TDI Air Diluent CCR Diver
Enter the world of rebreather diving, control your breathing gas in real time, and operate a closed circuit system with precision
Duration
5 days, 6 dives
Max Depth
40m / 130ft
Level
Technical (CCR Entry – Air Diluent)
Next Step
CCR Decompression Procedures
Overview
The TDI Air Diluent CCR Diver course is the entry-level certification for closed circuit rebreather diving, introducing divers to fully closed-loop systems using air as a diluent.
Unlike open circuit or semi-closed systems, CCRs allow divers to control partial pressure of oxygen (PO₂) in real time, optimising gas efficiency, reducing decompression stress, and extending bottom time.
Training focuses on unit-specific operation, life-support management, and failure response, where precision, discipline, and continuous monitoring are critical.
Divers learn to manage oxygen addition, loop volume, electronics, and bailout procedures, while maintaining control under increasing task loading.
At N9BO℠, this course is delivered as high-discipline systems training, building operational awareness, redundancy thinking, and precise execution.
Course Facts
- Course name: TDI Air Diluent Closed Circuit Rebreather Diver (Unit Specific)
- Level: Technical rebreather (entry-level CCR)
- Minimum prerequisites: Minimum age 18, Minimum 60 logged dives, TDI Advanced Nitrox Diver (or equivalent)
- Ratio: Maximum of 4 students per instructor (small groups recommended for quality training)
- Configuration: Unit-specific CCR with onboard oxygen, air diluent, and bailout system
- Depth / environment: Maximum depth 40 metres / 130 feet, Minimal decompression only (≤ 5 minutes at 6m / 20ft), and limited by a maximum PO₂ of 1.6 ATA and gas selection
- Format: Academic development + unit workshop + confined water + open water dives
- Duration: Typically completed in 5 days (Minimum 6 open water dives with at least 360 minutes accumulated bottom time)
What You’ll Learn
- Assemble and configure a unit-specific CCR system.
- Calibrate and monitor oxygen sensors and electronics.
- Control PO₂ setpoints and gas addition.
- Execute bailout procedures to open circuit.
- Respond to failures including flooding, gas issues, and system faults.
Prerequisites
- Be at least 18 years old.
- Have a minimum of 60 logged dives.
- Hold TDI Advanced Nitrox Diver certification (or equivalent).
- Be medically fit for diving.
FAQ
A CCR is a fully closed-loop system that recycles breathing gas and maintains a controlled oxygen partial pressure, allowing optimal gas efficiency and extended dive time.
You are certified to a maximum of 40 metres / 130 feet, using air as a diluent with minimal decompression limits.
Key risks include:
- Hypoxia / hyperoxia
- CO₂ breakthrough (scrubber failure)
- Loop flooding
- Electronics or sensor failure
This course trains you to detect and respond immediately to system failures.
No, but CCR diving requires:
- Higher discipline
- Continuous monitoring
- Strong procedural awareness
You are qualified to conduct dives using a specific CCR unit with air diluent, managing PO₂, gas supply, and life-support systems within the limits of your training, including minimal decompression exposures.
Ready to Enter CCR Diving?
Send us your certifications and experience. We’ll guide you into CCR diving with precision, discipline, and full system control.
Go Pro with TDI Air Diluent CCR Instructor
Advance into rebreather instruction and train divers to operate closed circuit life-support systems safely and effectively on specific CCR platforms.
