Why is continuous monitoring of oxygen levels critical when using Nitrox?

Continuous monitoring of oxygen levels is critical when using Nitrox because it helps prevent excessive exposure to oxygen pressure. Nitrox is a blend of nitrogen and oxygen, with higher percentages of oxygen compared to standard air. While this mixture can reduce nitrogen absorption and extend bottom time, it also increases the risk of oxygen toxicity if the partial pressure of oxygen exceeds safe limits during a dive. Monitoring ensures that divers stay within safe exposure levels, safeguarding them from potentially serious health risks associated with oxygen toxicity, such as seizures and other neurological effects.

The other options relate to aspects of diving but do not directly pertain to the critical reason for monitoring oxygen levels. Proper buoyancy control, for example, is influenced by factors such as equipment, diver experience, and environmental conditions rather than the oxygen content within the breathing mix. Enhancing underwater visibility and minimizing tank weight are not directly related to the management of oxygen levels and do not address the specific safety concerns of using enriched air.