Take your first step into the world of closed circuit rebreather diving with the TDI MOD1 Air Diluent Diver course
TDI Air Diluent Diver Course (MOD1 CCR)
The TDI MOD1 Rebreather Course, officially known as the TDI CCR Air Diluent Diver course, is the first level of training for divers entering the world of closed circuit rebreathers.
Take your first step into the world of closed circuit rebreather diving with the TDI MOD1 Course in Phuket, Thailand with experienced instructors who dive CCR as their primary equipment. Experience longer dive times, reduced gas consumption, and the unique advantage of silent underwater exploration while using the latest CCR technology.
Unlike traditional open circuit scuba equipment, a closed circuit rebreather (CCR) continuously monitors and maintains a constant partial pressure of oxygen, delivering an optimal breathing mix throughout your dive. The result is increased efficiency, quieter dives, and closer encounters with marine life.
What is the TDI MOD1 Rebreather Course?
The TDI MOD1 Rebreather Course is the entry-level certification for closed circuit rebreather diving. It qualifies divers to conduct no-decompression dives to a maximum depth of 30 metres using air diluent, while learning essential CCR skills including gas management, buoyancy control and emergency procedures.
This comprehensive TDI CCR Air Diluent course in Phuket provides a strong foundation in rebreather diving, equipment handling, and CCR maintenance. You will learn how to safely operate, maintain, customise, and troubleshoot your rebreather system while building confidence in real diving conditions down to a maximum depth of 30m.
During this course, your certified TDI Instructor will teach you the essential knowledge and practical skills needed to safely conduct no-decompression CCR dives to a maximum depth of 30 metres (100 feet) using air diluent.
Training includes:
- CCR setup and configuration
- Safe bailout procedures
- Advanced buoyancy control techniques
- In-water problem solving
- Rebreather servicing and maintenance workshops
- Dive planning and emergency management
By the end of the course, you will have the skills and knowledge required to dive your unit safely and confidently.
What is the difference between Open Circuit diving and Rebreather diving?
Open circuit scuba diving is the most common form of diving, where each breath is taken from a tank and exhaled as bubbles, limiting dive time and creating noise underwater. In contrast, closed circuit rebreather (CCR) diving recycles your breathing gas, removes carbon dioxide, and maintains optimal oxygen levels, allowing for significantly longer, quieter, and more efficient dives. This results in extended bottom times, improved buoyancy control, and closer interactions with marine life, making rebreathers a popular choice for divers looking to progress beyond recreational limits into a more immersive and advanced diving experience.
As Rebreather Instructor Trainer Kevin Black often says “It is like a nitrox blender on your back giving you the best mix of gas for the depth you are diving.
CCR diving is especially popular with:
- Underwater photographers and videographers
- Divers wanting longer bottom times
- Marine life enthusiasts seeking quieter interactions underwater
- Technical divers progressing into advanced equipment configurations
Who Is This Rebreather Course For?
This course is ideal for certified divers who want to advance their diving skills and explore the benefits of closed circuit rebreather technology.
What You Will Learn
The TDI CCR Air Diluent Diver Course covers both theory and practical training, including:
- History and evolution of rebreathers
- Differences between Open Circuit (OC), Closed Circuit (CCR), and Semi-Closed Circuit Rebreathers (SCR)
- CCR mechanics and system design
- Gas physiology and oxygen management
- Proper scrubber packing procedures
- Electronic and manual system maintenance
- Dive planning and dive table usage
- Dive computer operation
- Emergency procedures and bailout protocols
- Pre-dive safety checks and checklists
- Buoyancy control using loop volume management
- Monitoring oxygen partial pressure levels
- Surface marker buoy (SMB) and reel deployment
- Safe dive execution within planned limits
- Post-dive cleaning and equipment care
- Ongoing diver maintenance of the unit
Students must also successfully complete the TDI CCR Air Diluent examination with a minimum passing score of 80%.
Course Prerequisites
To enrol in the TDI CCR Air Diluent Diver Course, you must:
- Be at least 18 years old
- Have a minimum of 100 logged open water dives
- Hold a TDI Nitrox Diver certification or equivalent from a recognised training agency
Course Schedule
(Minimum 5 Days)
- Day 1 Classroom sessions and workshop training
- Day 2 Workshop sessions and confined water/pool training
- Day 3 – 5 Three open water boat dives
Additional Training Recommendations
As with all technical diving courses, we strongly recommend allowing an extra day in your schedule. Additional time may be needed due to weather conditions, logistics, or to ensure all performance requirements are comfortably achieved. Training dives are conducted in the warm waters of Phuket, with access to local dive sites ideal for developing CCR skills in real conditions.
Many students also choose to add extra training dives with their instructor to further develop confidence and refine CCR skills.
Benefits of Completing This Course
After successful certification, divers may independently conduct dives using the CCR unit they were trained on, without direct instructor supervision, within the limits of their certification level.
CCR diving offers several advantages, including:
- Extended dive times
- Reduced gas consumption
- Optimised breathing gas throughout the dive
- Quiet underwater experience
- Improved marine life interactions
- Reduced bubble noise and disturbance
Rebreather Rental and Purchase Options
If you are considering purchasing a new or second-hand CCR unit, our team can help arrange delivery to Thailand before your course begins. Your instructor can also advise you on equipment options, pricing, and potential tax advantages.
For divers who prefer not to purchase immediately, we also offer “try before you buy” CCR rental options on selected units.
Why Train With Us for Your MOD1 Course?
- number of CCR dives taught
- instructor experience
- real diving environment
- small group sizes
- equipment quality
The team at Tech Dive Asia have introduced hundreds of divers to their first breath underwater without bubbles on many different rebreather platforms.
Contact Us
Have questions or need help? Use the form to reach out and we will be in touch with you as quickly as possible.