Abstract: An oxygen enrichment and concentration system draws air from the ambient atmosphere and includes a set of primary adsorption beds and a set of secondary adsorption beds to adsorb components of the air other than oxygen. A blower and valves connected between the primary adsorption beds and the secondary adsorption beds alternatively direct the flow of air through one or the other bed of each set of adsorption beds. The enriched and concentrated oxygen product is stored in a storage vessel. A purge conduit connects the outlet of each of the secondary adsorption beds with the outlet of another secondary adsorption bed and the outlet of one of the primary adsorption beds so a small portion of the purified product from one adsorption bed is directed in a reverse direction through the other adsorption bed of the secondary set and the adsorption bed of the primary set to cleanse the adsorption material.