What is the difference between pulse and continuous flow?

When considering which portable oxygen concentrator is best, the first thing you need to determine is whether you need a continuous flow of oxygen or if a pulse flow is sufficient.

Continuous flow means the concentrator is producing oxygen continuously whether you are breathing (inhaling) or not. All home/stationary concentrators provide a continuous flow of oxygen.

Pulse flow, also called pulse dose or on-demand, means that the concentrator produces oxygen only when it is triggered by the user’s inhalation (breathing in). When you inhale through the cannula it causes negative air pressure which triggers the concentrator to send a bolus (or puff) of oxygen right at that moment. The concentrator then rests while you are exhaling (breathing out). The concentrator is able to do this through the use of a built-in oxygen conserver, much like those used on oxygen tanks.

When used on an oxygen tank, a conserver does just what its name implies: it conserves the oxygen in the tank, allowing it to last three to five times longer than continuous flow. When placed in a portable concentrator, the conserver allows the machine to produce oxygen at a smaller capacity, but still providing an equivalent amount of oxygen at each setting. By placing a conserver inside an oxygen concentrator, manufacturers have been able to greatly reduce the size of the concentrator, thus allowing for portable oxygen concentrators; and in a portable oxygen that offers both continuous and pulse flow, choosing the pulse flow setting increases the usable battery time.

For more information, please see THIS ARTICLE.