Oxygen Safety
Oxygen, the most abundant of the elements, makes up approximately 50 percent of the earth’s crust. In its free state, oxygen forms approximately one-fifth of air by volume. Although classified as a non-flammable gas, oxygen supports combustion. As an active element, it combines directly or indirectly with all the elements except the rare gases. Oxygen is an invisible gas that is colorless, odorless, and tasteless. To ensure your safety, thoroughly read and familiarize yourself with the safety information on this page and, if necessary, the additional information linked from this page.
Oxygen Safety Precautions:
Always take proper precautions when using oxygen gas for any application. Oxygen gas is safe when used properly. Oxygen on its own does not burn. However, oxygen vigorously accelerates the combustion of flammable materials. Follow these safety precautions when using oxygen from any source: oxygen concentrator, oxygen tank, etc.
-Place “Oxygen in Use” signs in visible areas.
-Never place the oxygen source, O2 concentrator or tank near an open flame (e.g., matches, lit candles, a stove in use). Keep the oxygen source and all piping at least six feet away.
-Always turn your oxygen off when not in use. Close valves on tanks, turn OFF the O2 concentrator.
-Check the oxygen tubing for cracks and leaks.
-Never smoke when the oxygen source is in your residence. Do not allow anyone else to smoke. Always have a “No Smoking” sign posted in a visible spot.
-Do not use your oxygen in an area where combustible materials, such as oils, greases, aerosol sprays, lotions, or solvents, are present.
-Do not use petroleum-based products while oxygen is in use. Avoid the use of products that contain alcohol.
-Keep and maintain high-quality, functional fire extinguishers on hand.
Oxygen Concentrator Safety Tips:
An oxygen concentrator produces oxygen from ambient air by purging nitrogen from the air and capturing only the oxygen from that process. An oxygen concentrator can be turnkey and completely packaged, or larger oxygen concentrators may have a separate air compressor, oxygen concentrator, and oxygen storage tank. In all cases oxygen is supplied at much lower pressures than an oxygen tank and minimal oxygen is in storage on the system. Therefore, an oxygen concentrator is inherently safer than oxygen stored in tanks. However, there are still safety tips to be aware of and adhere to listed below:
- Shut off the oxygen concentrator and close oxygen valves when not in use.
- Inspect tubing and connections regularly to ensure leaks are not present.
Turnkey Oxygen Concentrators:
-Do not use extension cords with the oxygen concentrator. Plug the oxygen concentrator cord directly into a grounded electric outlet.
-Plug the oxygen concentrator into an outlet by itself. Do not plug any other appliances into the outlet.
-Do not place the oxygen concentrator against the wall or restrict airflow around the unit in any way.
Industrial Oxygen Concentrators:
-Place oxygen storage tank in a safe location away from flames or other combustion sources.
-Close oxygen valves on the oxygen storage tank when not in use.
-Inpsect tubing, valves, and regulators to ensure there are no leaks or potential leak points.
-Ensure exhaust (nitrogen purge) is vented to a safe location to prevent oxygen-deprived enviromnents.
Oxygen Tank safety tips:
Oxygen is pressurized at 2,000 – 2,200 PSI in an oxygen storage tank. Pure oxygen at high pressures can create combustion in the presence of oils and grease. Other materials may catch fire spontaneously with pure oxygen at high pressures. Certain safety precautions must be taken into account when using oxygen tanks as an oxygen source.
-Use only materials. (piping, valves, regulators, etc.) that are oxygen compatible.
-Within the oxygen plumbing system, use components that are “cleaned for oxygen service” This ensures all potentially flammable oils, greases or other combustible compounds are removed.
-Shut off all oxygen valves when the tank is not in use.
-If a protective cover is provided for the valve, ensure it is in place when the oxygen tank is transported, even a short distance.
-Use oxygen flow-meters and check oxygen flow when oxygen is in use to ensure the proper oxygen flow is used.
-Check the oxygen gauge and ensure sufficient oxygen pressure is present for operation at all times.
Liquid Oxygen tank Safety (LOX):
Liquid Oxygen (LOX) is the name used for oxygen stored in the liquid state. Liquid oxygen is stored at a high pressure to maintain the liquid state of oxygen.
-Venting – Liquid oxygen tanks are designed to be stored under stable pressures and are designed with built-in pressure relief valves. Due to this, the pressure relief valve may release oxygen gas during normal storage of the LOX tank.
-Temperature change – Liquid oxygen leaves the tank at extremely cold temperatures as it is converted from a liquid to a gas with a Dewar equipped on the tank. Due to the cold temperatures, the oxygen gas may freeze anything it comes in contact with. Skin cells will be destroyed instantly. Plastic materials may become brittle and break; therefore, ensure tubing used is capable of withstanding the temperature range they will be exposed to.
-Oxygen expansion – Liquid oxygen expands to gaseous oxygen at a ratio of 860:1. Therefore any leaks or accidental discharges of liquid oxygen into a room may create elevated oxygen levels in the room very quickly. Ensure the room is well ventilated and proper safety equipment is in place to prevent combustion.
Material Compatibility with Oxygen:
Ensure all piping and materials used to plumb oxygen gas are compatible with oxygen.
When using oxygen tanks, ensure all components used are “cleaned for oxygen service.” All oils, greases, and other potentially organic materials are removed from the system to prevent spontaneous combustion. Equipment designed and cleaned for oxygen service will be constructed from materials and components that have been tested and proven compatible and safe for oxygen use.
-O-rings and gaskets – avoid natural rubber, Buna-N and other organic-based rubber materials. Use EPDM, Viton, Teflon, Silicone and other synthetic elastomers.
-Metal components – avoid iron materials. Use quality copper, brass, aluminum, or stainless steel materials.
-Oxygen Hoses – ensure the hose material used is compatible with oxygen. Teflon and Silicone are good choices.
-Lubricants – most all lubricants should be avoided. If a lubricant is required, ensure it is manufactured specifically for use with oxygen.
Safety Publications
Additional information can be found in the following articles:
-Occupational Safety and Health Administration (OSHA) Bulk Oxygen Systems
-Compressed Gas Association (CGA) Oxygen and Oil Don't Mix Poster
-Canadian Centre for Occupational Health and Safety (CCOHS) Cryogenic Liquids - Hazards
-National Aeronautics and Space Administration (NASA) Safety Standards for Oxygen and Oxygen Systems
Oxygen Suppliers Safety Resources:
-Praxair/Linde Safety Data Sheet (SDS)
"Installation of Bulk Oxygen Systems at Consumer Sites;"
NFPA No. 50; National Fire Protection Association; 1 Batterymarch Park; P. O. Box 9101; Quincy, Massachusetts 02269-9101 USA.
"Oxygen;"
Pamphlet G-4; Compressed Gas Association; 1725 Jefferson Davis Highway; Arlington, Virginia 22202-4102 USA.
"Cleaning Equipment For Oxygen Service,"
Pamphlet G-4.1; Compressed Gas Association; 1725 Jefferson Davis Highway; Arlington, Virginia 22202-4102 USA.
Video:
The International Ozone Association (IOA) put together the video below with great information on the safe use of oxygen and ozone.