What might happen if a diver exceeds the maximum operating depth for a given EANx mixture?

Exceeding the maximum operating depth for a specific EANx (Enriched Air Nitrox) mixture can lead to oxygen toxicity, which is a serious condition that may cause symptoms ranging from visual changes to convulsions. Each EANx blend has a predetermined maximum operating depth, determined by the partial pressure of oxygen at that depth. When a diver descends below this limit, the increased pressure causes the oxygen in the mixture to reach concentrations that can lead to toxic effects on the central nervous system.

Understanding this is crucial for ensuring diver safety. Oxygen toxicity can manifest in ways that may incapacitate a diver, making them unable to respond appropriately to their environment or emergency situations. This risk highlights the importance of adhering to depth limits for each specific gas mixture when planning dives.

In contrast, while options implying improved buoyancy control, enhanced visibility, or reduced dive times may have some association with diving, they do not address the significant risks related to exceeding maximum operating depths with specific gas mixes. Therefore, the right choice emphasizes the critical health implications of oxygen toxicity associated with diving beyond safe limits.