Abstract: A normobaric hypoxia trainer including a training chamber, an intake fan for allowing ground level air to be introduced into the training chamber; an exhaust fan for removing air from the training chamber; a plurality of circulation fans for mixing interior air of the training chamber to create a uniform oxygen concentration within the training chamber; a nitrogen generation system, the nitrogen generating system including a plurality of polysulphone membrane cartridges for separating out nitrogen from air; a compressor for supplying compressed air to the nitrogen generation system; a pressure regulator for regulating the pressure of the compressed air; a heater for controlling temperature of the compressed air, the heated pressure regulated compressed air passing through the polysulphone membrane cartridges such that nitrogen can be separated out from the air; and, a flow controller for controlling flow rate of the separated nitrogen into the training chamber.