Which method helps divers maintain neutral buoyancy?

Maintaining neutral buoyancy is essential for divers to move through the water efficiently and safely, minimizing the energy expended and enhancing the overall diving experience. Adjusting air in the buoyancy control device (BCD) according to depth is crucial because buoyancy in water varies with pressure: as a diver descends, the increased pressure compresses the air in the BCD. To counteract this and maintain neutral buoyancy, divers need to add air to their BCD as they go deeper.

This practice allows for proper buoyancy control, ensuring the diver neither sinks nor floats uncontrollably, leading to a stable and composed underwater presence. Additionally, as a diver ascends, the pressure decreases, and air expands in the BCD, so it is equally important to release some air to prevent rapid ascents or unwanted buoyancy changes.

In contrast, adjusting weights only at the surface is not effective because it does not account for changes in buoyancy due to depth. Constantly expelling air from the BCD can lead to being negatively buoyant, making it difficult to ascend or maintain stability in the water. Increasing intake of air in the lungs can temporarily affect buoyancy but is not a reliable method for achieving neutral buoyancy, as it can