A process and apparatus to preclude unfiltered atmospheric gases and the products of human respiration including carbon-dioxide (CO.sub.2) with carbon-14 (.sub.14C) from contaminating greenhouse atmospheric gases which has utility in growing agricultural products with a reduced abundance of .sub.14C are disclosed. Agricultural products with reduced .sub.14C content can be grown in greenhouses with filtered atmospheric gases for the benefit of reducing harmful damage to human DNA. Agricultural production in greenhouses still requires humans to plant, maintain, and harvest crops in many cases. The process and apparatus allow for humans to access, work, and operate in these controlled environments without contaminating the atmospheric gases and agricultural products therein with respiration products and unfiltered atmospheric gases containing radioactive .sub.14C.

The present disclosure relates generally to respirators where inhaled air and exhaled air are separated into different channels to permit a user to always inhale fresh air. The respirators described herein can filter inhaled air, and optionally exhaled air.

The present disclosure relates generally to respirators where inhaled air and exhaled air are separated into different channels to permit a user to always inhale fresh air. The respirators described herein can filter inhaled air, and optionally exhaled air.

A respirator (10) having an oral-nasal unit (12) with a peripheral seal that seals around the nose and mouth of a wearer's face and having an inlet aperture (40) connectable to a supply of breathable air, and an outlet aperture (42). The unit having a rigid insert (106) with an exterior profile adapted to seat against a correspondingly shaped interior surface of the unit (12); an outlet conduit (112) with a tube adapted to extend through the exhale aperture (40) of the unit (12); and a wing portion (110) with a through aperture (122) registering with the unit's inlet aperture (40). The outlet conduit (112) having a bayonet connector (130, 132) that enables the unit to interchangeably and detachably connect to, a connector formed as part of an exhale aperture of a full-face mask, or of a harness assembly (102). The bayonet connector forms an airtight seal between the two.

A respirator (10) having an oral-nasal unit (12) with a peripheral seal that seals around the nose and mouth of a wearer's face and having an inlet aperture (40) connectable to a supply of breathable air, and an outlet aperture (42). The unit having a rigid insert (106) with an exterior profile adapted to seat against a correspondingly shaped interior surface of the unit (12); an outlet conduit (112) with a tube adapted to extend through the exhale aperture (40) of the unit (12); and a wing portion (110) with a through aperture (122) registering with the unit's inlet aperture (40). The outlet conduit (112) having a bayonet connector (130, 132) that enables the unit to interchangeably and detachably connect to, a connector formed as part of an exhale aperture of a full-face mask, or of a harness assembly (102). The bayonet connector forms an airtight seal between the two.

An integrated manifold system combines in a single, compact, unitary assembly a one-piece, machined manifold for connecting air supply cylinders with a first stage regulator and recharge port. The manifold body has at least one bottle port configured to removably receive a bottle of pressurized air, a first stage regulator chamber, a quick disconnect fitting port, an air channel in fluid communication with the at least one bottle port and the first stage regulator chamber, and an outlet channel in fluid communication with the first stage regulator chamber.

An integrated manifold system combines in a single, compact, unitary assembly a one-piece, machined manifold for connecting air supply cylinders with a first stage regulator and recharge port. The manifold body has at least one bottle port configured to removably receive a bottle of pressurized air, a first stage regulator chamber, a quick disconnect fitting port, an air channel in fluid communication with the at least one bottle port and the first stage regulator chamber, and an outlet channel in fluid communication with the first stage regulator chamber.

An emergency oxygen system for aircraft comprising: a breathing gas supply circuit to be connected upstream to a source of breathing gas and downstream to at least one mask, a flow control valve configured to adjust the flow of breathing gas supplied to the mask, an electronics board configured to control the flow control valve, a power source, a switching device interposed between the power source and the electronics board, the switching device comprising a switch configured to have a first state in which power from the power source is supplied to the electronics board and a second state in which the electronics board is not supplied with power from the power source.

An emergency oxygen system for aircraft comprising: a breathing gas supply circuit to be connected upstream to a source of breathing gas and downstream to at least one mask, a flow control valve configured to adjust the flow of breathing gas supplied to the mask, an electronics board configured to control the flow control valve, a power source, a switching device interposed between the power source and the electronics board, the switching device comprising a switch configured to have a first state in which power from the power source is supplied to the electronics board and a second state in which the electronics board is not supplied with power from the power source.

A SCBA with an air storage, a face piece with inner mask (nose cup), breathing regulator(s), a breathing valve, an exhalation valve operating at positive pressure relative to the ambient and a reservoir capable of storing the first part of an exhalation and delivering that part at the subsequent inhalation. The reservoir is positioned in the SCBA's face piece or in close proximity thereto, is in fluid contact with the inner mask, and has a shut-off valve controlled by a carbon-dioxide sensor. The operating pressure of the reservoir is maintained above ambient pressure and the operating pressure of the reservoir is between the opening pressure of the SCBA's breathing valve and the SCBA's exhalation valve.