Trimix

Are you looking to expand your depth range? Do you want to reduce narcosis during deep dives? The TDI Trimix Diver Course could be your next step! As your motivation to explore progresses, you will find that you may want to go deeper to dive that wreck that is part of history or that cave system that you have read so much about. One of the major limiting factors of going deeper is narcosis; TDI’s Trimix Diver course shows how to minimize the effects of narcosis by adding helium to offset the nitrogen in your breathing gas. While taking the Trimix Diver course your TDI Instructor will teach you how to plan and execute dives utilizing as little as 18 percent oxygen and diving to maximum depth of 60 metres/200 feet with a blend of helium appropriate for the planned depth.

What you can expect to learn

• Advanced decompression dive planning including:
  • Gas planning based on equivalent narcotic depths, nitrogen and helium absorption and elimination, CNS and OUT limits, Isobaric Counter diffusion, volume requirements, etc.
  • Decompression gas choices
  • Tables vs. 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 nitrox and mixes, and gas blending procedures

Course Equipment Requirements

The following equipment is required for each student:

• Bottom mix cylinder(s)
  • Cylinder volume appropriate to complete all planned decompression on bottom mix b. Dual outlet valve, double manifold or independent doubles c. Labeled in accordance with TDI Standards 2. Decompression mix cylinder(s) a. Cylinder volume should contain a minimum of 1.5 times the gas required for the planned decompression b. Labeled in accordance with TDI Standards 3. Suit inflation cylinder, required for dry suit divers only 4. Regulators a. Primary and primary redundant required on all bottom mix cylinder(s) b. Submersible pressure gauges are required on all primary/bottom mix cylinders c. A contingency use long hose second stage should be designated and appropriately rigged to facilitate air sharing at depth if necessary d. It is strongly recommended that the 3 required regulators be all DIN or all yoke 5. Buoyancy compensator device(s) (BCD) adequate for equipment configuration 6. Redundant depth and timing devices 7. Air decompression computers are allowed for use as depth and timing devices, provided they have a gauge mode 8. Redundant light system if required by site

Course Prerequisites

• Minimum age 18
• Minimum certification of TDI Advanced Nitrox AND Decompression Procedures Diver, or equivalent
• Proof of 100 logged dives