Oxygen Concentrators Explained: Types, Flow Rates & Portable Options for Home Use

What are oxygen concentrators?

An oxygen concentrator takes in room air, removes most of the nitrogen from it, and delivers concentrated oxygen to the user. Unlike a cylinder, it never needs refilling — as long as it has power, it keeps producing oxygen.

They are used at home, in aged care and nursing homes, and in medical centres and hospitals, for people with chronic or acute respiratory conditions. In Australia, all oxygen concentrators require a medical prescription.

Portable and stationary concentrators

Concentrators fall into two broad groups.

• Stationary concentrators stay in one place and run from mains power. They are larger and heavier, and they deliver higher flows — typically up to 5 or 10 litres per minute.
• Portable concentrators are light enough to carry and run on rechargeable batteries as well as mains and car power. Most weigh between 2 and 5 kilograms.

Many people who use oxygen at home end up with both: a stationary unit for overnight and resting use, and a portable for going out.

If you are not sure which suits you, we also hire concentrators, which is a practical way to try a machine before committing to a purchase.

Continuous flow and pulse dose — what is the difference?

This is the question we are asked most often, and it is also the one most often misunderstood.

Continuous flow delivers oxygen steadily, all the time, whether you are breathing in or out. It is measured in litres per minute (LPM), so a setting of 2 means 2 litres every minute, continuously.

Pulse dose senses the start of each breath and delivers a measured burst of oxygen only as you breathe in. Nothing is delivered while you breathe out. This is far more efficient, which is what makes small, light, battery-powered portables possible.

The critical point — and the one that causes the most confusion, including among some clinicians — is that a pulse dose setting is not a flow rate. A pulse setting of "2" does not mean 2 LPM, and it does not deliver the equivalent of 2 LPM continuous flow. Pulse settings are device-specific index numbers, and the actual volume delivered at the same number differs from machine to machine.

Choosing between them, and understanding what your setting number actually means on a given machine, deserves more space than this page gives it. We have written a detailed guide on continuous flow vs pulse dose oxygen concentrators, covering how each method works, when pulse dose is and is not appropriate, how your setting is determined, and what to ask your clinician.

What flow rate or setting do I need?

Your setting is not something you or we choose — it is measured, by a clinician, in a process called titration. They check what your oxygen saturation actually does at a given setting while you are sitting, walking, and asleep if you need oxygen overnight.

Because pulse settings vary between machines, it is worth asking your clinician for your requirement in millilitres per dose or millilitres per minute, not just as a setting number. That figure transfers between machines; a dial number does not. If you tell us your figure, we can tell you what each unit in our range actually delivers and how it compares.

Where can I buy an oxygen concentrator or spare parts?

Our full range is in oxygen concentrators, along with accessories and parts including spare batteries, external chargers, car adaptors, filters and cannulas.

We also service and repair concentrators. If you are in Sydney we can arrange a demonstration, either at your place or at our offices.

Why buy from Mega Medical?

We supply both portable and stationary units, we stock the consumables and spares for them, and we support what we sell — including servicing and repair if something goes wrong. If you would like help working out which machine matches your prescription, call our team on 1300 881 824 and we will go through it with you.