What’s the Difference between an Oxygen Regulator and an Oxygen Sensor?

Supplemental oxygen therapy can be delivered in three ways: via oxygen concentrator, compressed oxygen gas or liquid oxygen. Many oxygen concentrators contain an oxygen sensor, while oxygen tanks work by using an oxygen regulator. The difference between these two methods is explained in the following text.

Oxygen Concentrators

oxygen regulator, oxygen sensor, oxygen concentrator

The least expensive, in the long-term, and most effective way to deliver supplemental oxygen without refills is through an oxygen concentrator.[1] Oxygen concentrators come in many different sizes with the smallest portable unit weighing less than two pounds. Some oxygen concentrators come with one or multiple oxygen sensors to detect the percentage of oxygen being delivered to the patient, while other units can be purchased with or without an oxygen sensor.

Compressed Oxygen Gas

Compressed oxygen gas is stored in oxygen cylinders that are usually made of steel or aluminum. Because oxygen in these tanks is stored in the form of pressurized gas, the canisters must be kept upright and handled with care. As the oxygen flow rate of the patient increases, the tanks increase in size. Oxygen tanks are bulky, heavy and have to be refilled or changed frequently. They also contain pressure valves that have to be checked regularly.  The oxygen in the tank is delivered to the patient at 100% concentration.[2] The oxygen tank is also equipped with an oxygen regulator that regulates the amount of oxygen delivered to the patient. 

Liquid Oxygen

A liquid oxygen supply system consists of a bulk storage unit or reservoir that is housed in the home and a small, portable unit you can carry around with you. Both units have a design similar to that of a thermos bottle, consisting of a container inside another container separated by a vacuum. Liquid oxygen is also delivered to the patient at 100% concentration, and may incorporated an oxygen conserving device, also known as an oxygen regulator, to regulate the flow of oxygen to the patient.[3]

One of the biggest perks of using liquid oxygen is that it uses no electricity and can deliver high flows of oxygen for a longer period of time. However, liquid oxygen systems are getting more difficult to obtain.

So how are oxygen regulators and oxygen sensors different? Here is how they function, depending on the kind of oxygen delivery system you’re using.

Oxygen Regulators

Oxygen regulators, which are sometimes referred to as oxygen conserving devices (OCDs), are used to regulate the flow of oxygen from a portable cylinder of compressed oxygen gas or a liquid oxygen system to the oxygen tubing and nasal cannula or oxygen face mask used to breathe in the oxygen. Oxygen regulators release compressed or liquid oxygen from an oxygen tank in a continuous mode measured in liters per minute (LPM).[4] Oxygen regulators are essential for ensuring that you are receiving the correct amount of oxygen.

The oxygen regulator unit consists of a dual pressure gauge that measures oxygen left in the cylinder and the outgoing oxygen pressure flow. It also has a valve connector for connecting an oxygen mask or nasal cannula. The oxygen regulator is adjusted by using a knob device that can adjust the flow of oxygen through the regulator.

Oxygen Sensors

Many portable oxygen concentrators, including the Inogen One G4, are equipped with an oxygen sensor. Oxygen sensors detect the percentage of oxygen in the air being delivered to the patient. Placing oxygen sensors at various points in your oxygen concentrator, like between the oxygen regulator and oxygen outlet at points within the filtering portion of the concentrator, ensures proper compression, purification and delivery of oxygen. Internal oxygen sensors cause the oxygen concentrator to alarm should the oxygen concentration drop below a therapeutic range.[5] Because an oxygen sensor has an alarm and can alert you to problems with your oxygen delivery, many patients may feel more comfortable with an oxygen sensor than with an oxygen regulator.

Setting Up Your Oxygen Equipment in Your Home

Whichever oxygen delivery method you decide upon, you must choose an oxygen supply company to deliver it to your home. Once you choose your company and your oxygen supplies are delivered to your home, a specially trained respiratory technician will typically come to your house to help you set up the oxygen equipment. If you have chosen a compressed gas system or a liquid oxygen system, make sure you ask questions about how to use the oxygen regulator correctly and how to attach the oxygen regulator safely to your oxygen tanks.

How Inogen Can Help You

If you have chosen an oxygen concentrator and choose to go with an Inogen product, we offer a variety of resources to help you understand how the oxygen sensors in your concentrator work. We invite you to call us anytime to learn about your equipment and how the oxygen sensors in Inogen portable oxygen concentrators help ensure that you are receiving oxygen within a therapeutic range, as well as ensuring that you receive the right amount of oxygen for your prescribed therapy plan at all times.

Our Oxygen Specialists can walk you through learning how to check the purity of the oxygen produced by your Inogen portable oxygen concentrator. They can also teach you how to maintain and care for your oxygen concentrator properly, as well as what accessories to purchase, to make sure that it continues to provide the highest oxygen purity level possible and operates exactly as it should.


For more information about oxygen regulators, oxygen sensors and oxygen supplies, call an Inogen Oxygen Specialist at 1-800-374-9038.   


[1] University of Michigan. Oxygen Delivery Systems. Accessed February 28, 2018.

[2] Oxygen, Concentrator Store. What’s the Difference between an Oxygen Concentrator and an Oxygen Tank? Accessed February 28, 2018.

[3] Inogen. What is Liquid Oxygen? Accessed February 28, 2018.

[4] American Discount Home Medical Equipment. Oxygen Regulators and Conservers. Accessed February 28, 2018.  

[5] Servoflo. Pressure & Oxygen Sensors in Oxygen Concentrators. January 7, 2016.

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