It is critically important that the fully inflated buoyancy compensator can support the diver with the maximum equipment load on the surface at the start of a dive, and with maximum suit compression at the maximum depth before much gas is used up. There have been fatalities due to overloading the BCD. On the other hand, buoyancy control is easiest with the lowest practicable volume of gas in the BCD and dry suit, as these volumes change with depth changes, and must be adjusted to remain neutral.