While using helium-based breathing gases, the TDI Trimix Instructor Course delivers the training required to teach trimix diving that requires staged decompression. Utilizing gases containing no less than 18% oxygen, candidates will complete the four required dives up to 60 metres/200 feet. Topics that candidates may be asked to present include:

  • Hypoxia
  • Nitrogen narcosis
  • Helium absorption and elimination
  • Counter diffusion
  • Dive planning
  • Gas switching procedures


The TDI Trimix Instructor materials includes

  • Extended Range/Trimix instructor guide
  • Extended Range/Trimix PowerPoint®
  • EAD table
  • TDI student record folder
  • Logo sticker
  • TDI Extended Range/Trimix manual
  • TDI presentation bag
  • TDI temporary card