SSI Hypoxic Trimix eLearning

SSI Hypoxic Trimix Diving — eLearning & Certification Credit Only

Push your limits and explore the depths beyond 60 metres with the SSI Hypoxic Trimix Diving programme. This course represents the highest level of open-circuit technical training, preparing you to safely plan and conduct deep, staged decompression dives using hypoxic trimix gas blends. This product includes your academic training and certification credit only; all practical dives and assessments must be booked separately with an authorised SSI Extended Range Instructor Trainer.

What you’ll learn online

• Advanced dive physics, physiology, and decompression theory for extreme depths
• Hypoxic gas principles, blending, and analysis techniques
• Advanced equipment configuration and redundancy management
• Decompression planning and ascent profile management for deep trimix dives
• Multi-stage and multi-gas switching procedures
• Team awareness, mission planning, and emergency coordination
• Failure management, bailout strategies, and emergency decompression
• Environmental considerations and risk management for deep technical diving

Required practical training (booked separately)

To earn your certification, you must complete the in-water training dives with an authorised SSI Extended Range Instructor Trainer. The practical training component typically includes:

• Progressive deep trimix dives to depths of up to 100 metres (330 feet)
• Complex decompression procedures and multi-gas switches
• Stage cylinder handling, failure management, and emergency ascents
• Simulated equipment failures, gas loss, and problem-solving at depth
• Advanced dive planning and execution for long-duration technical dives

These sessions are not included with this eLearning product and must be arranged separately with Dorset Diving or another SSI Extended Range Dive Centre that offers the Hypoxic Trimix programme.

Important prerequisites

• You must be at least 18 years old and certified as an SSI Technical Extended Range Diver (or equivalent).
• A minimum of 100 logged dives, including extensive deep and decompression experience, is required before practical training.
• Valid first aid, CPR, and oxygen administration certifications (within 24 months) and a current diving medical signed by a physician are mandatory.
• Divers must use an approved twinset or sidemount configuration meeting SSI Extended Range standards, with all required redundancy systems.
• Before booking, confirm that your chosen dive centre offers SSI Hypoxic Trimix training and has access to suitable deep-water environments.

Free registration

Begin your learning journey by creating a free SSI account and affiliating with our dive centre here:
Register with Dorset Diving.

What’s next?

After achieving your SSI Hypoxic Trimix certification, you’ll be among the elite few qualified to dive to 100 metres on open circuit. Many divers continue into CCR Hypoxic Trimix or professional-level technical instruction, expanding their capabilities into expedition and exploration diving.