50 the circuit board 50 is preferably sealed to the housing with foam to prevent air leakage back across the air barrier the air flow through the body is shown in a particular as built embodiment the absorber columns are in the input side of the barrier and the compressor is in the output side of the barrier when assembled the panels and barrier constitute a very rigid shell with controlled noise airflow that is particularly suited to an oxygen concentrator where room air must be drawn into the system as a source of oxygen and the nitrogen rich exhaust gas must be expelled from the concentrator it is advantageous to separate these gas streams so that there is no excess nitrogen drawn into the air inlet of the compressor referring to fig6 a b and c details of the compressor side of the novel concentrator are shown in the exemplary version depicted a compressor bracket 64 is mounted to panel 33 bracket 64 is preferably mounted to panel 33 with shock vibration isolating elements which in the exemplary version shown are rubber feet 65 feet 65 preferably have a durometer between 20 a and 60 a compressor 62 is in turn mounted to bracket 64 with another set shock vibration isolation elements providing two levels of isolation in the exemplary version.