How Much Oxygen Does a Portable Concentrator Produce

How Much Oxygen Does a Portable Concentrator Produce

Does your difficulty in breathing limit your day to day life up to the point that you require the use of Portable Oxygen Concentrators? How exactly does a simple device such as oxygen Concentrators help you to breathe in enough pure oxygen? 

Read through this article as we go into a deep dive on the topic of Portable Oxygen Concentrators and how much oxygen they produce.

How Much Oxygen Does a Portable Concentrator Produce?

Oxygen concentrators, removes nitrogen from the air and concentrates the amount of oxygen we breathe up to 90 to 95 percent. The amount of oxygen it produces depends on its size, the inward flow of oxygen to the machine and the pattern of breathing.

Generally, portable concentrators may deliver up to 0.5-5 liters per minute of oxygen, while some may generate as much as 10 liters of pure oxygen gas per minute which is independent of the pattern of breathing. Since different models offer different rates of oxygen flow, one of the major considerations in purchasing portable oxygen concentrators should be the flow rate of oxygen the device could deliver.

Elderly man wearing a nasal cannula attached to a portable oxygen concentrator

Portable Oxygen Concentrators & Supplemental Oxygen

Supplemental oxygen is used by more than 1.5 million adults in the United States to improve their quality of life and prolong their survival due to a range of respiratory illnesses. Supplemental oxygen therapy is a form of therapy which uses equipment to supply the required amount of oxygen.

This can be provided for you conveniently at home or in hospitals through delivery systems such as: oxygen cylinders, liquid oxygen or oxygen concentrators. Each has its own advantages and disadvantages in terms of liter flow, equipment cost and portability.

Ideal supplemental oxygen therapy is patient-specific, administered by a qualified physician, and involves a tailored prescription and therapeutic education program. It offers oxygen systems that are safe, promote mobility, and treat hypoxemia or lack of oxygen in the blood.

Patients and physicians in the United States have recently reported an increase in the number of difficulties using home oxygen. Oxygen users have major functional, mechanical, and budgetary issues, as well as a lack of information about their oxygen equipment, all of which have a negative influence on their quality of life.

Some of the factors that you should consider in choosing the system best suitable for you are the following: the amount of oxygen you need, the size and layout of your home environment, and also your preferences based on your lifestyle or activities. The main goal of supplemental oxygen therapy is to enable you to have ease of breathing and allow you to continue to keep enjoying your usual activities.

So what is the difference between the following supplemental oxygen systems? All deliver oxygen directly to you through nasal cannula or oxygen masks, but they differ mainly in the way oxygen is provided. 

  • Oxygen tanks and oxygen cylinders limited stored compressed oxygen gas. 
  • Oxygen concentrators on the other hand, do not deliver stored, but generate an infinite supply of oxygen depending on the amount of air in your surroundings and its battery life. 

Oxygen cylinders

 three oxygen cylinders with one oxygen mask

Oxygen cylinders come in a variety of sizes, which affect the amount of oxygen they can hold. There are three ways to distribute portable oxygen using compressed oxygen cylinders: a portable cylinder, a lightweight cylinder, and a home fill cylinder.

A compressed oxygen cylinder has a small capacity: for example, with a 200 bar filling pressure and 400 L of oxygen. In which, it enables you to have an oxygen supply lasting about 2.5 hours, depending on the flow rate.

As mentioned, cylinders offer a limited supply of oxygen, which means, to renew the oxygen supply, these cylinders must be replaced or refilled on a regular basis. The gas provider replaces the cylinders, and the frequency of deliveries is determined by the size of the cylinder and the amount of oxygen consumed. Also compared to other devices, the majority of cylinders are huge, bulky, and are less convenient to carry without equipment such as trolleys and wheeled carts.

Recent technology has made alternative devices to cylinders which include the much smaller devices oxygen concentrators. These devices can provide oxygen for up to several hours, depending on patient usage. From the following systems, concentrators are the only ones that are electrically powered. These must be plugged in or attached with a charged battery to be able to generate oxygen.

Aside from power usage, concentrators are made portable and are well-suited for smaller spaces and for transport. Oxygen Concentrator works by concentrating the oxygen we breathe and is a safe way to get oxygen-rich air. 

Oxygen Concentrators

Oxygen concentrators (also known as oxygen generators) are machines that draw in surrounding air through a series of filters to remove dust, bacteria, and other contaminants.

The device drives air into one of two cylinders containing a molecular sieve bed or a semi-permeable membrane, where nitrogen is absorbed, thus leaving behind concentrated oxygen and a small percentage of other gasses in room air.

Meanwhile, in the other cylinder, nitrogen is absorbed and released out into the atmosphere. Both processes of drawing in and drawing out air occur at the same time in the two cylinders. Lastly, in the second step, the function of the two cylinders are reversed which allows for a continuous flow of oxygen delivery. 

In oxygen concentrators, there are two forms of oxygen delivery: continuous flow dose delivery and pulse mode delivery.

