What Does Nitrox-Ready Mean?

When the SCUBA diving community prepares an item for use with breathing gases containing high oxygen percentages or pure oxygen, they generally think in terms of washing it with detergents, replacing rubber parts such as O-rings and seals with oxygen-compatible equivalents and reassembling with oxygen-compatible lubricants. However, most other industries working with very high pressure oxygen (over 20,000 psi service pressures!) have a very different standard known as oxygen service.

Oxygen service means the materials are both:

• Oxygen Compatible -- compatible with high concentrations of oxygen.
• Oxygen Clean -- free of hydrocarbon contamination and particulate matter.

True oxygen cleaning of an oxygen compatible component (often made from special metal alloys such as monel) takes place in a special clean room, whose atmosphere is free of dust and contaminants. Once the component is free of hydrocarbons and other combustible elements, it is sealed within a sterile environment and never again exposed to normal atmospheric dust, moisture, and contaminants. Only then is the item said to be suitable for oxygen service.

Dive Gear Express offers diving products labeled Nitrox Ready, whose oxygen-compatible components are free of hydrocarbons and other flammable contaminants. The metal components are usually steel, aluminum or brass; which are suitable for use with oxygen at the pressures encountered in diving actvities. The lubricant used in assembly is oxygen-compatible. The O-rings are made from oxygen-compatible materials. These components are not, however, assembled in a clean room or sealed in a sterile environment. As a result, we do not label the products as suitable for oxygen service, although they are generally considered to meet oxygen service criteria at pressures encountered in the diving community.

In our opinion, we believe the equipment we sell is suitable for use with pure oxygen at gas pressures up to 3000 psi only if precautions are taken: use oxygen compatible materials, make sure it's kept very clean during assembly and use, open valves very slowly. However, we are not experts on this issue and many experts would disagree based on aerospace industry standards. There is a DOT standard for oxygen cleanliness in cylinders, and our cylinders meet the DOT standard as shipped with original factory seals intact. The DOT maximum fill pressure in cylinders in U.S. is 3000 psi, although in other parts of the world we have seen pressures as high as 450 Bar. We have some seen some aerospace oxygen systems that operated as high as 20,000 psi.

Our gas boosters, and some scuba regulators, also meet aerospace standards for oxygen cleanliness when they are sealed in the manufacturer original packaging. In addition to those items, Dive Gear Express offers diving products labeled Nitrox Ready, whose oxygen-compatible components are free of hydrocarbons and other flammable contaminants. These components are very clean, but have not had a cleanliness test and are not assembled in a clean room or sealed in a sterile environment as required by aerospace standards.

Studies have demonstrated when any dive equipment is used in the environment typical of diving activities, it will immediately become so contaminated that it no longer meets any formal standard for oxygen service. Oxygen-related fires and explosions occur very infrequently, but are usually catastrophic when they happen. Because we have no way to control how our products are used and maintained, you must make the final decision to assume the risks associated with using our equipment with pure oxygen or oxygen enriched mixtures.