Setting An Oxygen Concentrator – Low-Flow And High-Flow Therapy

For low-flow oxygen therapy, an oxygen concentrator should be set at 1-2 LPM (depending on your prescription). In high-flow treatment, supplemental oxygen concentration depends on the type and severity of the respiratory disease. Always follow your doctor’s prescription regarding suitable oxygen levels when using at-home concentrators.

Many people experience debilitating lung health and need oxygen concentrators to help them breathe. In fact, more than 1.5 million adults across America rely on supplemental oxygen for survival and a better quality of life. So, it’s important to know how to set up and best use your oxygen concentrator.

This article how to set oxygen concentrators up, how different oxygen levels effect you, and why extra oxygen is as harmful as a depleted oxygen supply.

How Oxygen Concentrator’s work

Oxygen concentrators are medical devices for people with pulmonary (respiratory) issues.

Air contains 21% oxygen, while the rest of the mixture is made of other gases like nitrogen (78%), argon (0.9%), carbon dioxide etc.

Typically, the air we breathe travels through the respiratory tract that ends in tiny air sacs called alveoli. 13.1% of inhaled oxygen from the atmosphere diffuses into the blood capillaries surrounding the alveoli, whereas carbon dioxide from the blood is transferred into the lungs to be inhaled.

Oxygen is used to generate energy that is used by all the body’s vital organs.

Unfortunately, certain lung conditions like tissue damage, fluid buildup, spasms, etc., damage the lung’s ability to breathe in air.

Understandably, insufficient air implies oxygen depletion. While inhalers and CPAP devices are available for mild breathing issues, severe respiratory failure requires a more efficient supplementary system, and this is where oxygen concentrators come in.

Here’s how an oxygen concentrator works to help you breathe easier:

  • Once you connect the device to a power source, the compressor starts drawing air inside.
  • The compressor then adjusts the air pressure.
  • Then, the air is passed through two Zeolite sieve beds. Zeolite is a crystalline substance that separates nitrogen from oxygen.
  • The pure oxygen is sent to the cylinder. It is supplied to the patient via an oxygen mask or nasal tube.
  • The remaining air (nitrogen and other gases) not absorbed by Zeolite are vented into the room.

This loop continues in the presence of adequate air supply, and that’s how oxygen concentrators provide 90 to 95% pure oxygen to the patient.

Types Of Oxygen Concentrators

Based on the oxygen flow, there are two types of oxygen concentrators:

1. Continuous Flow

These concentrators supplies a preset dose of oxygen every minute unless turned off. This results in steady oxygen flow regardless of your activity.

2. Pulse Dose

These concentrators adapt to your breathing pattern and releases oxygen depending on your inhalation rate. In this way, the oxygen dose varies each minute.

Pulse dose is ideal for low-flow oxygen therapy, whereas continuous flow concentrators are prescribed for high-flow treatment.

Plentiful Air has a detailed guide to the different types of oxygen concentrators and their cost available here.

How To Set The Oxygen Flow Rate In Concentrators

For effective oxygen therapy, it’s important to set the correct flow rate in concentrators. Remember, oxygen therapy should only be received on a reliable doctor’s recommendation.

A prescription usually includes the LPM (Litre Per Minute) settings to keep oxygen saturation above 90%, the equipment compatible with your condition, and how long you need supplemental oxygen.

Low-Flow and High-Flow Oxygen Therapy

During rest or when using the concentrator for mild discomfort, 1 to 2 LPM is usually recommended. However, if your doctor decides you need a higher level, adjust the concentrator accordingly.

More than 4 LPM of oxygen is considered high. High-flow oxygen therapy treats fluid buildup in the lungs and improves atelectasis (partial or complete collapse of one or both lungs).

Whether you need low-dose or high-dose is decided based on your disease. For example, 60 LPM of oxygen has shown promising results in ICU patients with acute hypoxemic respiratory failure. However, to prevent oxygen toxicity, doctors ensure your oxygen level stays within the healthy range and does not exceed 110 mmHg.

With time, as the health condition progresses, the requirement for supplemental oxygen naturally increases.

When as a patient you start experiencing discomfort, shortness of breath, fatigue, and similar symptoms, healthcare providers will assess your oxygen levels with pulse oximeters or arterial blood tests (for critically ill people), with and without concentrators. Doctors may recommend a higher oxygen dose if your health appears unstable.

When Two Are Using The Concentrator

A single oxygen concentrator can be used by two people simultaneously through additional tubing. In this case, oxygen should be set at 3 to 4 LPM.

