Development
Portable oxygen concentrators have been around for decades; but the older versions were bulky, unreliable, and were not permitted on airplanes. Since 2000, manufactures have improved their reliability and they now produce anywhere between one and six liters per minute (LPM) of oxygen. The portable concentrators plug directly into a regular house outlet for charging at home or hotel; but they came with a power adapter that can usually be plugged into a vehicle DC adapter. They have the ability to operate from the battery power as well for either ambulatory use, or away from a power source, or on an airplane.
Read more about this topic: Portable Oxygen Concentrator
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