Why is monitoring oxygen partial pressure important in nitrox diving?

Monitoring oxygen partial pressure is essential in nitrox diving primarily because it ensures compliance with dive table limits. When using enriched air nitrox, divers are exposed to higher oxygen concentrations than they would be with air, and therefore, it is necessary to keep track of the partial pressure of oxygen (PPO2) to avoid encountering toxicity, which can lead to serious health risks, including seizures.

The limits set in dive tables or computers help divers determine safe depths and times for diving with nitrox to manage the increase in oxygen exposure effectively. By monitoring PPO2, divers can ensure that they remain within these safe operational limits throughout their dive, allowing them to dive safely while utilizing the benefits of nitrox.

Other options may have some relevance in diving practices, but they do not directly address the critical concern of managing oxygen exposure, which is paramount in preventing oxygen toxicity and ensuring a safe diving experience.