It is crucial to remember that once you go back to only the person using the concentrator, LPM should be reset to 1.5 to 2 (depending on your prescription). Also, ensure that the second tube and additional nasal cannulas are removed to ensure adequate oxygen levels.

Role Of Various Face Masks

It is essential to note that the type of mask used during the treatment also impacts the dose. Here are the different kinds of face masks:

  • Face Tent: It is a shield that encircles the face. Being loose, it does not supply proper levels of oxygen. Therefore, it is only recommended for non-cooperating patients who show irritability towards other options.
  • Clear Plastic Mask: This simple mask is secured on the patient’s face with a strap. It has short-port openings at the sides that allow exhaled air to escape into the room. Due to the ports, the air mixes with oxygen, and therefore, masks are not highly efficient.
  • Partial Rebreathing Mask: It comes with a reservoir bag that supplies moderate-to-higher oxygen concentrations. This also comes with side-port openings. You must ensure that the bag remains inflated; it may collect exhaled air.
  • Non-Breathing Mask: This includes one-way inspiratory and expiratory valves on top of a reservoir bag. It delivers a high oxygen concentration because the two valves alternately close to prevent air mixing.
  • Venturi Mask: This is a high-end, cone-shaped device with many entertainment ports at the base. The ports adjust themselves to supply different levels of oxygen. This mask is considered highly efficient because it delivers precise oxygen concentration.
  • Nasal Cannula: It consists of two prongs directly inserted into each nostril. This is primarily used for high-flow oxygen therapy.

For example, in the case of COPD, the following oxygen levels are recommended:

  • 3-4 LPM with Venturi mask
  • 1-2 LPM with nasal cannula

If you need to reset your concentrator, Plentiful Air has a guide available here.

Who Needs an Oxygen Concentrator

Normal oxygen saturation levels in the body are 95% or higher. At lower levels, people start experiencing labored breathing, fast heart rate, wheezing, sweating, and confusion – characterizing respiratory problems.

Oxygen concentrators are prescribed for people with mild to moderate oxygen depletion, i.e., 90 to 94%.

First, doctors check your arterial blood oxygen. The doctors usually suggest supplemental oxygen therapy via concentrators only if the oxygen level is 60 mmHg or lower (the ideal range is 75 to 100 mmHg).

Some of the conditions which oxygen concentrators are used for are:

  • Pneumonia
  • Asthma
  • Bronchopulmonary dyspnea
  • Chronic Obstructive Pulmonary Disease (COPD)
  • Covid-19
  • Trauma to the lungs or other parts of the respiratory tract

Patients suffering from extreme oxygen deficiency are not suited to oxygen concentrators.

This is because concentrators can supply 5 to 10 liters per minute, whereas patients with severe respiratory failure require higher oxygen flow. High-end equipment like cylinders is prescribed in such cases.

Benefits Of Oxygen Concentrators

Even mild respiratory dysfunction can be physically and mentally taxing. From mild headaches and nausea to confusion, behavioral changes, and restricted growth (in children), various health complications can result from oxygen depletion.

Concentrators are prescribed to ease the stress induced due to low oxygen. They can reduce headaches, irritability, and fatigue. It also improves the growth and development of children having congenital respiratory disorders.

A study found that continuous oxygen therapy increased the survival rate of COPD patients (they have progressive lung disorders).

Why Is It Crucial To Monitor Oxygen Supplementation In Concentrators?

Oxygen settings in a concentrator are the liters of oxygen dispensed by the device in a minute and the pressure of the gas. This amount is specifically prescribed depending on the severity of the condition and needs to be strictly monitored.

We know that oxygen depletion can lead to severe health complications. However, excess oxygen is also disastrous and results in oxygen toxicity.

Oxygen toxicity or hyperoxia develops after prolonged exposure to above-normal oxygen article pressures or very high partial pressures over a short span. It is characterized by coughing, throat irritation, chest pain, muscle twitching, blurred vision, and confusion.

Interestingly, many symptoms of oxygen toxicity are similar to low oxygen.

Here are the health effects of excess oxygen levels:

  • Oxidative Damage: Research shows that oxygen toxicity results in oxidative damage to the cell membranes. Excess free radicals are formed in the body cells that break down DNA and cell membrane.
  • Alveoli Collapse: Alveoli (air sacs) have a thin epithelial layer known as a respiratory membrane. Oxidative damage weakens this layer, impairing the gaseous exchange (because the air sacs fail to inflate correctly).
  • Retinal Detachment: Excess oxygen can cause retinopathy and retinal detachment. It may also end in permanent blindness.
  • Convulsions: Oxygen toxicity directly impacts the central nervous system (CNS), resulting in seizures.

