TDI Extended Range

Certain areas of the world provide spectacular dives at depths deeper than 39 metres/130 feet but you may not have access (or very limited access) to helium. The TDI Extended Range course teaches you the proper techniques for utilizing compressed air as a breathing gas, and with a maximum depth of 55 metres/180 feet, so you don’t have to miss those dives! 

The TDI Extended Range Diver Course provides the training and experience necessary including proper techniques, equipment requirements, and hazards of deep air diving, to competently utilize air for dives up to 55 metres/180 feet that require staged decompression, using nitrox mixtures or oxygen during decompression.

The Training

The TDI Decompression Procedures Course includes three parts:

  • Online learning – once you have signed up for the course, we will provide you a code to sign up for the online learning in advance of your practical training to work through at home. You will then go through key areas in greater detail with your instructor and cover areas such as plus many others:
    • Hypoxia 
    • Decompression options 
    • Team planning
    • Technical dive support
  • Classroom training – After you have reviewed the key knowledge areas and ready to go you will then join your instructor for the practical element of your training and cover the following areas:
    • Generating decompression plans using computer software
    • Creating contingency dive schedules in the event of an emergency
    • Equipment checks and labelling prior to a technical dive
    • Use of START acronym to begin a dive
  • Open Water Training – After you have covered the key knowledge through the online learning, you will then join your instructor for 4 open water dives where you will cover the following plus much more:
    • Lift bag deployment as back-up buoyancy
    • Demonstrate ability to confirm gas switches at depth with buddy/team members
    • Demonstrate competence managing 2 stage cylinders
    • Gas matching procedures


  • Age: 18 years old and above
  • TDI Advanced Nitrox Diver and TDI Decompression Procedures Diver ,or equivalent, from an alternative agency
  • Minimum of 100 logged dives, of which 25 must be deeper than 30 metres
  • Good physical health – You will need to fill out a self certification medical statement. If you have any medical conditions you think may prevent you from scuba diving please feel free to contact us




  • Online learning materials + certification
  • Gases + cylinders
  • 4 Open Water Dives
  • Transport to and from dive sites
  • 10% off Aqualung + APEKS dive accessories

Time commitment 

2 days