What factor is crucial in determining the depth and duration of a Nitrox dive?

The specific Nitrox mixture used is crucial in determining the depth and duration of a Nitrox dive primarily due to its effect on the partial pressures of oxygen and nitrogen in the gas mixture. Nitrox is typically a blend of nitrogen and oxygen, with a higher proportion of oxygen compared to air, which can reduce the amount of nitrogen a diver absorbs during the dive. This shift allows divers to extend their bottom time at certain depths compared to diving with air, but it also requires careful consideration of the maximum operating depth associated with the oxygen content in the mixture to avoid oxygen toxicity.

Each specific Nitrox mixture has its own limits regarding the maximum depth a diver can safely reach based on the percentage of oxygen it contains. Higher percentages of oxygen are suitable for shallower dives but become hazardous at greater depths due to the increased partial pressure of oxygen, which can lead to toxic effects. Thus, when determining dive plans, divers must reference the specific mixture they intend to use and calculate depth and bottom time accordingly to ensure a safe and enjoyable dive experience.