Even when treated promptly, severe lung damage reversal may take weeks. If left unattended, oxygen toxicity may also lead to death. Therefore, it is crucial to adequately set up the oxygen therapy concentrator.

What Are The Symptoms Of Not Getting Enough Oxygen?

Hypoxia or low oxygen levels (pulse ox below 95%) are characterized by bluish skin discoloration, wheezing, profuse sweating, shortness of breath, fast heart rate, etc.

Low oxygen levels in the body are medically termed hypoxia or hypoxemia.


The following things can trigger hypoxemia:

  • Lung diseases like chronic obstructive pulmonary disease (COPD), emphysema, bronchitis, pulmonary edema, etc.
  • Acute asthma attacks
  • Severe coughing
  • Cardiovascular disorders such as atherosclerosis, pulmonary arterial hypertension, heart failure, etc.
  • Anemia (low hemoglobin levels)
  • Certain opioid drugs like morphine, fentanyl, heroin, etc.
  • Poisoning


If you begin experiencing hypoxia, immediately call the local hospital emergency service. Doctors first aim to restore your oxygen levels for hypoxia via concentrators, inhalers, or steroid drugs.

Once you attain stability, they may run some tests to find the exact cause of the situation.

In case the condition worsens, you may be transferred to ICU to receive high-flow oxygen therapy via advanced high-pressure equipment.

If immediate medical help is unavailable, you may try taking slow, deep breaths to relieve the symptoms. Standing or sitting straight reduces pressure on the lungs and may also help.


Here are a few tips to prevent hypoxia:

  • Avoid smoking as tobacco smoke is the primary trigger for various respiratory issues like asthma, bronchitis, etc.
  • Use air purifiers to maintain a healthy environment. Units with HEPA and activated charcoal filters are the best as they remove 99.97% of microscopic particulate matter, germs, gases, and VOCs from the air.
  • Get regular medical check-ups. Routine physical examinations reveal essential medical information. They are recommended at least once every three years for healthy individuals under 30. Whereas, for adults over 50 years, once a year is advised.
  • Maintaining a healthy lifestyle, eating low-grease, nutritious food, and exercising daily can significantly reduce your chances of developing respiratory and heart conditions.

Plentiful Air also has more information on how to clean and maintain your oxygen concentrator available here.

What Are The Symptoms Of Getting Too Much Oxygen?

Too much oxygen (higher than 110 mmHg) is called oxygen toxicity. It manifests as coughing, mild throat irritation, chest pain, labored breathing, blurred vision, headache, and nausea.

How Can I Monitor My Oxygen Saturation At Home?

You can use a finger pulse oximeter to monitor oxygen levels at home. The SpO2 reading on the device indicates oxygen concentration in the body.

A pulse oximeter is a device that detects and determines the percentage of oxygen in the red blood cells. Before using an oximeter, make sure to /that:

  • Your fingers are warm
  • There’s no nail polish
  • Use index or middle finger
  • Sit still for 5 minutes before the test
  • Keep your finger on the oximeter still until the reading appears stable.

If you’re looking for pulse oximeters, here are four of the best devices you can consider buying:

Innovo Premium iP900BP Fingertip Pulse Oximeter

The first product is Innovo Premium iP900BP Fingertip Pulse Oximeter. It detects and displays highly accurate and precise readings of your blood oxygen saturation level, pulse rate, and pulse strength within seconds.

Additional features include plethysmograph (checks for blood clots) and perfusion index (ratio of pulsatile blood flow to static blood flow that indicates the strength of blood flow to the fingers) measurement.

For user convenience, it has an adjustable display that can be rotated in many ways for a comfortable and clear view. Furthermore, you also get to choose from six clear layouts for your display.

The package comes with two AAA batteries that keep the device running for a long time. A lanyard is also present to further assist the user.

Accurate Pro Series 500DL Fingertip Pulse Oximeter

Accurate Pro Series 500DL determines your oxygen saturation levels, pulse rate, and pulse strength within 10 seconds, which is then displayed on a large, clear LED display. Manufacturers claim this is the only LED pulse oximeter that can read up to 100% of SpO2.

Its finger chamber has a SMART Spring System that adjusts to various finger sizes. Therefore, the device is reliable for adults and children alike.

