SSI Extended Range eLearning

SSI Extended Range — eLearning & Certification Credit Only

Take your diving deeper with the SSI Extended Range programme — your introduction to technical diving on open circuit. This course teaches you how to plan and conduct dives using air, nitrox, or trimix with staged decompression to a maximum depth of 45 metres (148 feet). This product provides your academic training and certification credit only; all in-water training and assessments must be booked separately with an authorised SSI Extended Range Instructor.

What you’ll learn online

• SSI Extended Range diving philosophy and training structure
• Advanced gas management and decompression planning
• Equipment setup for twinset or sidemount configurations
• Gas-switching and stage cylinder handling procedures
• Failure prevention, risk management, and redundancy principles
• Team awareness, communication, and emergency coordination
• Ascent management, buoyancy control, and decompression protocols
• Environmental and physiological considerations for deeper diving

Required practical training (booked separately)

To complete your certification, you’ll need to undertake in-water training dives with an authorised SSI Extended Range Instructor. The practical programme typically includes:

• Progressive deep dives with staged decompression up to 45 metres
• Simulated gas failures, equipment malfunction, and problem-solving drills
• Stage cylinder rigging, gas analysis, and gas-switch practice
• Ascent planning and decompression stop management
• Emergency procedures and team-based gas-sharing exercises
• Buoyancy and propulsion refinement for precise control at depth

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

Important prerequisites

• You must be at least 18 years old and certified as an SSI Deep Diver and Enriched Air Nitrox Diver (or equivalent).
• A minimum of 50 logged dives is required before beginning practical training, including recent deep and nitrox dives.
• You must hold valid first aid, CPR, and oxygen administration certifications (within 24 months) and a current diving medical signed by a physician.
• Divers must use an approved twinset or sidemount configuration meeting SSI Extended Range equipment standards.
• Confirm that the dive centre you intend to use offers SSI Extended Range training and has access to appropriate deep-water training sites.

Free registration

To start your training, register for a free SSI account and affiliate with our dive centre here:
Register with Dorset Diving.

What’s next?

Once you’ve completed SSI Extended Range, you’ll be qualified to conduct staged decompression dives using twinset or sidemount systems. Many divers continue on to Technical Extended Range or Hypoxic Trimix training to explore even deeper and more complex dive environments.