Which of the following is a requirement when planning Nitrox dives?

When planning Nitrox dives, careful calculations for oxygen exposure are essential because of the increased percentage of oxygen in Nitrox blends compared to regular air. Higher oxygen levels can lead to oxygen toxicity if divers exceed the maximum partial pressure of oxygen, typically set at 1.4 ATA for recreational diving, and 1.6 ATA in other limited circumstances. By carefully calculating the maximum operating depth for the specific Nitrox mix being used, divers can ensure they remain within safe limits while enjoying the benefits of reduced nitrogen absorption and extended no-decompression limits associated with Nitrox diving.

Moreover, knowing the limitations of oxygen exposure helps divers plan appropriately for their dive profile, manage their bottom times, and establish safe surface intervals to allow for proper gas off-gassing. This meticulous approach is cornerstone to safe diving practices when using Nitrox.

On the other hand, decremental depth approaches, standard air dive computations, and neglecting surface intervals do not align with the specific needs of Nitrox dive planning. While these concepts may apply to diving in general, they do not sufficiently address the unique considerations of breathing higher levels of oxygen, which is critical when using Nitrox.