What is the effect of higher oxygen concentrations in diving?

Higher oxygen concentrations in diving have a direct effect on oxygen absorption by the body. As the percentage of oxygen in the breathing gas increases, the partial pressure of oxygen also rises, which leads to greater amounts of oxygen being absorbed into the bloodstream. This is particularly important for divers using Enriched Air Nitrox, as it allows for more efficient utilization of oxygen during dives, which can improve overall efficiency and potentially extend bottom times at certain depths.

While the other choices can be associated with diving in various contexts, they do not align as closely with the specific implications of increased oxygen concentrations. Enhanced buoyancy, for instance, is primarily influenced by the type of gas mixture and diver equipment rather than oxygen levels alone. Nitrogen narcosis is more associated with nitrogen levels rather than the oxygen concentration, and while some studies suggest that higher oxygen levels might impact night vision, this is not a primary effect noted in the context of diving operations. Thus, the increased oxygen absorption is the most significant and relevant effect of higher oxygen concentrations in this scenario.