Portable and home oxygen concentrators are designed to be self-sufficient. They produce their own oxygen, alarm you if something is wrong with the machine, and they can alarm you if they don't detect a breath. To produce its own oxygen, a concentrator draws in ambient air through a gross-particle filter and sends it through a filtration process to produce and compress medical grade oxygen. The one aspect where a concentrator is not self-sufficient is with its filters. Cleaning your oxygen concentrator's filters is an absolute must. If you go without cleaning your filters you risk damaging the unit and possibly voiding the warranty of your machine.