When would a diver need to switch to air instead of Nitrox?

The need for a diver to switch from Nitrox to air arises when the planned dive exceeds the maximum operational depth recommended for the specific Nitrox blend being used. Each Nitrox mix has a maximum operating depth based on its oxygen content, which is crucial for avoiding oxygen toxicity. If a diver intends to go deeper than this limit, using air, which has a lower oxygen content and thus a higher maximum operational depth, is the safer choice.

Utilizing a Nitrox mix beyond its maximum operational depth increases the risk of oxygen toxicity, which can lead to serious health issues such as seizures. Therefore, understanding the limitations of the gas mixture is essential for maintaining safety during dives, and switching to air when necessary is a critical safety measure.

The other considerations, such as water temperature, dive time (including night dives), or the use of traditional tanks, do not directly impact the decision to switch gas mixtures based on depth-related safety concerns.