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Extended Range Diver

Certain areas of the world provide spectacular dives at depths deeper than 39m/130 feet but you will 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 55m/180 feet you won’t have to miss those dives. The Extended Range course will cover topics and skills such as

- Equipment requirements and configuration
- Decompression options
- Use of surface marker buoys
- Buddy rescue
- Narcosis checks and management

Materials for this course include the TDI Extended Range Diving Manual and the US Navy or Buhlmann Air Decompression Tables (made of vinyl for easy in-water use and storage)


  • Minimum age 18
  • Certified as a TDI Advanced Nitrox Diver and TDI Decompression Procedures Diver, or equivalents
  • Provide proof of a minimum of 100 logged dives, of which 25 must be deeper than 30 metres / 100 feet

Course Materials
  • TDI Extended Range Entry Level Trimix Diver Manual

Equipment Needed
  • Due to the wide range of configurations that can be used we work with each individual to insure each person has the proper equipment rather you are doing the training on a rebreather or open circuit.


What's Your Next Adventure
After achieving the this level of certification, you will want to enhance your skills and knowledge. Check out: Entry Level Trimix
Contact Us
  •  (703) 369-0098
  •  6884 Wellington Rd
       Manassas, VA 20109
  •  Mon: 12-7| Tues/Wed: Closed   Thur/Fri: 12-7 | Sat:12-6 | Sun:12-5