Hyperbaric Chambers

Oxygen tank

Many respiratory diseases require special equipment for treatment and therapy. With everything from asthma inhalers to oxygen concentrators, the list of equipment can be intimidating. We'll help you navigate through it.

  • Equipment Info
  • Oxygen Delivery
  • History and Statistics
  • Glossary


Hyperbaric medicine, also known as hyperbaric oxygen therapy (HBOT), is the medical use of oxygen at a level higher than atmospheric pressure. The equipment required consists of a pressure chamber, which may be of rigid or flexible construction, and a means of delivering 100 percent oxygen. Operation is performed to a predetermined schedule by trained personnel who monitor the patient and may adjust the schedule as required. HBOT found early use in the treatment of decompression sickness. But it has also shown great effectiveness in treating conditions such as gas gangrene and carbon monoxide poisoning. More recent research has examined the possibility that it may also have value for other conditions such as cerebral palsy and multiple sclerosis, but no significant evidence has been found.

The human body needs oxygen to survive; this is certainly no secret. Unfortunately, some people’s bodies lack the ability to take in the oxygen they require. This issue can be seriously debilitating, if not life-threatening. Thankfully, advances in medical technology have provided people a number of oxygen therapy systems to meet a variety of needs.

Choosing an oxygen therapy system may seem overwhelming at first, but picking the right one can make life exponentially easier.

The three main types of supplemental oxygen therapy delivery systems include:

  • Compressed Oxygen Cylinders
  • Oxygen Concentrators
  • Liquid Oxygen
Feature comparison of supplemental oxygen therapy delivery systems Compressed
Oxygen Cylinder
Power None required Standard home outlet Rechargeable battery Standard home outlet for reservoir
Refill Process Home delivery available None required None required Transfer from home reservoir
Air Delivery 100% oxygen 95% oxygen, 5% ambient 95% oxygen, 5% ambient 100% oxygen
Size Bulky and heavy "Dorm fridge" size Handbag to rolling suitcase size Handbag to backpack size
Maintenance Check vavles periodically Replace filter periodically Replace filter periodically Check valves periodically
Flow Rate Adjustment Analog via valve gauge Digital setting Digital setting Analog via valve
Oxygen Capacity Dependent on tank size Infinite Infinite 0.7 - 1.0 liters for portable tank
Safety Considerations Damage to valve or tank can cause explosion None None Ports can cause frost burn if not handled correctly
Portability Smaller capacity tanks available On wheels for moving from room to room Shoulder strap or wheels Mobile tanks - yes, reservoir - no
Allowed on airplanes Most meet FAA requirements
Intermittent Flow Varies
Continuous Flow Varies Varies

Compressed Oxygen Cylinders:

Compressed oxygen cylinders are perhaps the most well-known, and possibly the most iconic type of oxygen delivery system. They are the most basic and simple form of oxygen therapy, and also one of the most reliable. The cylinders consist of a tank filled with compressed oxygen, a valve that is manipulated to deliver a specific amount of oxygen and a plastic delivery tube. Tanks for home use are generally very large and bulky, rendering their mobility challenging. The tanks are supplied and home-delivered by a medical supply company. The tanks then need to be secured in a sturdy manner, in order to ensure the tanks’ safety. Smaller portable tanks are available for mobile use.

Compressed oxygen is placed inside of steel tanks which are built to withstand the internal pressure of the compressed gas. A flow regulator allows oxygen to be delivered to a person, at a lower pressure, while still maintaining the pressure inside the tank. Oxygen is a volatile gas and under pressure, it can become dangerous. The tanks are constructed to keep the oxygen from combusting, but additional care should be taken to secure the tanks in an upright position, at relatively low temperatures, and away from any potential falling objects.

While the bulky size of the larger tanks renders them impractical for portable use, it makes them highly effective for home-use. A key is used to open and close the tank’s valve. The tanks carry enough oxygen to last a considerable amount of time, depending on the relative flow rate being utilized. Once the tank approaches empty they must be replaced immediately, as to prevent a life-threatening situation for someone that is oxygen dependent. It is wise to keep a small replacement cylinder on hand just in case the large oxygen cylinder runs low without being noticed. Because these tanks operate on their own, they do not need an outside source of power, such as a home’s electrical outlet or a battery.

