Advanced Trimix

The TDI Advanced Trimix Diver Course is the top level of training for open circuit divers wishing to dive to depths as deep as 100 metres/330 feet utilizing hypoxic levels of oxygen (below 17 percent). This course is perhaps one of the most informative and challenging of all of the TDI open circuit courses. Upon completion, you will be among some of the most elite divers, capable of doing and seeing more while diving than any other divers out there.

What you can expect to learn

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 OTU limits, isobaric counter diffusion, volume requirements, etc.
  • Use of hypoxic gasses
  • HPNS and isobaric counter diffusion
  • 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 fining techniques
• Management of multiple (minimum of 3) 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 for planned dive and student gas consumption
  • Dual outlet valve, double manifold or independent doubles
  • Labeled in accordance with TDI Standards
• Travel mix cylinder(s)
  • Cylinder volume appropriate for planned dive and student gas consumption
  • Labeled in accordance with TDI Standards
• Decompression mix cylinder(s)
  • Cylinder volume appropriate for planned dive and student gas consumption
  • Labeled in accordance with TDI Standards
• Suit inflation cylinder, required for dry suit divers only
• Regulators
  • Primary and primary redundant required on all bottom mix cylinder(s)
  • Submersible pressure gauges are required on all primary bottom mix cylinders
  • A contingency use long hose second stage should be designated and appropriately rigged to facilitate air sharing at depth if necessary
  • It is strongly recommended that all 4 required regulators be all DIN or all 4 yoke Buoyancy compensator device(s) (BCD) adequate for equipment configuration
• Redundant depth and timing devices; air decompression computers allowed for use as depth and timing devices
• Redundant light system if required by site
• Ascent reel with lift bag/surface marker buoy
  • Adequate for maximum planned depth
  • Adequate lift and size for the dive environment
• Exposure suit adequate for the open water environment
• Line cutting device
• Underwater slate, for decompression / contingency tables
• Helium analyzer, recommended

Course Prerequisites

• Minimum age 18
• Minimum certification of TDI Extended Range or Trimix Diver or equivalent
• Show proof of 100 logged dives, 25 must be deeper than 30metres/100feet
• Provide proof of prior logged experience w/ double cylinders and any other unfamiliar equipment such as a dry suit