Which action is true regarding recovery after a hypoxia event once on the surface?

• A. The mouthpiece should be removed to allow the diver to breathe fresh air
• B. Continue breathing through the mouthpiece to acclimate
• C. Return to the water immediately for a controlled test dive
• D. Call fellow divers to assist while still submerged

Answer: (C)

Recovery after a hypoxia event on the surface centers on confirming full recovery and the system is functioning before resuming diving. A controlled re-entry into the water, done under supervision, provides a safe setting to verify that symptoms have resolved, the breathing loop is delivering gas correctly, and the diver can manage buoyancy and cognitive load again. This method helps ensure readiness and catches any residual issues in a monitored environment, reducing the risk of another hypoxic incident during actual diving.

Removing the mouthpiece to breathe ambient air would disrupt the breathing system and safety mechanism; simply continuing to breathe through the mouthpiece to acclimate doesn’t address whether the equipment and physiology are back to baseline; asking others to assist while still submerged isn’t a safe or practical option. Returning to the water for a controlled test dive is the safest way to revalidate both the diver and the equipment before returning to more demanding tasks.