Big Market Research, Portable oxygen concentrator market size at $744 million in 2014 is expected grow to $2.2 billion by 2021. Browse more info @ http://www.bigmarketresearch.com/portable-oxygen-concentrators-shares-strategies-and-forecasts-worldwide-2015-to-2021-market
Market growth is a result of the aging of the population and the increased need for oxygen. Technology has achieved major breakthroughs for portable oxygen concentrator units.