The present disclosure describes a system and method for maintaining oxygen purity in portable oxygen concentrators, even with asymmetric generation of oxygen enriched gas volumes from different sieve beds of the concentration system. The present system and method compensate for asymmetric oxygen enriched gas generation using asymmetric delivery of purge volumes. Purge valves are used to deliver the asymmetric purge gas volumes, enables the system to maintain oxygen purity without additional power consumption, even when a portable oxygen concentrator does not include a product tank. The present system and method are configured such that asymmetry in enriched oxygen generation can be monitored and the asymmetric purge gas compensation can be applied independently from other control mechanisms of a portable oxygen concentrator.

A method and system of responding to adverse environmental conditions local to a user of an oxygen concentrator is disclosed. Physiological data of the user is collected. Operational data of the oxygen concentrator is collected during operation of the oxygen concentrator. Environment data local to the oxygen concentrator is collected. Based on the collected environmental data, it is determined whether adverse environmental conditions exist local to the oxygen concentrator. The collected physiological, operational, and environmental data are analyzed to determine a responsive action to the determined adverse environmental conditions. The responsive action is communicated to the user.

Apparatuses, systems, and methods are provided for a breather for a reservoir is provided, including a housing including a plurality of valves, the plurality of valves including (i) at least one valve in a first configuration configured to permit fluid communication from an interior portion of the housing with air outside the reservoir, and (ii) at least one valve in a second configuration configured to permit air to selectively pass between outside the breather and an interior portion of the breather. The breather further includes a plurality of first openings in the housing configured to be in fluid communication with air outside of the reservoir, a second opening of the housing configured to be in fluid communication with air inside the reservoir, and desiccant positioned within the housing.

Oxygen concentrator methods and apparatus estimate sieve bed effective capacity. Estimation applies function(s) to a parameter of a measured pressure-time characteristic of the bed, characteristic of a phase of an adsorption cycle of the concentrator at a predetermined motor speed of its compression system. Estimation may involve operating the concentrator at a predetermined bed pressure and measuring a mass flow of gas entering or exiting the bed, and may use the measured mass flow and one or more functions. Estimation may involve a measured bed exhaust mass flow for a purge phase when bed pressure is regulated to maintain a predetermined target pressure using motor speed adjustment. The estimation may apply exhaust mass flow function(s) to the measured exhaust mass flow. Estimation of the effective capacity may involve applying motor speed function(s) to measured motor speed, such as an adjusted one for regulating canister pressure to achieve a target pressure.

A method and exhaust gas treatment system for treating an ammonia-containing exhaust gas, for example a livestock house exhaust gas. The exhaust gas treatment system comprises a plurality of sorbent beds comprising a copper-doped small-pore zeolite, a valve system configured to establish independently for each sorbent bed fluid communication in a first or second configuration, wherein in the first configuration a flow of ammonia-containing exhaust gas contacts the sorbent bed at a temperature of less than 50° C. for storing the ammonia; and in the second configuration a flow of heated gas maintains the sorbent bed at a temperature of at least 300° C. for releasing and treating the ammonia in situ.

A hybrid nitrogen gas generation system includes a membrane nitrogen gas generator and a pressure swing absorption nitrogen generator. A gas comprising nitrogen is purified to a first nitrogen purity using one of the membrane nitrogen gas generator and the pressure swing absorption nitrogen generator. The gas is either bypassed around the other of the membrane nitrogen gas generator and the pressure swing absorption nitrogen generator to provide the gas having the first nitrogen purity or the gas is purified to a second nitrogen purity using the other of the membrane nitrogen gas generator and the pressure swing absorption nitrogen generator.

A passive valve for use as a fixed leak valve. The valve includes a body having an internal chamber, first and second body ports in fluid communication with the chamber with the first port configured for fluid communication with a patient connection and the second body port configured for fluid communication with a ventilator, a body passageway in fluid communication with the chamber and with ambient air exterior of the body, and a check valve seal positioned to seal the body passageway to permit the flow of gas within the chamber through the body passageway to the exterior of the body and to prevent the flow of ambient air exterior of the body through the body passageway into the chamber. In alternative embodiments, the valve is incorporated into the patient connection or constructed as a separate part connectable to the patient connection.

A pressure swing adsorption (PSA) system and methods for controlling each PSA cycle performed by the PSA system to produce oxygen enriched gas during productive portions of a user breathing cycle, and to cease production of oxygen enriched gas during non-productive portions of the user breathing cycle, is provided. The PSA system synchronizes PSA cycle phases including adsorption and desorption phases with a user's individual inhalation and exhalation phases, on a breath by breath basis, such that each PSA cycle can be dynamically varied from a succeeding PSA cycle, in real time in response to variations in the user's breathing cycle. An oxygen delivery device including a breathing cycle sensor provides breathing cycle inputs to a controller for use with at least one algorithm to detect breathing flow phases during each user breath, and to synchronize each PSA cycle to the user's breathing flow phases, on a breath-by-breath basis.

A wheel lock or clip for maintaining position of a thumbwheel or wheel of a rotary actuated delivery device includes an arcuate or curved body having a live hinge extending therefrom, the hinge connected to an arm having an engagement tooth extending therefrom. The tooth is operatively connected to tab for actuation by a user to disengage the engagement tooth from teeth of gear or barrel of a wheel or a thumbwheel of the rotary actuated device to thereby allow free movement of the wheel or thumbwheel.

Embodiments of gas concentrating systems and methods are provided. These systems and methods comprise configuration of hardware and software components to monitor various sensors associated the systems and methods of concentrating gas as described herein. These hardware and software components are further configured to utilize information obtained from sensors throughout the system to perform certain data analysis tasks. Through analysis, the system may, for example, calculate a time to failure for one or more system components, generate alarms to warn a user of pending component failure, modify system settings to improve functionality in differing environmental conditions, modify system operation to conserve energy, and/or determine optimal setting configurations based on sensor feedback.