Oxygen concentrator

Oxygen concentrator
A home oxygen concentrator in situ in an emphysema patient's house. The model shown is the DeVILBISS LT 4000.
An Invacare Perfecto 2 oxygen concentrator

An oxygen concentrator is a device providing oxygen therapy to a patient at minimally to substantially higher concentrations than available in ambient air. They are used as a safer, less expensive, and more convenient alternative to tanks of compressed oxygen. Common models retail at around US$800. Leasing arrangements may be available through various medical-supply companies and/or insurance agencies.

Oxygen concentrators are also used to provide an economical source of oxygen in industrial processes.


How they work

It has two cylinders filled with zeolite which selectively adsorbs the nitrogen in the air. In each cycle, air flows through one cylinder at a pressure of around 20 psig, where psig indicates the gauge pressure (138 kPa, or 1.36 atmospheres) where the nitrogen molecules are captured by the zeolite, while the other cylinder is vented off to ambient atmospheric pressure allowing the captured nitrogen to dissipate.

Typical units have cycles of around 20 seconds, and allow for a continuous supply of oxygen at a flow rate of up to approximately five liters per minute (LPM) at concentrations anywhere from 25% to 95%. This process is called pressure swing adsorption (PSA).[1] Since 1999, concentrators providing up to 10 LPM have been available for high flow patients, in sizes not much larger or heavier than 5 LPM concentrators.

Portable oxygen concentrators

Since 2000, a number of manufacturers have introduced portable oxygen concentrators. Typically, these produce less than one liter per minute (LPM) of oxygen and use some version of pulse flow or demand flow to deliver oxygen only when the patient is inhaling. However, there are few portable oxygen concentrators that produce 3 LPM of continuous-flow oxygen. Also providing pulse flow available to either provide higher flows or reduce power consumption. These portable concentrators typically plug into a wall outlet like the larger, heavier stationary concentrators. [2]

Portable oxygen concentrators usually can also be plugged into a vehicle DC adapter, and most have the ability to run from battery power as well, either for ambulatory use or for use away from power or for airplane travel. The FAA has approved portable oxygen concentrators for use on commercial airlines, although it is necessary to check in advance whether a particular brand or model is permitted on a particular airline.

Historically, demand or pulse flow concentrators have not been used for nocturnal use—sleeping. If the nasal cannula moves such that the concentrator is not able to detect when the patient is inhaling, it is unable to deliver the pulse while the patient is inhaling.

Military uses

Combat aircraft use molecular sieve oxygen concentrators (MSOC) to supply the pilot with oxygen at high altitudes.

Oxygen concentrators are also used by the US military in the conflicts in Iraq and Afghanistan as part of the equipment complement of forward surgical teams.


In both clinical and emergency-care situations, oxygen concentrators have the advantage of not being as dangerous as oxygen cylinders, which can, if ruptured or leaking, greatly increase the combustion rate of a fire. As such, oxygen concentrators are particularly advantageous in military or disaster situations, where oxygen tanks may be dangerous or infeasible.

Oxygen concentrators are considered sufficiently foolproof to be leased to individual patients as a prescription item for use in their homes. Typically they are used as an adjunct to CPAP treatment of severe sleep apnea. There also are other medical uses for oxygen concentrators, including emphysema and other respiratory diseases.

Used and refurbished units should be purchased through a reputable dealer. Temperamental units are worthless to the medical community since an individual's health frequently relies on the constant extended operation of the unit. However, such units are valuable to metal and glasswork hobbyists. Because oxygen is a "permanent gas" (cannot be liquefied at any pressure at room temperature), it expensive to obtain in bottled form. Medical oxygen concentrators or dedicated industrial (non-medical) oxygen concentrators can be made to operate a small oxy-acetylene torch quite easily, if only at lower pressures.[3]

Industrial oxygen concentrators

Industrial processes may use much higher pressures and flows than medical units. To meet that need, another process, called vacuum swing adsorption (VSA), has been developed by Air Products. It uses a single low pressure blower and a valve which reverses the flow through the blower so that the regeneration phase occurs under a vacuum. Generators using this process are being marketed to the aquaculture industry.[4] Industrial oxygen concentrators are often available in a much wider range of capacities than medical concentrators.

Industrial units are sometimes referred to as oxygen generators within the oxygen and ozone industries to disambiguate from medical oxygen concentrators. The distinction is used in an attempt to clarify that industrial oxygen concentrators that are not FDA-approved medical devices are not suitable for use as bedside medical concentrators. However, applying the oxygen generator nomenclature can lead to confusion. The term, oxygen generator, is a misnomer in that oxygen is not generated as it is with a chemical oxygen generator, but rather is concentrated from the air. The use of the oxygen generator terminology can also be a problem for shipping logistics in the wake of the ValuJet Flight 592 crash. Non-medical oxygen concentrators can be used as a feed gas to a medical oxygen system, like a hospital oxygen system, although FDA approval (or other region-specific regulatory, like CE) is required, additional filtration is generally required, and there may be other regulatory requirements as well.

See also


Wikimedia Foundation. 2010.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • Portable oxygen concentrator — A portable oxygen concentrator, also called a portable concentrator is a portable device used to provide oxygen therapy to a patient at substantially higher concentrations than the levels of ambient air. It is very similar to a home oxygen… …   Wikipedia

  • Oxygen therapy — Intervention ICD 9 CM 93.96 MeSH …   Wikipedia

  • Oxygen cocktail — The oxygen cocktail is a foamy substance containing a beverage drink (juice, milk, etc.) enriched in gaseous oxygen. The drink is used as part of oxygen therapy by a number of Russian medical institutions; their research suggest that the drink,… …   Wikipedia

  • Concentrator — In telecommunication, the term concentrator has the following meanings: In data transmission, a functional unit that permits a common path to handle more data sources than there are channels currently available within the path. A concentrator… …   Wikipedia

  • Oxygen — This article is about the chemical element and its most stable form, O2 or dioxygen. For other forms of this element, see Allotropes of oxygen. For other uses, see Oxygen (disambiguation). nitrogen ← oxygen → fluorine ↑ O ↓ …   Wikipedia

  • Oxygen mask — A plastic oxygen mask on an ER patient. An oxygen mask provides a method to transfer breathing oxygen gas from a storage tank to the lungs. Oxygen masks may cover the nose and mouth (oral nasal mask) or the entire face (full face mask). They may… …   Wikipedia

  • Oxygen bar — Interior of an oxygen bar An oxygen bar is an establishment, or part of one, that sells oxygen for recreational use. Individual flavored scents may be added to enhance the experience. The flavors in an oxygen bar come from bubbling oxygen through …   Wikipedia

  • Chemical oxygen generator — A chemical oxygen generator is a device releasing oxygen created by a chemical reaction. The oxygen source is usually an inorganic superoxide, chlorate, or perchlorate. A promising group of oxygen sources are ozonides. The generators are usually… …   Wikipedia

  • Emergency oxygen system — Aircraft emergency oxygen systems are emergency equipment fitted to commercial aircraft, intended for use when the cabin pressurisation system has failed and the level of oxygen in the cabin atmosphere drops below a safe level. It consists of a… …   Wikipedia

  • Chronic obstructive pulmonary disease — Classification and external resources Gross pathology of a lung showing centrilobular type emphysema characteristic of smoking. This close up of the fixed, cut lung surface shows multiple cavit …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”