How do you get more oxygen?

Exercise with Oxygen Therapy involves an oxygen concentrator that generates higher concentrations of oxygen by separating oxygen from nitrogen filtering and purifying ambient air, providing you with a consistent supply of 90-95 percent oxygen.

Wondering how? 

The atmospheric air is typically 78% Nitrogen and 21% Oxygen. The remaining 1% is composed of a blend of carbon, helium, methane, argon and hydrogen. Oxygen concentrator works by absorbing nitrogen from the ambient air and leaving the concentrated oxygen of 90-95% purity, about 4x times as much oxygen as ambient air. 

The oxygen machine takes in the ambient air and filters it. The filtered air is then compressed by a compressor. This compressed air moves to the sieve bed filters, an important part of the device that deals with the removal of nitrogen from the air. The sieve bed filters are composed of zeolite, a material which is capable of filtering out nitrogen. An oxygen concentrator is equipped with two sieve beds. After the air is compressed, it reaches the first sieve bed and oxygen is transported to the product tank and Nitrogen gets filled up in the first sieve bed. Next, the air flow is switched and the compressed air is transported to the second sieve bed. A small amount of oxygen and surplus nitrogen from the first sieve bed filter is sent back to the atmosphere. The process switches back when the second sieve bed gets filled with nitrogen. This ensures the continuous flow of concentrated oxygen into the product tank. A pressure valve is provided for the regulation of oxygen supply in a wide range of 0.5-10 liters per minute.