Oxygen Concentrators:

Oxygen concentrators take in the ambient air from the environment, isolate the oxygen, and deliver a concentrated dose of oxygen. They consist of an air compressor and zeolite-filled container. The compressor brings the ambient air into the machine. Ambient air is made up of roughly 78% nitrogen and 21% oxygen. The zeolite minerals absorb the nitrogen to separate it from the oxygen, resulting in a concentrated dose of up to 95% pure oxygen. Oxygen concentrators come in many different sizes, and can fit almost any need, whether that need is at home or on-the-go. Home oxygen concentrators (HOCs) tend to be larger than their more portable counterparts, but they are more efficient in both their oxygen delivery and their energy use. They plug right into a household electrical outlet, and often times come with a set of wheels, allowing them to be transported from one room to another, if needed.

HOCs output a continuous flow of oxygen. A continuous flow of oxygen provides consistent, high levels of oxygen to keep the body as healthy as possible. HOCs feature oxygen outputs ranging anywhere from 2 Liters per Minute (LPM) up to 10 LPM.

Portable oxygen concentrators (POCs) differ from their home counterparts in a number of ways. First, they are smaller and lighter. This, of course, allows them to be easily transported anywhere their user needs to go. Since a wall outlet is impractical for a portable device, POCs run on a battery. Battery life varies from model to model, so it is important to know how long the battery will last, and plan trips accordingly. The last thing anyone wants is to run out of oxygen away from home.

Another major difference between portable and home oxygen concentrators is the way the oxygen is delivered. Instead of being a continuous flow, portable concentrators deliver a pulsing, otherwise referred to as intermittent, flow of oxygen. This results in lower doses of oxygen, but allows for a longer battery life, as well as a smaller, lighter design.

Liquid Oxygen:

In extremely cold temperatures (-300°F) oxygen changes from a gas state to a liquid state. In a liquid state, the same amount of oxygen takes up about one tenth of the volume of oxygen than does a gaseous state. Because of the lower volume, large amounts of liquid oxygen can be stored using much less pressure than compressed oxygen in the gaseous phase. Liquid oxygen can be stored and used for oxygen therapy.

The liquid oxygen is kept in a large reservoir tank. An empty portable unit can be filled from the reservoir tank and used for therapy. In some cases, supply tubes can be connected directly into the reservoir, so that the reservoir tank itself can be applied for home use.

Liquid oxygen is kept under far less pressure than compressed oxygen, making it safer and less volatile. The down-side is that the ports are exceptionally cold, and can burn the skin quite badly if touched. Much care is needed when filling a portable unit directly from a liquid oxygen source. When the unit is turned on, the liquid warms, changing phases from liquid to gas, and is safely supplied to it’s user at room temperature.

Liquid oxygen units come in sizes ranging from 0.7 liters to more than a full liter, and only weigh between 6 and 9 pounds. The oxygen is delivered at a continuous flow, and depending on the unit, oxygen output is at either 0-6 liters per minute (LPM), or a high flow output of 15 LPM. Because of their small size and relative light weight, the portable units can be transported easily with a shoulder strap or a cart. The oxygen will remain in liquid form in the reservoir tank, but once the portable tank is filled, it will begin to empty. With these systems, it is important to only fill the portable tanks immediately before use, to avoid unnecessarily wasting the oxygen.

Choosing the Appropriate Oxygen Therapy System:

With dozens of models to choose from, picking an appropriate product seems like a daunting task. To make the decision easier, it is important to narrow the search by determining which features are most important to the user’s needs. Everyone’s needs are different. There is no single, ‘best’ model. There is a ‘right’ model, but it varies from one person to the next.

The most important factor is an understanding of the daily oxygen requirement of the user. If large amounts of oxygen are needed, a high-output machine is necessary. If there is any question about how much oxygen is needed, or if a certain model will provide the proper dosage, consult a doctor before purchasing.

Another important factor is where the oxygen will be used. If used in the home, it is important to make sure a clear space is available in the room that the oxygen will most frequently be used. If using an HOC, make sure that an outlet is available where the HOC will be placed. If a portable oxygen system is desired, it is important to consider how long the oxygen will be needed. Portable systems can only supply oxygen for a limited time. Be sure to find an oxygen therapy system that will not run out before the trip is over.

