Is e inneal dùmhail ocsaidean a tha ag amas air an ocsaidean bho sholar gas (mar as trice èadhar cho-ioichte) le bhith a 'toirt air falbh Nitrogen gus sruth gas toraidh ocsaidean a thoirt seachad. Faodaidh againn an concentrator ogsaidean a bhith airson cleachdadh meidigeach no dachaigh.