Disclosed are methods and a safety system of a structure for automatic switching between sources of breathable air within the safety system in accordance with air parameter based automatic purging of a compromised form thereof. The safety system has a fixed piping system installed within the structure for supply of the breathable air from a source across the safety system. In response to an alert signal indicative of a sensed parameter of the breathable air being outside a predetermined threshold value, a breathable air purging system within the safety system automatically purges the safety system of the breathable air, and a bypass controller device automatically switches to another source of the breathable air to ensure a continued supply of the breathable air via the fixed piping system of the safety system.

A preflushing unit (10) preflushes a breathing gas circuit (210) of a closed-circuit respirator (200). A basic body (20) has an inlet port (22), feeding breathing gas from a breathing gas supply (220), an outlet port (24) discharging breathing gas into the breathing circuit, and a flow section (32) fluid connecting a valve chamber (30). A valve body (40) with a sealing surface (42) is arranged in the valve chamber (30). An elastomer body (50) with a counter-sealing surface (52) in the valve chamber, fluid tight separates the flow section from a control section (34). The counter-sealing surface acts with a sealing force against the valve body for sealing the flow section. A control port (26) of the basic body provides a controlled feed of breathing gas from the breathing gas supply into the control section for pressure equalization between the flow section and the control section.

A rescue tube comprising a tube having a first and second end, a one-way valve and a ported double swivel elbow; wherein the one-way valve and ported double swivel elbow are connected to one another, and the one-way valve is attached to the tube.

A rescue tube comprising a tube having a first and second end, a one-way valve and a ported double swivel elbow; wherein the one-way valve and ported double swivel elbow are connected to one another, and the one-way valve is attached to the tube.

A system (2000) comprising a head-mounted device (2010); at least one position sensor coupled to the head-mounted device; at least one light-filtering shield (2012) coupled to the at least one position sensor; at least one light detector (2019); and at least one computing device (2017) configured to receive, from the light detector, an indication that an intensity of light detected by the light detector exceeds an exposure threshold; determine, from the at least one position sensor, that the light-filtering shield is not positioned at the face of a worker to filter light with the intensity that exceeds the exposure threshold; and generate, in response to the determination that the light-filtering shield is not positioned at the face of a worker wearing the head-mounted device to filter light with the intensity that exceeds the exposure threshold, an indication for output.

A breathing gas delivery system comprising a gas flow controller, at least one breathing apparatus, and at least one first length of tubing coupling the breathing apparatus to the gas flow controller. The gas flow controller has a body having an on/off switch, at least one gas input, at least one gas output, and at least one control mechanism for controlling flow of gas to the gas output. The breathing apparatus comprises a T-shaped gas input, a breathing bag coupled to the T-shaped gas input, a second length of tubing having two opposed ends, wherein one end is coupled to the other arm of the T-shaped gas input, a filter coupled the second length of tubing, and a nasal assembly coupled to the filter.

A breathing gas delivery system comprising a gas flow controller, at least one breathing apparatus, and at least one first length of tubing coupling the breathing apparatus to the gas flow controller. The gas flow controller has a body having an on/off switch, at least one gas input, at least one gas output, and at least one control mechanism for controlling flow of gas to the gas output. The breathing apparatus comprises a T-shaped gas input, a breathing bag coupled to the T-shaped gas input, a second length of tubing having two opposed ends, wherein one end is coupled to the other arm of the T-shaped gas input, a filter coupled the second length of tubing, and a nasal assembly coupled to the filter.

A spring bridge (40), for a spring bridge breathing bag plate system (80) of a closed-circuit respirator (100), includes a spring bridge carrier (42) for the arrangement of at least one spring element (82) of a spring bridge breathing bag plate system (80) and at least one fastening element (44) for holding the spring bridge (40) at the closed-circuit respirator (100). The at least one fastening element (44) is a rotating element and/or a sliding element for the rotatable and/or sliding movement of the spring bridge carrier (42) at and relative to the closed-circuit respirator (100). A spring bridge breathing bag plate system (80) is provided for a closed-circuit respirator (100) as well as for a closed-circuit respirator (100).

This invention relates to a process and apparatus to preclude unfiltered atmospheric gases and the products of human respiration including carbon-dioxide (CO.sub.2) with carbon-14 (.sup.14C) from contaminating greenhouse atmospheric gases which has utility in growing agricultural products with a reduced abundance of .sup.14C. Agricultural products with reduced .sup.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. This invention provides a means 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 .sup.14C.

This invention relates to a process and apparatus to preclude unfiltered atmospheric gases and the products of human respiration including carbon-dioxide (CO.sub.2) with carbon-14 (.sup.14C) from contaminating greenhouse atmospheric gases which has utility in growing agricultural products with a reduced abundance of .sup.14C. Agricultural products with reduced .sup.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. This invention provides a means 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 .sup.14C.