What is the major benefit of diving with nitrox?

Diving with nitrox, which is a mixture of oxygen and nitrogen with an enriched oxygen content compared to regular air, primarily offers the benefit of a lower concentration of nitrogen relative to air. When divers use nitrox, the reduced nitrogen levels directly correspond to the gas that primarily limits bottom time when diving at depths. This means that divers can stay at depth longer without exceeding their no-decompression limits, which is particularly advantageous in recreational diving scenarios.

This benefit is crucial as it allows divers to minimize their risk of nitrogen narcosis and decompression sickness, which are associated with higher nitrogen levels in the body. By having a higher percentage of oxygen and a lower percentage of nitrogen, divers on nitrox can enjoy longer dives or shallower safety stops, enhancing the overall diving experience.

The other options do not provide the same advantages; for instance, a higher concentration of nitrogen would actually have the opposite effect by limiting time at depth. Increasing carbon dioxide levels is undesirable and would create respiratory issues, while buoyancy control can be improved through other means independent of the breathing gas used.