Independent course guide · References checked 30 September 2026. Confirm current standards and your eligibility with an authorised instructor.
Where this course fits
Trimix qualification and specified logged experience are required; obtain the current standards and an instructor readiness assessment.
Ask about preparation dives, support logistics, rescue planning and how competence is assessed.
TDI Advanced Trimix Diver: learning scope
Entry & preparation
Trimix qualification and specified logged experience are required; obtain the current standards and an instructor readiness assessment.
What you study
Extend mixed-gas technical competence for divers who already have substantial relevant experience.
- Advanced gas and exposure planning
- Multiple contingencies
- Team execution for demanding profiles
Qualification boundary
This is not a general permission to dive any depth or environment. Qualification limits and individual readiness still apply.
A visual summary of this independent course guide. Confirm current prerequisites and standards with the agency and instructor.
What the training focuses on
| Learning area | Discuss before booking |
|---|---|
| Advanced gas and exposure planning | How will this be taught and assessed? |
| Multiple contingencies | What preparation and equipment should I bring? |
| Team execution for demanding profiles | What happens if I need more practice? |
Understand the qualification’s scope
This is not a general permission to dive any depth or environment. Qualification limits and individual readiness still apply.
Frequently asked questions
Is this the natural next course immediately after Trimix?
Not necessarily. Relevant experience and consistent performance between courses are important.
Can some gases be unsuitable at the surface?
Yes. Advanced gas handling requires specialist procedures; do not use unidentified or unfamiliar mixtures.
Does completion mean I can enter deep caves?
No. Depth and overhead qualifications are separate, and combined activities require suitable competence.
What should an Australian course quote include?
Ask for an itemised total covering learning materials, practical sessions, certification, equipment, boat or site fees and any extra training. Availability, duration and prices are centre-specific.
Where do I confirm the latest prerequisites?
Use the official TDI information linked below and ask the authorised instructor to check your certification, age, experience, medical and first-aid records. A similar course name from another agency is not automatic equivalence.
Official course information
TDI: Advanced Trimix Diver ↗Agency standards determine certification requirements. This guide does not reproduce the full standard or imply agency endorsement.