What is the primary risk associated with Nitrox diving compared to regular air diving?

The primary risk associated with Nitrox diving compared to regular air diving is related to the specific composition of the gas being used, particularly the elevated levels of oxygen. Nitrox mixtures typically contain a higher concentration of oxygen than regular air, which consists of approximately 21% oxygen. While carbon monoxide poisoning can be a concern in various contexts, the primary risk in the context of Nitrox diving comes from exposure to high partial pressures of oxygen.

When diving with Nitrox, divers must be cautious of oxygen toxicity, which can occur at greater depths or when utilizing Nitrox blends with high oxygen content. This heightened exposure to oxygen can lead to symptoms ranging from visual disturbances to seizures, especially if a diver exceeds the maximum operating depth for a particular Nitrox blend.

The other options, while they might pose risks in diving, are not uniquely associated with Nitrox diving as compared to air diving. Equipment failure can happen regardless of the gas being used; increased nitrogen absorption is more relevant to diving at higher pressures and depths with air; and dehydration is a concern for all divers, not specific to the gas being breathed. Thus, the elevated risk of oxygen toxicity makes the primary risk associated with Nitrox diving distinct.