Generators using PSA technology require air compressors, dryers and filters. The pressure is used to get the right air pressure into the oxygen generator. Dryers and filters are used to cool the compressed air, remove dirt, water and oil before entering the oxygen generator. The oxygen generator uses positive pressure to extract pure oxygen from the compressed air.

Generators that use VSA technology, do not use air compressors, dryers or filters. VSA generators use a blower that drives air in and out of a cylinder with a low operating pressure sieve. The oxygen produced can then be pressurized with a booster compressor. This technology uses less energy than the PSA technology.