TDI Technical Diving
TDI Extended Range Diver Course
Develop the planning, equipment and team skills required for extended-range diving using air as the bottom gas and nitrox or oxygen for decompression. The course treats deep-air exposure conservatively and places disciplined decision-making ahead of depth.
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Who This Course Is For
- Advanced Nitrox and Decompression Procedures divers progressing to extended range.
- Experienced technical divers operating where helium access is limited.
- Divers preparing for Trimix or Advanced Trimix training.
Prerequisites and Readiness
- Minimum age 18.
- TDI Advanced Nitrox Diver and TDI Decompression Procedures Diver, or equivalent.
- Proof of at least 100 logged dives, including 25 deeper than 30 metres.
- Recent experience with the selected technical configuration and staged decompression.
How Training Works
The course includes four open-water dives. All four are deeper than 33 metres and at least two are deeper than 40 metres, with progression to a maximum of 55 metres. Depth progression remains subject to conditions, student performance and instructor judgement.
Course duration is performance-based. Meeting minimum attendance or dive numbers does not guarantee certification; all required knowledge and skills must be demonstrated consistently.
Skills and Knowledge
Continue Your Development
Technical capability is developed through deliberate practice and experience between formal courses. Your next step should reflect your recent diving, equipment configuration and objectives.
The Blue Water Ascent approach
Competence Before Certification
We coach understanding, judgement and repeatable performance—not minimum-standard completion. Training is adapted to the diver while every certification requirement and course limit is preserved.
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