Pulse mode delivery offers a pulsed "bolus" of oxygen when the user takes a breath, whereas continuous flow dose delivery provides a consistent, steady, and reliable oxygen flow based on the preset number in liters per minute. Individual flow settings should be changed first. 

High-quality concentrators have been clinically proven to supply the essential oxygen for most ambulatory patients during all phases of daily activity and sleep, and can be used 24 hours a day, seven days a week. Pulse-dose technology is used in most portable concentrators. However, concentrators have a disadvantage in that they can only deliver 5 to 10 liters of oxygen per minute. They are therefore unsuitable for serious patients requiring more than 40 to 45 liters of pure oxygen per minute.

There are two types of oxygen concentrators: the stationary and portable concentrator. Stationary concentrators provide an uninterrupted oxygen supply and weigh around 10 kg on average. They come with various ergonomic handles that help you lift or roll the device.

New small concentrators have recently hit the market, allowing stationary concentrators to be more transportable than ever before. The concentrator connects to your home's main power source and consumes 300 W or less each hour. This is equivalent to the consumption of four light bulbs. In the event of a power outage, a backup compressed gas cylinder is occasionally provided.

Portable Oxygen Concentrators

Portable oxygen concentrators are the recently developed oxygen devices for long-term oxygen therapy users who prefer a small, lightweight, and portable oxygen solution in a small and portable machine.

Compared to stationary concentrators, portable oxygen concentrators are intended for on-the-go. They are smaller, lighter, and operate on battery power. Most of them are FAA-approved, which means you can take them on a plane with you. Weight, size, oxygen flow settings, liter per minute range, and battery life, among other features, differ among portable concentrators. 

Considerations for considering either stationary and portable concentrators include:

Stationary oxygen concentrators produce more oxygen and are less expensive while portable oxygen concentrators have a reduced size and weight, as well as more power source flexibility. 

The use of PDOCD (pulsed-dose oxygen-conserving device) has become widespread  as a method for lowering the cost and inconvenience of portable oxygen supply. Despite the ubiquitous usage of PDOCDs in awake and ambulating patients, few researchers have looked into how they are used while sleeping. 

In the clinical study by Chatburn, Lewarski and McCoy, nocturnal oxygenation was measured in 10 home-oxygen patients who were using various continuous-flow oxygen systems and prescriptions. For one night, each patient's continuous-flow system was replaced with a PDOCD (Inogen One, Inogen, Goleta, California) with nasal cannula. Nine out of ten patients with the Inogen One PDOCD had nocturnal SpO2 and heart rates that were clinically similar to their continuous-flow baseline readings. It was concluded that the selected patients were able to maintain adequate SpO2 during sleep.

From the following discussion, if the ability to continue daily living without limited mobility is your major concern especially for those who require an on-the-go source of oxygen, also taking into consideration the prevention of  continuous tank replacement, then Portable Oxygen Concentrators may be the system for you.

Before purchasing a portable oxygen concentrator, check with a physician to determine the amount of oxygen per liter that you may require. You should also consider the following factors: 

  • Checking the flow rate capabilities of an oxygen concentrator is one of the most crucial elements to consider when purchasing one. The flow rate refers to how quickly oxygen may go from the oxygen concentrator to the patient in liters per minute (LPM).
  • The oxygen concentrator's capacity must be greater than your requirement. If you need a 3.5 LPM oxygen concentrator, for example, you should get a 5 LPM concentrator. In the same way, if you need a 5 LPM concentrator, you should get an 8 LPM machine. 
  • Check the oxygen concentrator's sieve beds and filters. The number of sieves/filters in a concentrator determines the oxygen quality output. The oxygen produced by the concentrator must be 90-95 percent pure.
  • Lastly, overall power consumption, mobility, noise levels, and warranty are some of the key considerations to consider in choosing an oxygen concentrator appropriate for you.

5 Factors That Affect Your Body’s Oxygen Needs

Aside from the onset of respiratory diseases which confer difficulty in breathing, there are factors that influence our subsequent need for oxygen which include the following:

Blood flow

automatic sphygmomanometer blood pressure apparatus

Your body's supply of oxygen depends directly on blood flow. The cardiovascular system comprising your heart, blood vessels and blood controls blood flow to individual organs. Once you breathe, oxygen diffuses through your capillaries and is carried by hemoglobin or your red blood cells. The flow of blood then establishes which tissue needs oxygenation. 

Diseases of the heart and blood vessels limit blood flow, thus limit the delivery of oxygen to your tissues.

Amount of red blood cells

It was mentioned that your hemoglobin or red blood cells (RBC) are the ones that carry or bind to oxygen to enable its flow in the blood. RBCs have four binding sites which allows it to carry four oxygen molecules at once. Once all of its four oxygen-binding sites are occupied with oxygen, it is then said to be saturated and is now called oxyhemoglobin. Oxyhemoglobin is pumped together with blood and delivered to tissues. 

