SDI Open Water Scuba Diver Practice Exam 2026 – Complete Test Prep

To achieve neutral buoyancy while diving, adjusting your buoyancy control device (BCD) is essential. Neutral buoyancy occurs when your body is neither sinking nor floating, allowing you to hover effortlessly in the water column. A BCD is designed specifically for this purpose; it allows divers to add or release air, thereby changing their overall buoyancy.

When air is added to your BCD, it increases your buoyancy and can help you float. Conversely, releasing air reduces buoyancy, allowing you to sink. By making precise adjustments to the air in your BCD, you can find the right balance that achieves neutral buoyancy, making it easier to conserve energy and enjoy the underwater environment.

In contrast, simply adding more weight or removing all weight can lead to problems. Adding weight can make you sink more quickly, while removing all weight can cause you to float uncontrollably. Breathing only shallow breaths may impact your buoyancy slightly, but it is not the most effective or reliable method for achieving neutral buoyancy. This is why adjusting your BCD is the optimal approach for maintaining that desired balance in the water.