Oxygen prescribed by a doctor is almost 100 percent pure, as opposed to the air we normally breathe which is approximately 21 percent oxygen and 79 percent other gases. A physician prescribes home oxygen use stating the amount, such as 2 liters per minute, and also the frequency, such as at night, continuous or on an as-needed basis. Low-flow home oxygen is inhaled through a plastic device called a nasal cannula. Higher flow rates will require an oxygen mask. How much oxygen used on a daily basis and a person's activity level will determine the type of home oxygen system needed.
Liquid Oxygen
In a liquid oxygen system, a large reservoir and a small portable carrier are available, allowing a person to use the smaller unit when away from home. The carrier has a shoulder strap and contains from two to eight hours of oxygen, depending on the prescribed liter flow. The reservoir has adapters to refill the portable unit. The larger system can be equipped with a humidifier, flow meter and tubing to deliver oxygen at home when the portable unit is unnecessary, such as during sleep or when completing daily chores around the house.
Compressed Oxygen
Compressed oxygen cylinders or tanks come in different sizes for different needs. Large cylinders are for stationary use while sleeping or in the home. Small cylinders are available for taking outside the home when walking or traveling in the car. A humidifier can be attached to the larger cylinders if needed. According to the Cleveland Clinic, the large "H" or "J" cylinders will last two to three days at 2 liters per minute, while the smaller "D" or "E" cylinders will last from one to three hours at the same liter flow.
Oxygen Concentrator
Because air is 21 percent oxygen and 79 percent other gases, including nitrogen, an electrically powered concentrator can absorb the nitrogen in the air, thereby increasing the percentage of oxygen. According to the National Lung Health Education Program, these systems are not portable and do not work well for high oxygen flow rates greater than 4 liters per minute. However, as a stationary home oxygen system, an oxygen concentrator can be less expensive than liquid or compressed oxygen systems. Small compressed oxygen cylinders are provided for portability, while the larger cylinders can be used as backup in the event of a power failure.
Safety When Using Home Oxygen Systems
Oxygen is a relatively safe gas; however, while it does not burn or explode on its own, it does support combustion. According to the Cleveland Clinic, because oxygen cylinders are compressed at a high pressure, they should be handled with the utmost care. Oxygen equipment suppliers are responsible for showing the user proper handling and storage procedures for all home oxygen systems.
