Mixed Gas CCR Diver

Skills

• Assemble the unit according to the manufacturer’s specifications using the manufacturer’s manual/checklist.
• Demonstrate familiarity with basic and intermediate hand signals.
• Select and prepare the appropriate equipment for a mild environment with long decompression stops.
• Conduct team drills for the deployment of lift bags and rescue procedures.
• Conduct buddy rescue drills.
• Properly analyze all gas mixtures to be used.
• Demonstrate adequate pre-dive planning.
• Perform pre-dive checks using the TDI pre-dive checklist.
• Use START* before each dive.
• Stress analysis and mitigation.
• Demonstrate a good understanding of team members through communication, proximity, and team-oriented diving practices.

• Demonstrate buoyancy control; the ability to float in a fixed position in the water column without moving the hands or feet.
• Removal and replacement of the mask; deployment of the backup mask.
• Correctly execute a recovery following a system failure and complete the dive and decompression using open-circuit gases transported from a depth greater than 30 meters/100 feet.
• Demonstrate the ability to connect to and share outboard gas, including the exchange of outboard rescue cylinders.
• Correctly execute a recovery following a system failure and complete the dive and decompression with the unit in manual mode.
• Blackouts and gas loss, correct selection and switch to outboard gases.
• Broken hoses, catastrophic failure scenarios.
• Flooded absorbent container.
• Cell malfunctions.
• SCR drill (minimum 10 minutes).
• Oxygen rebreather mode at depths less than 6 meters / 20 feet
• Stop at 3 to 6 meters / 10 to 20 feet during descent to check for a leak bubble.
• Demonstrate proficiency in handling 2 rescue cylinders, including dropping and retrieving them while maintaining position in the water column.
• Deployment of a lift bag / delayed surface marker buoy (DSMB) at depth and mid-water
• Simulation of lift bag / DSMB deployment failure.
• On 2 of the dives, demonstrate an ascent using an ascent reel and lift bag and perform a staged decompression.
• Monitoring of electronic systems for PPO₂ levels.

• Validation checks of the tanks to ensure proper use of diluent and oxygen.
• Correct execution of the dive within all predetermined dive limits.
• Demonstration of decompression stops at predetermined depths.
• Demonstrate a controlled ascent with a simulated toxic diver, including a tow to the surface of at least 50 meters / 165 feet with removal of equipment at the surface, in water too deep to stand.