flow of breathing gas between the inlet and the outlet. A facepiece includes a first port for connecting with the outlet of the regulator, a second port adapted to be connected to an air purifying system, and an exhalation valve. A pneumatic pressure adjustment assembly is in operative connection with the exhalation valve, and has a first pneumatic connection in operative connection with a second pneumatic connection in the regulator. The pneumatic pressure adjustment assembly is operable to adjust the internal facepiece pressure for opening the exhalation valve based on whether breathing gas is delivered to the pneumatic pressure adjustment assembly. An alignment mechanism is provided for aligning the regulator with the facepiece.

A demand regulator for a breathing apparatus. The demand regulator comprises: a flow regulation mechanism for regulating a flow of breathing gas, the flow regulation mechanism having a closed configuration in which breathing gas flow is substantially prevented; a connection mechanism for releasably connecting the flow regulator to a breathing mask, the connection mechanism comprising a release actuator for releasing the connection mechanism; a latch configured to be activated to thereby releasably retain the flow regulation mechanism in the closed configuration; a first latch activation mechanism configured for manual actuation by a user to thereby activate the latch; and a second latch activation mechanism configured to be actuated by the release actuator of the connection mechanism to thereby activate the latch during release of the connection mechanism.

A demand regulator for a breathing apparatus. The demand regulator comprises: a flow regulation mechanism for regulating a flow of breathing gas, the flow regulation mechanism having a closed configuration in which breathing gas flow is substantially prevented; a connection mechanism for releasably connecting the flow regulator to a breathing mask, the connection mechanism comprising a release actuator for releasing the connection mechanism; a latch configured to be activated to thereby releasably retain the flow regulation mechanism in the closed configuration; a first latch activation mechanism configured for manual actuation by a user to thereby activate the latch; and a second latch activation mechanism configured to be actuated by the release actuator of the connection mechanism to thereby activate the latch during release of the connection mechanism.

Disclosed herein are connection apparatus for connecting breathing gas delivery components of a breathing apparatus. The connection apparatus comprises a male connector configured to be received in a corresponding female port, the male connector comprising a perimeter wall defining an external shape of the male connector. In some examples, the male connector defines an insertion axis along which the male connector is receivable into a corresponding female port, and a distal edge of the perimeter wall defines a distal face of the perimeter wall and at least a portion of the distal face is inclined with respect to the insertion axis of the male connector. In some examples, the perimeter wall comprises first and second wall portions which taper together such that a first edge of the first wall portion and a first edge of the second wall portion are connected at an apex portion.

Disclosed herein are connection apparatus for connecting breathing gas delivery components of a breathing apparatus. The connection apparatus comprises a male connector configured to be received in a corresponding female port, the male connector comprising a perimeter wall defining an external shape of the male connector. In some examples, the male connector defines an insertion axis along which the male connector is receivable into a corresponding female port, and a distal edge of the perimeter wall defines a distal face of the perimeter wall and at least a portion of the distal face is inclined with respect to the insertion axis of the male connector. In some examples, the perimeter wall comprises first and second wall portions which taper together such that a first edge of the first wall portion and a first edge of the second wall portion are connected at an apex portion.

Unlike the existing powered air-purifying respirators (PAPR) that are bulky, heavy, and expensive the invention offers a light-weighted inexpensive portable PAPR consisted of a single piece secured on user's head. The respirator is for use in contaminated environment including one with highly contagious viruses such as SARS-CoV-2 that causes COVID-19. A clear visor of the respirator protects eyes, nose, and mouth. The rest of the user's head protected with a soft airtight cover. A small fan or fans pump air through the filters. Because the fan capacity exceeds airflow required for breathing, air pressure under the cover is slightly higher than ambient pressure. It protects the visor and user glasses from fogging and prevents leaks through any looseness. A special port allows use of equipment and devices as a stethoscope for medics or oxygen supply for patients. Despite the respirator primarily targeted for medical personnel and patients, its convenience, l lightness and affordability allow usage by general population especially at the time of an epidemic or a pandemic.

An oxygen system supplies either 100% oxygen to a demand valve in a or pulses of oxygen to the mask. Switching is automatic during a parachute descent. The system includes a valve manifold that is responsive to ambient pressure such that at low pressures it is configured to deliver gas from either an oxygen cylinder or an aircraft supply line to the mask demand valve and at higher pressures it is configured to deliver gas from the cylinder to a pulse gas delivery system. The mask also includes an inhalation valve that is closed if oxygen is supplied to the demand valve. Otherwise, the inhalation valve opens to allow ambient air to be drawn in and the pulse gas delivery system delivers a pulse of oxygen in response to the onset of inhalation.

An oxygen system supplies either 100% oxygen to a demand valve in a or pulses of oxygen to the mask. Switching is automatic during a parachute descent. The system includes a valve manifold that is responsive to ambient pressure such that at low pressures it is configured to deliver gas from either an oxygen cylinder or an aircraft supply line to the mask demand valve and at higher pressures it is configured to deliver gas from the cylinder to a pulse gas delivery system. The mask also includes an inhalation valve that is closed if oxygen is supplied to the demand valve. Otherwise, the inhalation valve opens to allow ambient air to be drawn in and the pulse gas delivery system delivers a pulse of oxygen in response to the onset of inhalation.

The present invention provides a system which allows a hose apparatus to be used to deliver water and air to the user at all times, eliminating the need for users to rely on breathable gas supplied by tanks. The invention includes the use of a breathable gas hose in the interior of the jacket of the water hose such that both breathable gas and water are delivered through the hose apparatus simultaneously. The breathable gas hose is protected within an outer jacket surrounding the water hose. The system allows for easy connect and disconnect of the air supply to the user's breathing apparatus and can be used with standard self-contained breathing apparatus (SCBA) typically used by firefighters. The system, however, overrides the SCBA system such that the user does not have to manually switch between the breathable gas and water hose apparatus and an SCBA system.