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Want to dive deeper and reduce narcosis? The TDI Trimix Diver Course is your next step! As you advance in diving, you'll likely want to explore historical wrecks or intricate cave systems at greater depths. One major challenge of deeper dives is narcosis; the TDI Trimix Diver course teaches how to mitigate narcosis by adding helium to your breathing gas. In this course, your TDI Instructor will guide you on planning and executing dives with as little as 18% oxygen, reaching depths of up to 60 meters/200 feet using appropriate helium blends.

Who this course is for:

  • Certified Advanced Nitrox and Decompression Procedures divers aiming to:

    • Extend their depth range

    • Minimize narcosis during deep dives

    • Enhance their technical diving skills

Course prerequisites:

  • Minimum age of 18

  • Certification as a TDI Advanced Nitrox AND Decompression Procedures Diver, or equivalent

  • Proof of 100 logged dives

What you can expect to learn:

  • The course covers advanced decompression dive planning, including:

  • Gas planning based on equivalent narcotic depths, nitrogen and helium absorption, CNS and OUT limits, Isobaric Counter Diffusion, volume requirements, etc.

  • Decompression gas choices

  • Use of dive tables versus personal dive computers

  • Emergency and contingency planning (equipment failure, omitted decompression, etc.)

  • Decompression diving procedures

  • Equipment selection

  • Pre-dive checks and drills

  • Stress analysis and mitigation

  • Following a decompression schedule

  • Gas switching

  • Team awareness and communication

  • SMB/lift bag deployment

  • Proper trim, buoyancy, and finning techniques

  • Management of multiple decompression/stage cylinders

  • Emergency procedures (equipment failures, catastrophic gas loss, omitted decompression, navigational errors, injured/unconscious diver, etc.)

  • Equipment considerations, cylinder labeling, analyzing trimix and nitrox mixes, and gas blending procedures

What’s in it for you?

  • Ability to perform technical dives using custom trimix mixtures without direct supervision, provided:

  • The diving activities match those of training

  • The dive locations match those of training

  • The environmental conditions match those of training

  • Eligibility to enroll in TDI Advanced Wreck and TDI Advanced Trimix courses

TDI Trimix Diver minimum certification requirements:

  • Pass the TDI Trimix Diver course written exam

  • Complete all open water requirements safely and efficiently

  • Exhibit mature, sound judgment in dive planning and execution

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