Which gases are primarily monitored when diving with Nitrox?

When diving with Nitrox, the primary concern is the monitoring of oxygen and nitrogen, as these are the main components of the breathing gas mixture. Nitrox, which is a blend of oxygen and nitrogen, is used to enhance safety and extend bottom times while minimizing the risks associated with nitrogen narcosis and decompression sickness.

Oxygen is crucial to monitor because, unlike air, which contains approximately 21% oxygen, many Nitrox blends have a higher percentage of oxygen. This increased oxygen level can lead to oxygen toxicity if the partial pressure of oxygen exceeds safe limits during a dive, especially at deeper depths. Thus, understanding and calculating the percentage of oxygen in your Nitrox mix is vital to ensure safe diving practices.

Nitrogen is also monitored because it is the inert gas that can accumulate in the body during the dive. While Nitrox has less nitrogen compared to air, it still plays a key role in determining no-decompression limits and dive profile planning.

Other gases listed, such as helium, argon, and hydrogen, are either not part of typical Nitrox diving mixes or are not primarily of concern when assessing the risks associated with Nitrox diving itself. The emphasis on oxygen and nitrogen specifically aligns with the guidelines for safe Nitrox use,