It’s important to make sure that the system is mobile, in the event this option is required. Portable systems need to be carried and moved for longer periods of time, but home systems should be easy enough to move from one room to the next when necessary.

It’s important to make sure that the system is mobile, in the event this option is required. Portable systems need to be carried and moved for longer periods of time, but home systems should be easy enough to move from one room to the next when necessary.

It’s also important that the user knows how their oxygen therapy functions. Some devices have several settings, which can sometimes be misleading. Not knowing what each setting means can result in an incorrect dose of oxygen being delivered. This can be both dangerous and wasteful, so be sure you receive proper training on how to use the system, before operating it alone.


Once a person’s specific needs are analyzed, the search can be narrowed to a select few products, leaving them with a much easier decision. Choosing the oxygen therapy system that fits best will assure that they are satisfied with their purchase. Purchasing the correct system, for one’s personal oxygen needs, will allow the user a higher quality of life while also enabling them to stay within their financial means.

How Oxygen Concentrators Work

A patient on oxygen therapy receives air with a higher concentration of oxygen than the ambient air. As opposed to a compressed oxygen tank, which delivers some amount of pure oxygen, a concentrator removes other components from the air, achieving the same effect more safely and at a lower cost. It’s a pretty straightforward idea, but how is it accomplished?

How oxygen concentrators work infographic


APRAir purifying respirator
Blood gas analyzera machine that measures oxygen, carbon dioxide, and pH levels in a blood sample. These extremely important measurements are required to care for patients in the hospital, especially sicker patients with lung & heart disorders.
Body plethysmographa machine used in lung (pulmonary) function labs to measure lung function in order to diagnose and quantify lung disorders.
Bronchoscopea fiber-optic scope that is inserted into the patient's airways (bronchi) to visualize and obtain samples for diagnosing lung disorders and sometimes used for removing obstructions in the airways. This is one of the more common tools used by specialists in helping diagnose lung diseases.
CABClean Air Box compressed air systems for Grade D air
Cardio respiratory monitora monitor that measures and continuously displays heart rate & rhythm, blood pressure, and respiratory rate. These are important "vital signs" that are monitored in acutely ill patients
EEBAEmergency Escape Breathing Apparatus
Esophagoscopesame as a bronchoscope but is used to assess the esophagus rather than the bronchi.
IDLHImmediately Dangerous to Life and Health
Laryngoscopea device that is used in the procedure of placing an artificial airway (endotracheal tube) into a patient's trachea in order to maintain their airway open. Used for unconscious patients, patients that can no longer breathe on their own, etc.
Nebulizera device that either adds humidity to dry medical gas that a patient is breathing or provides a mist of medication that a patient can breathe in.
Oxygen analyzera device that measures the oxygen levels (concentration) in a breathing system. Delivered oxygen levels need to be increased in order to provide enough oxygen to patients with lung or heart disorders.
Oxygen concentratora machine that takes in atmospheric air (with 21% oxygen) and concentrates the outgoing gas to 100% oxygen. Used to provide patients with supplemental oxygen (higher oxygen levels than room air).
Oxygen monitora machine that provides continuous oxygen monitoring for hospital and home ventilators, and NICU and aesthesia delivery equipment.
PAPRPowered Air Purifying Respirators that use a blower that draws air through cartridges or filters
PDARPressure Demand Airline Respirator
Peak flow metera device that helps patients monitor their asthma easily.
Pulmonary function systema system that tests people's breathing in order to diagnose lung disorders
Pulse oximetera device that measures oxygen saturation and assesses pulse rate
Respiratorsee ventilator
SARSupplied Air Respirator
SCBASelf Contained Breathing Apparatus
Spirometera device that tests lung function; is one component of a complete pulmonary function machine
Suction regulatora device that controls the amount of suction (vacuum) that helps in removing secretions from a patient's airways, lungs, thoracic cavity, stomach, or other body cavities
Ventilatora machine that assists or provides all of the breathing for patients who cannot breathe on their own (also known as a respirator)