What condition is primarily prevented by using Nitrox?

Using Nitrox primarily helps to prevent nitrogen narcosis because it reduces the proportion of nitrogen in the breathing gas mix. Nitrogen narcosis, often referred to as "rapture of the deep," is a condition that occurs when divers breathe high levels of nitrogen at depth. As the partial pressure of nitrogen increases, it can lead to impairment of cognitive function and motor skills, similar to intoxication. By using a Nitrox blend, which has a higher concentration of oxygen and a lower concentration of nitrogen compared to air, divers can minimize the effects of nitrogen narcosis during deeper dives.

While decompression sickness and diving fatigue are also concerns for divers, Nitrox specifically addresses the risks associated with nitrogen absorption and narcosis. Decompression sickness primarily results from changes in pressure during ascent and nitrogen coming out of solution in the body, while diving fatigue can be affected by various factors, including physical exertion and hydration, rather than the gas mix itself. Barotrauma, which involves injuries caused by pressure changes affecting air-filled spaces in the body, is not specifically addressed by the use of Nitrox either. Thus, the primary benefit of Nitrox in terms of preventing narcosis is clear.