TDI Helitrox Instructor

The TDI Helitrox Instructor course provides the training required to competently teach the methods and procedures for planned stage decompression diving utilizing Helium in the breathing mixture. The objective of this course is to train TDI Helitrox Instructors how to teach standard staged decompression diving not exceeding a maximum depth of 45m. Enriched air nitrox (EAN) and Helium mixes with no greater than 35% He content, and up to 100% oxygen for decompression diving are permitted. Breathing gas mixtures containing more than 35% Helium (+/- 5%) or less than 21% oxygen are not permitted (+/- 1%).

Prerequisites TDI Helitrox Instructor :
  • Min. 21 years old
  • Min. TDI Advanced Nitrox Instructor or equivalent
  • Min. TDI Trimix diver or equivalent
  • proof of 250 logged dives with a minimum of 20 logged Helitrox or Trimix decompression dives outside of training, 10 of these dives must be in the last 12 months
  • Proof of 10 certified Advanced Nitrox or Deep or Advanced Adventure divers or equivalent


  • Dives: 4 decompression dives
  • Total bottom time: 100min
  • All dives must be deeper than 30m
  • 2 dives must be deeper than 40m
  • Min. number of classroom and briefing hours is 8

Note: All dives must contain Helium mixtures with contents consistent with course parameters

To complete this course,
students must:

  • Satisfactorily complete the TDI Decompression Procedures Course written examination
  • Satisfactorily complete the TDI Trimix course written examination and be able to adequately explain each answer to a prospective student
  • Complete all open water requirements safely and efficiently
  • Demonstrate mature, sound judgment concerning dive planning and execution
  • Demonstrate proficiency in teaching the TDI Helitrox Diver course
  • Present at least 1 graded presentation on a Helium topic