Portable Oxygen: A User's Perspective

Home Use:
Compressed, Liquid, or Concentrator?

The information here provided is for educational purposes only and it is not intended, nor implied, to be a substitute for professional medical advice. Always consult your own physician or healthcare provider with any questions you may have regarding a medical condition.   

Oxygen can be stored and delivered to users in compressed or liquid form. It can also be delivered as a concentrator creates it.
Compressed oxygen. Compressed oxygen is stored as a gas in cylinders for home  (image) and portable (image) use under a pressure of between 2,000 and 3,000 pounds per square inch (psi).  
Liquid oxygen. Oxygen turns from a gas into a liquid at -300o F, a temperature at which it can be stored in reservoirs for home use (image) and portable tanks, such as Helios (image) or the Escort (image), at a pressure of about 21 psi. Liquid oxygen takes about 10 percent of the space that is required by compressed oxygen.
Concentrator. A concentrator (image) does not store oxygen. It produces and distributes it continuously. It takes the air around it, which normally contains 21 percent oxygen, and removes the nitrogen.  If you want to know more about concentrators, see Concentrators: Portable & Transportable.
The oxygen produced by a concentrator is between 90 and 96 percent pure oxygen, whereas compressed and liquid oxygen are nearly 100 percent pure.

Home Use
About 80 percent of the users requiring home oxygen have concentrators and the rest use liquid oxygen. Bill H. from Nevada recently switched from using a concentrator to using liquid oxygen in his home. Listen to what he has to say about it.

I recently switched from a concentrator and use a liquid oxygen reservoir for oxygen needs at night. I'm glad I made the switch. Why?
  •  The concentrator used electricity and so was subject to power outages. No power, no concentrator. While the power was on, the concentrator used it up at the rate of about $30 a month.
  • The concentrator created heat. This was not a problem in the winter but during the summer months it made my air conditioner work harder, hence an even larger electrical bill. The reservoir requires no electricity.
  • The liquid unit makes no sound. Frankly, it was kind of spooky when I first switched over and shut down the concentrator. The silence was deafening.
There are some disadvantages to liquid.
  • I have to monitor the reservoir so I can change to a spare one or call for a delivery before I run out.

  • Since my reservoir is inside my home, I must be there when the supplier arrives to fill it--and they require quite a broad time window.
Bottom line here: I love the liquid system.

All three ways for providing medical oxygen can be used in the home. The one you have may be the one most easily serviced by your oxygen provider. As you look at the table below, picture yourself as an oxygen provider. Which way would you choose for your customers? Which one requires the least effort? The highest profit?
Table 1
Comparison of Home Systems

Compressed Oxygen
(H Cylinder)
Liquid Oxygen
(L-30 Reservoir)

Empty Weight (lbs.)
135 45
Full Weight (lbs.)
Duration (days)*
Monthly Power Cost
Noise Level (Db)*
*Continuous flow @ 2 Lpm
**See Sound Intensity

If you were an oxygen provider who used the above table for guidance, here is what you might envision.
compressed oxygen vs. liquid oxygen. If, as an oxygen provider, you chose compressed oxygen over liquid oxygen, you will have to make five times (12.5 divided by 2.3 = 5.4) the number of deliveries than you would if your chose liquid oxygen. To make the same number of delivers as you would with liquid oxygen, you would have to provide the user with five or more compressed cylinders. The total weight of five cylinders would be 750 pounds, a weight burden for your truck and for the user.
liquid oxygen vs. concentrator. If, as an oxygen provider, you chose liquid oxygen over a concentrator, you would make delivers at least every two or three weeks. During each deliver, your driver would have to move and possibly fill reservoirs, whereas, if you chose a concentrator, there would be a single delivery of equipment, weighing about 54 pounds, and maintenance visits, either quarterly or annually.
If your living quarters are small, or if you live where your air conditioner is used more than your furnace, you may have equally good reasons for choosing liquid oxygen instead of a concentrator.

Living with a concentrator in a small apartment or mobile home may not be very pleasant. For its noise at night, you may wish you could put the concentrator outside. It may vibrate the flooring, particularly in a mobile home, resounding through out your home. It will heat up your home comfortably during cold weather. If you live in Florida or other states where the main problem is cooling your home, you will spend extra on electricity cooling what the concentrator heats.

If Medicare is your primary, there is no price difference among the three for home use. According to the 2001 Medicare Fee schedule for Florida, the monthly copay for any of the three was the same,  $42.75.

So, if you currently use a concentrator and you have any of the complaints listed above, consider switching to liquid oxygen. Talk with friends who use liquid to find out how they feel about it. When you have made up your mind, tell your physician your reasons. He/she can order liquid oxygen as the form of oxygen for delivery in your home.

This story continues in the feature story for September, Portable Use: Compressed, Liquid, or Concentrator?

Have questions?
Email me. Let's talk. Tell me about your experiences with portable systems that use compressed or liquid oxygen.

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© 2003 Copyright 
Peter M. Wilson, Ph.D. 
Founder of PortableOxygen.org

You have permission to print this document for your personal use. You also have permission to print, copy, and distribute this document to oxygen users and their caregivers.

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