Diseases such as anemia, indicating a significantly lower amount of red blood cells, also have limited oxygenation of tissues. To compensate for the lack of delivery of oxygen, the rate of pumping of blood increases in anemic patients.


old woman smiling while wearing nasal cannula attached to portable oxygen concentrator

In early to middle adulthood, respiratory function begins to deteriorate. As you age, your vital lung capacity and respiratory muscle power have deteriorated, leaving you vulnerable to low oxygen levels due to a decrease in labor of breathing.


elderly women working out

Oxygen saturation during exercise drops from the normal 95-100% due to the increased oxygen requirement of working muscles. As you exercise and your muscles work harder, the synthesis of metabolites such as carbon dioxide and the demand for oxygen both rise. To meet the increased demand, your breathing rate must increase from about 15 times per minute (12 liters of air) at rest to roughly 40–60 times per minute (100 liters of air) during exercise. Your heart rate increases as well, allowing more oxygen to reach the muscles, allowing them to continue to move.


hand holding a thermometer

Increased blood temperature in fever reduces the affinity of oxygen for hemoglobin. This means that there is a decrease in the binding capacity of oxygen to hemoglobin thus decreasing the oxygen saturation of blood.

How to Know How Much Oxygen You Need?

Normal blood oxygen level falls between 95-100%. It means that you need a minimum amount of 95 percent of oxygen circulating in your blood. 

Tests may be done to help you identify the amount of oxygen you need which includes the use of pulse oximetry or arterial blood gas analysis.

Pulse Oximetry

index finger inside a pulse oximeter

Pulse oximetry is a test which offers an indirect measurement of arterial oxygenation (SaO2). It is more commonly used using a device called a pulse oximeter that is clipped to your finger.

It shines a light through your finger which is absorbed by the hemoglobin in your red blood cells. The pulse oximeter then calculates the amount of light absorbed and measures the oxygen saturation of your hemoglobin. Pulse oximetry is a non-invasive and quick way to determine SaO2, especially when the SaO2 level is above 75%. 

Arterial Blood Gas

arterial blood gas test request

Meanwhile, arterial blood gas (ABG) analysis provides a direct measurement of the arterial partial pressure of oxygen (PaO2) and SaO2, as well as other critical indicators for determining ventilation and acid-base status.

ABG analysis, on the other hand, necessitates additional time and money, as well as an arterial puncture. Blood is drawn from your artery, specifically in your wrist and is then sent through an analyzer.

This measures the amount of oxygen gas dissolved in the blood which is called the arterial oxygen partial pressure (PaO2). Pressure is expressed in millimeter mercury and normal levels of arterial oxygen pressure fall between 80-100 mmHg.

When your blood oxygen level falls below 91% or 60 mmHg, this may indicate and call for the use of supplemental oxygen. 

FAQs About Portable Oxygen Concentrator

Some frequently asked questions and inquiries about portable oxygen concentrator are the following:

Does an oxygen concentrator deliver 100% oxygen?

No. Oxygen concentrators deliver up to only 95% of pure oxygen. Breathing this amount of oxygen is generally not recommended as acute oxygen poisoning can occur when you breathe 100 percent oxygen at normal pressure. This can induce a variety of symptoms, including pulmonary edema, hyperventilation, and laborious breathing. Lastly, it may eventually lead to atelectasis or the collapse of the alveoli.

What percentage of oxygen does an oxygen concentrator deliver?

An oxygen concentrator draws in surrounding air consisting of 21 percent oxygen and 78 percent nitrogen. It concentrates oxygen and is capable of delivering 90-95% percent of this gas directly to the nasal cannula or oxygen mask.

Do portable oxygen concentrators deliver oxygen only?

Yes. They deliver 95% pure oxygen directly to the patient. However, this still depends on the number of sieves or filters employed in the concentrator. The number of sieves determines the quality of the oxygen produced. As such, there is a need for constant device checking and maintenance which includes replacement of sieve beds.

How Much Oxygen Does a Portable Oxygen Concentrator Produce - Sprylyfe infographic

Get Your Oxygen Needs with a Portable Concentrator Now! 

Breathing should not be difficult and limit your day to day life. Through technology, we have made breathing enough oxygen easier to those who need it most. Continuous development opened the doors to oxygen devices that deliver in pure oxygen without the expense of limiting your previous activities. 

You have the power to decide which system works for you and now have more options to choose from. As such, upon reading the article, we hope you have learned a lot and gained sufficient ideas about the amount of oxygen that can be generated by portable oxygen concentrators. May this help you in your decision of which system to use. 

If you’re not sure what portable oxygen concentrator is best for you, check out our handy guides:

If you’re ready to buy, check our shop at Sprylyfe to find affordable portable oxygen concentrator machines for sale that suit your lifestyle and oxygen needs. You can also call our respiratory specialists at (800) 314-8225 if you need assistance.
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