The breathing system has 5 components:

1. Compressor

Raises the pressure of the gas from the return umbilical to pump it through the other components

2. Reprocessing unit

Removes CO 2, water, other impurities and excess gas. Adds oxygen and diluent gasses as required from storage cylinders

3. Umbilical

Supplies gas and communications to the diver and returns expired gas to the surface

4. Backpack

Contains constrained double counterlung and back-up rebreather

5. Mouthpiece

Connects backpack to diver

There are various options for each component providing a range of combinations to suit various types of dive and dive platforms. Key factors are:

• 6. Depth of dive; 60m, 150m, 500m
• 7. ‘Bounce’, ‘Wet Bell’ or ‘Saturation diving’
• 8. Size of dive area
• 9. Need for communications
• 10. Size of Dive Platform
• 11. Availability of power
• 12. Portable or permanent installation
• 13. Number of divers on each system