 Wet bells are used for air and mixed gas, and divers can decompress using oxygen from a mask at 12 m.

The launch and recovery system (LARS) is the equipment used to deploy and recover a stage or diving bell.Reducing the partial pressure of the inert gas component of the breathing mixture will accelerate decompression as the concentration gradient will be greater for a given depth.This is achieved by increasing the fraction of oxygen in the breathing gas used, whereas substitution of a different inert gas will not produce the desired effect.