Which gas is primarily associated with the risks of oxygen toxicity while using Nitrox?

The principal gas associated with the risks of oxygen toxicity when using Nitrox is oxygen. In diving with Nitrox, which is a mixture of nitrogen and oxygen with a higher concentration of oxygen than regular air, divers must be aware of the potential for oxygen toxicity. This condition can occur when the partial pressure of oxygen in the breathing gas exceeds safe limits, often measured in atmospheres absolute (ATA).

As divers go deeper, the pressure increases, and so does the partial pressure of oxygen in the breathing mix. If the partial pressure of oxygen becomes too high—typically above 1.4 ATA—divers may start to experience symptoms of oxygen toxicity, which can range from visual disturbances to convulsions. Therefore, understanding the proportion of oxygen in the Nitrox mix and monitoring depth is crucial for preventing toxicity during a dive.

Other gases such as nitrogen, carbon dioxide, and helium do not pose the same direct risk of oxygen toxicity as oxygen does, even though they may have their own risks associated with diving. The focus on oxygen and its potential dangers is essential for safe diving practices when using Nitrox.