An Oxygen Concentrator (also sometimes called “oxygen generator”) is a medical device used to deliver oxygen to those who require it. People may require it if they have a condition that causes or results in low levels of oxygen in their blood. These oxygen concentrators are normally obtained via prescription and therefore cannot be purchased over the counter. Oxygen concentrators are powered by plugging into an electrical outlet or by a battery. If the concentrator is powered by an electric battery, that battery will need to be charged by plugging into an outlet. Several parts make up a concentrator, including a compressor, sieve bed filter, and circuit boards.

An oxygen concentrator has a compressing element, but it should not be confused with compressed oxygen or an oxygen tank. Whereas a tank has a set amount of oxygen that it dispenses, a concentrator filters in air, compresses it, and delivers air continuously. The air supply will never run out. Instead of refilling compressed air, the concentrator just needs access to power.