The Buoyancy Control Pyramid

The illustration below shows the “buoyancy control pyramid.”

  • Buoyancy Control Pyramid

    At its peak is breath control — a diver’s ability to make minute buoyancy adjustments by inhaling and exhaling more or less deeply.
  • The next level in the pyramid is BC adjustment — the ability to compensate for exposure suit compression and expansion by adding to or removing air from the BC.
  • The foundation of the pyramid is proper weighting — using only that weight which is necessary and no more.

Of these three elements, none is more important than proper weighting.

If you are not properly weighted, you are not controlling buoyancy; you are just spinning your wheels.

Overweighted divers pose a risk to the environment and to themselves. They need to make BC adjustments more frequently, as they must compensate not only for suit compression, but also for the compression of the additional air that must be in their BCs to offset the unnecessary weight. This leads to increased drag, inefficient body position and poor gas consumption. Overweighted divers are also more likely to be the victims of diving accidents than divers who are properly weighted.

Every time you dive, your goal should be to use the least weight possible. The best way to check this is at the end of the dive, during your safety stop, with 500-1,000 psi in your tank. If properly weighted, you’ll be able to hover at safety-stop depth with no air in your BC.

You can’t build a lasting structure without a solid foundation. When it comes to buoyancy control, that foundation is proper weighting.