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  A portable oxygen concentrator (POC) is a device used to provide oxygen therapy to people that require greater oxygen concentrations than the levels of ambient air. It is similar to a home oxygen concentrator (OC), but is smaller in size and more mobile. They are small enough to carry and many are now FAA-approved for use on airplanes. Medical oxygen concentrators were developed in the late 1970s. Early manufacturers included Union Carbide Portable Oxygen Concentrator [1]. They were initially conceived of as a method of providing a continuous source of home oxygen without the use of heavy tanks and frequent deliveries.[2] Beginning in the 2000s, manufacturers developed portable versions.[3] Since their initial development, reliability has been improved, and POCs have between one and which are not the same as liters per minute (LPM).[4] The latest models of intermittent flow only products weighed in the range of from 2.8 to 9.9 pounds (1.3 to 4.5 kg) and continuous flow (CF) un...