Abstract: This disclosure provides an oxygen delivery and reclamation system that supplies breathable oxygen-enriched gas to one or more users in a chamber. The one or more users receive oxygen at specified oxygen level setpoints. Exhalation air from the one or more users may be purged from the breathing loop using one or both of a recycle pump and an electronically actuated valve. Exhalation air in a purge line and optionally chamber air pulled from the chamber may be recycled using an oxygen concentrator. The oxygen concentrator generates oxygen-enriched gas and oxygen-depleted gas, where the oxygen-enriched gas may be delivered back to one or more users in the chamber.

Abstract: This disclosure relates to a regenerable, heat-abating, humidity-neutralizing, carbon dioxide removal system for a self-contained breathing apparatus. The self-contained breathing apparatus can include a carbon dioxide removal unit that scrubs carbon dioxide out of exhaled air from a user to provide humidified, scrubbed exhaled air. The self-contained breathing apparatus can further include a heat and humidity removal unit that is configured to receive the humidified, scrubbed exhaled air, and is configured to remove water vapor and heat associated with the water vapor from the humidified, scrubbed exhaled air in order to provide cooled, dehumidified inhalation air. The cooled, dehumidified air can be supplemented with oxygen and returned to the user at a comfortable temperature. In some implementations, the heat and humidity removal unit can replace conventional heat exchange and energy storage units, including heat exchange and energy storage units that use phase change materials.

Abstract: This disclosure relates to a regenerable, heat-abating, humidity-neutralizing, carbon dioxide removal system for a self-contained breathing apparatus. The self-contained breathing apparatus can include a carbon dioxide removal unit that scrubs carbon dioxide out of exhaled air from a user to provide humidified, scrubbed exhaled air. The self-contained breathing apparatus can further include a heat and humidity removal unit that is configured to receive the humidified, scrubbed exhaled air, and is configured to remove water vapor and heat associated with the water vapor from the humidified, scrubbed exhaled air in order to provide cooled, dehumidified inhalation air. The cooled, dehumidified air can be supplemented with oxygen and returned to the user at a comfortable temperature. In some implementations, the heat and humidity removal unit can replace conventional heat exchange and energy storage units, including heat exchange and energy storage units that use phase change materials.