Oxygen Tanks and How to Choose One

Medically Reviewed by Carmelita Swiner, MD on December 03, 2022
5 min read

Do you need oxygen therapy for your lung condition? You have a few choices in oxygen systems. These include devices you use only at home and lightweight tanks you can take with you when you go out.

You’ll choose a system based on:

  • How often you leave the house or travel
  • If you need to go up and down stairs
  • Your size, endurance, and physical strength
  • If you tend to breathe through your nose or mouth
  • How much oxygen flow your doctor prescribes


You can choose from four main types:

Compressed gas system. You’ll use this system at home. It ­includes a stationary oxygen concentrator with a 50-foot tube. When you go out, you carry a portable tank. A supplier can deliver this to you prefilled, or you can refill it from your concentrator. When you go out with your portable tank, you’ll use an oxygen conserving device (OCD). It supplies small, pulsed doses to help your portable tank last longer.

Home oxygen concentrator. Also called a standard oxygen concentrator, this system sits in your house and plugs into an electrical outlet. It draws in air from the room, removes nitrogen and impurities, and gives you pure oxygen. You don’t need to order tanks from a supplier with this system, because it uses your home’s air.

Liquid oxygen system. This type also uses a portable tank. You refill it from a stationary home tank called an oxygen reservoir. The reservoir comes with a 50-foot tube that you can use when you’re at home. The tanks are very cold, so you have to be careful when you handle them. Your delivery company will refill your tank about every 2 weeks.

Portable oxygen concentrator (POC) system. You can carry this small, electric-powered device around with you -- even on an airplane. Either strap it to your back or pull it behind you on wheels. You’ll need a tube with a maximum length of 7 feet to deliver the oxygen. POCs run on either regular electricity or batteries. You can charge them anywhere, even in a car. You don’t have to refill them, and you can take them where they’re needed.

If you need to be able to move around with your oxygen, you can choose either a portable or ambulatory tank. Portable tanks are ones you can easily move around your house. But they often weigh more than 10 pounds, so they can be too heavy for you to carry when you go out.

Ambulatory tanks are small aluminum cylinders or liquid oxygen containers that you use with an OCD. They weigh less than 10 pounds. As the name suggests, they’re designed so you can carry them with you as you walk around. They last about 4-6 hours if they’re set to put out 2 liters of oxygen per minute.

Your doctor may suggest that you keep an E tank in your home. This is a large, heavy tank that you can use as a backup during power outages or if there are problems with your delivery.

How do you breathe from your system or tank? They deliver air in different ways:

Nasal cannula. Many people use a cannula. This plastic tube puts oxygen into your nostrils through two soft, hollow prongs. You hook it over your ears to hold it in place and connect it to a tube attached to your tank.

Face mask. If you need more oxygen, you may choose to use a face mask held in place by an elastic strap. These may also be good if you need more humidity or if you can’t use the nasal cannula.

Transtracheal catheter. This method puts air directly into your windpipe through a small opening in your neck called a stoma. You can hide it under your shirt or a scarf if you don’t want people to see it. You may need to use a humidifier attachment with it to add moisture, because the oxygen flower is higher, which can be drying. You’ll also need to keep your stoma clean to avoid infection.

Your doctor will prescribe the flow you need for your lifestyle as part of your therapy. Flow is measured in liters per minute.

If your doctor prescribes a higher rate of flow (4 liters per minute or more), you’ll need equipment that offers oxygen in a continuous flow, not pulses. An OCD may not give you enough. Stationary concentrators may provide a very high flow rate of up to 10 liters per minute.

Since higher rates of flow can be more drying, using certain cannulas, masks, or humidifiers can help make you more comfortable. You can also talk to your doctor about using a nasal moisturizer or nasal spray.

For lower flow, a portable oxygen concentrator may be right for you. Ask your doctor or respiratory therapist if a POC will give you enough oxygen.

Moisture boost: You can attach a humidifier bottle to your oxygen therapy device to make your airways feel less dry. You’ll need a humidifier if you use it with a continuous flow of more than 4 liters per minute.

With some therapy systems, a supplier will come regularly to your home with refills. It’s necessary to deliver liquid oxygen and some compressed gas systems. Your supplier can bring portable tanks to you and pick up the empty tanks. Home concentrators use the air in your house, so they don’t need to be delivered.

Prices for different systems or devices vary. Liquid oxygen tends to be more expensive than other types.

Your cost usually depends on your insurance coverage. Some policies may pay for all your therapy, but you may need to use certain brands or suppliers.

To be safe when you use your therapy devices, follow these tips:

  • Don't smoke. Tell others not to smoke around you, and stay away from smoky spaces when you go out. More oxygen in the air can make it easier for things to catch on fire. This also means that using candles and matches can be dangerous.
  • Keep oxygen devices at least 5 feet away from stoves, cooktops, open flames, heaters, and electronic devices.
  • Avoid flammable liquids or cleaners when you use your device.
  • Use water-based moisturizer, not oil-based, on your lips, mouth, or nostrils.
  • Don’t drink alcohol or take anything that might affect your breathing rate while using oxygen.
  • Talk with your doctor or nurse about how to clean your cannula, face mask, humidifier bottle, or catheter. Clean and replace them as recommended by your doctor.
  • Order your tanks or refills with plenty of time for delivery so you don’t run out.
  • Don’t change your device’s flow rate unless your doctor tells you it’s OK.