Differences Between Nitrox & Oxygen Regulators

A nitrox scuba regulator and an oxygen scuba regulator are actually the same thing, though nitrox regulators and air regulators are not. Nitrox refers to a special mix of air that scuba divers can use with a higher-than-normal concentration of oxygen; the name "oxygen regulator" refers to the same high concentration of oxygen. Scuba diving with an air tank concentration below 40 percent oxygen is considered regular air. Regulators for nitrox diving and air diving differ in many ways, including the materials and chemicals used to make each.

  1. Materials

    • The main difference between nitrox and air regulators is the materials each are made out of. Nitrox regulators cannot be made of aluminum or titanium, since both metals can react in the presence of higher oxygen concentrations. Air regulators are rated to 40 percent oxygen concentrations in the United States, whereas any concentration greater requires a nitrox regulator.

    Dangers

    • Nitrox regulators require more care than air regulators in order for them to function safely. For nitrox diving, only oxygen-compatible O-rings and lubricants can be used to avoid producing potentially harmful gases. If a nitrox regulator has not been properly cared for or oxygen-cleaned, trace deposits inside the regulator can also react violently with the concentrated oxygen.

    Oxygen Compatible

    • When using a nitrox mix, divers must ensure that all components of the regulator are nitrox-ready. This means that not only should the second stage be made of materials compatible with nitrox, but the hoses must be as well. Do not use hoses or other parts from an air regulator with a nitrox-compatible second stage, as the hoses and lubricants will be compromised. Even the swivel pin at the joint between the contents gauge and the regulator hose must be oxygen-compatible to safely dive with a nitrox mix.

    Oxygen Clean

    • When diving using regular air, the only care requirement is to keep the regulator clean and free of salt and sediments. When using a nitrox mix to dive, however, all components of the nitrox regulator must also be oxygen-clean. Oxygen-clean means the regulator has been treated to remove any sediments or trace elements that could react with the purer oxygen; many nitrox-compatible regulators come oxygen-clean. In order to safely dive with a nitrox mix, your regulator must be both oxygen-compatible and oxygen-clean.