Method of and apparatus for bouyancy compensation for divers

An improved buoyancy compensation device having a lesser change in buoyancy with depth than conventional buoyancy compensation devices which use ambient pressure bladders is disclosed. The improved device comprises one or more elastic members that, throughout the working range of diving pressures and volumes, is always elastic and, when pressurized, maintains an internal air pressure that is always greater than the ambient pressure at any dive depth. The invention also relates to a method of providing a buoyancy compensation device with an elastic member having a lift versus depth characteristic that approaches the lift versus depth characteristic of a constant or fixed volume buoyancy compensation device.