What is the RNT Exception Rule primarily concerned with?

The RNT Exception Rule, or the Residual Nitrogen Time Exception Rule, primarily focuses on decompression times. This rule is particularly relevant in mixed gas diving and allows divers to account for residual nitrogen from previous dives when planning their next dive. Essentially, it provides guidelines on how to adjust decompression schedules to mitigate the risks associated with nitrogen buildup in the body.

Understanding decompression times is crucial for divers, as improper management of these times can lead to decompression sickness, commonly known as "the bends." The RNT Exception Rule aids divers in calculating their ascent and safety stops correctly to reduce the likelihood of bubbles forming in the bloodstream due to excessive nitrogen buildup, ensuring safer diving practices.