It has two AAA batteries for 40 hours of battery life, a silicon cover, and a lanyard that keeps the device in good shape and protects it from environmental contaminants. The 12-month warranty makes it a great choice as an inexpensive yet highly-accurate pulse oximeter.

Deluxe SM-110 Two Way Display Finger Pulse Oximeter

The following product is Santamedical’s Deluxe SM-110 Two Way Display Finger Pulse Oximeter. It is clinically proven to provide accurate oxygen saturation level, pulse rate, and pulse strength within 8 to 10 seconds.

The display screen gives you a red LED view, while the two-way feature enables you to read in two different directions.

It has a latex-free silicone material that accommodates several sizes of fingers. In addition, it’s lightweight and compact, which makes it easy for the user to carry it around. With all the amazing features and 1-year warranty, this is a great device to invest in, especially for sports and aviation use.

Metene Pulse Oximeter

Next up, we have the Metene Pulse Oximeter. It is an accurate and reliable device that employs a highly advanced MCU chip and sensor to collect blood oxygen signals photo electrically. This implies that within 5 to 10 seconds, this device can display precise and dependable oxygen saturation, level, pulse rate, and intensity.

It adjusts to a wide range of finger sizes (8 to 25.44 mm), making it suitable for use by adults and children alike. The high-quality acrylic panel and compact construct add to the portability and customer appeal.

The package is priced reasonably, with a detachable lanyard, a user manual, and two AAA batteries. The ease of use with the one-button operation, automatic shut-down feature (after 8 seconds of no operation), and other characteristics make this device worth considering.

How Many Hours Do Home Oxygen Concentrators Last?

Oxygen concentrators take up the fresh air and generate pure oxygen from it. Therefore, they do not require a refill and can work optimally if the air supply is adequate. Depending upon the quality and maintenance, concentrators usually last about 1500 to 2000 hours.

Does Using Oxygen Make Your Lungs Weaker?

Supplemental oxygen (when used at a healthy concentration) does not adversely affect the lungs. Oxygen therapy eases respiratory distress and associated symptoms. While it does not cure lung disease, it does improve its functions to an extent.

Best Oxygen Concentrators

Buying a concentrator that works well, is crucial to ensure a healthy and effective oxygen therapy. Following points should be considered when buying a concentrator:

  • Flow rate
  • Oxygen concentration
  • Power consumption
  • Portability
  • Noise level
  • Warranty
  • Maintenance charges

Based on these factors, here are three of the best oxygen concentrators you can consider buying:

Inogen One G5 Oxygen Concentrator

The first product is Inogen One G5 Oxygen Concentrator. It is a portable oxygen tank that comes with a slim carry case that is perfectly suitable for effective at-home or mobile oxygen therapies.

The package includes an external battery charger that offers fast charging for the Inogen One G5 battery. It also ensures energy conservation via an LED charge indication system.

This unit can be run 24 hours a day and has six different flow settings. It has a tankless system and can be connected to your mobile using Bluetooth to provide you with important information including portable oxygen concentrator tracking and diagnosis.

Philips Everflo Oxygen Concentrator

Philips Everflo Oxygen Concentrator is one of the devices at the top of the game. It is lightweight and low maintenance, which promises a great and hassle-free user experience. The three-year warranty is another factor that ensures this device is a worthy investment.

One of the best features of this concentrator is that it comes with a humidifier bottle that dampens the oxygen to prevent dryness of the mouth and subsequent discomfort. Other than that, a nasal cannula, filter set, and power cable are also included in the package.

Invacare Platinum Mobile Oxygen Concentrator

Next up, we have an easy-to-use Invacare Platinum Mobile Oxygen Concentrator, which can be rented at It comes with hot swap top-load batteries that allow you to switch batteries without removing the unit from the bag.

One of the best features of this device is the HEPA filtration system. HEPA, or High-Efficiency Particulate Filter, is one of the best and most advanced filters. It has microscopic pores that remove airborne contaminants like dust, debris, pollen, allergens, and microbes (bacteria, mold, viruses), measuring 0.3 microns or more; thus, purifying the air by over 99%.

The HEPA filter in Invacare Platinum Mobile Oxygen Concentrator is located on the unit’s exterior surface. It functions as a great 2-in-1 concentrator and air purifier device that keeps the air clean and safe to breathe.

Russell Singleton

Russell holds a Bachelor of Science (Environmental and Marine Geoscience) with Class I Honors. He is currently completing his doctorate in science and is passionate about all earth processes, especially isotope geochemistry and paleohydrology.

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