Abstract: An air regenerator is provided comprising, in a cylindrical duct 4 communicating laterally with filtering cartridges 5, a venturi 1 whose outlet horn 1a is connected to a regenerated air outlet tube 3.The end of the inlet horn 1a is open and emerges inside duct 4. At a given distance with respect to horn 1b emerges a nozzle 2 whose mouthpiece is bored with a calibrated orifice of a diameter between 0.15 and 0.25 mm and whose thickness at the position of the bore is at most equal to the diameter of the orifice.The regenerator having such a nozzle connected to a pressurized oxygen cylinder is capable of sucking large amounts of air so that the voluminal yield expressed by the ratio of the volume of regenerated air to the volume of injected oxygen easily exceeds 37.