Ready to explore beyond the 18-metre limit of your Open Water certification?
The SSI Deep Diving Specialty is designed to give you the knowledge, skills and confidence to safely dive to the recreational limit of 40 metres. Over three training dives and a comprehensive academic programme, you’ll learn how to plan, prepare and conduct deep dives while understanding the additional considerations that come with increased depth.
Many of Koh Tao’s most exciting dive sites reveal their best features below 18 metres. Dramatic granite pinnacles, deeper swim-throughs, larger schools of fish and occasional pelagic encounters all become more accessible with the right training.
At Funky Turtle Divers, we don’t just teach you to dive deeper—we teach you to become a safer, more confident and more capable diver.
2 Day | 3 Dives | 6,800 THB
1 Day | 2 Dives | 5,300 THB (Deep specialty after Advanced Course)
SSI Deep Diving Specialty at a Glance
Duration: 2 days Minimum age: 15 years Prerequisites: SSI Open Water Diver (or equivalent) Open Water Training Dives: 3 Maximum Training Depth: 40 metres Certification: SSI Deep Diving Specialty Location: Koh Tao, Thailand Price: 6,800
What Is the SSI Deep Diving Specialty?
The SSI Deep Diving Specialty builds on the skills you learned during your Open Water course and prepares you for recreational diving between 18 and 40 metres.
As depth increases, so do the challenges. Air is consumed more quickly, no-decompression limits become shorter, buoyancy changes become more noticeable and the effects of pressure become increasingly important.
Throughout the course, you’ll learn how to safely manage these factors through proper planning, equipment preparation and in-water experience.
By the end of the programme, you’ll be certified to dive to a maximum depth of 40 metres with an equally qualified buddy.
What Will You Learn?
The course combines classroom learning with practical application over three open water dives.
You’ll learn how to:
- Plan and conduct deep dives safely.
- Understand the effects of pressure at depth.
- Manage increased gas consumption.
- Monitor no-decompression limits.
- Recognise and manage nitrogen narcosis.
- Improve buoyancy and trim at depth.
- Perform controlled descents and ascents.
- Conduct effective safety stops.
- Dive safely with a buddy.
- Respond appropriately to common deep diving situations.
The emphasis is always on understanding why these skills are important – not simply completing the dives.
Understanding Nitrogen Narcosis
One of the most important topics covered during the course is nitrogen narcosis.
As pressure increases, nitrogen can affect your judgement, coordination and reaction times. Every diver experiences narcosis differently, and understanding its effects is an important part of becoming a safe deep diver.
During the course you’ll learn:
- What causes narcosis.
- How to recognise the symptoms.
- Why different divers experience it differently.
- How to minimise its effects.
- When to end a dive if symptoms occur.
Understanding narcosis allows you to make better decisions whenever you dive deeper.
Gas Management
One of the biggest changes you’ll notice during a deep dive is how much faster you consume your breathing gas.
At 40 metres you’ll breathe approximately five times as much gas as you would on the surface.
Throughout the course you’ll develop good gas management habits, including:
- Estimating gas requirements.
- Planning reserve pressures.
- Monitoring air consumption throughout the dive.
- Understanding turn pressures.
- Always maintaining an appropriate gas reserve.
These skills are valuable on every dive, not just deep dives.
Buoyancy and Dive Control
As depth increases, precise buoyancy control becomes even more important.
You’ll continue developing the skills to:
- Maintain neutral buoyancy.
- Descend and ascend in a controlled manner.
- Maintain good trim.
- Control your breathing.
- Avoid rapid ascents.
- Complete accurate safety stops.
Strong buoyancy control helps reduce stress, improve air consumption and make every dive more enjoyable.
Equipment for Deep Diving
You’ll also learn about the equipment commonly used for recreational deep diving.
Topics include:
- Dive computers.
- DSMBs and reels.
- Torches.
- Exposure protection.
- Surface signalling equipment.
- Air-integrated computers.
- Backup equipment.
Understanding your equipment helps you prepare properly for every deep dive.
Where Will We Dive?
Koh Tao offers several excellent sites for deep diving training.
Depending on conditions, your dives may take place at locations such as:
- Chumphon Pinnacle
- Southwest Pinnacle
- Shark Island
- Green Rock
- White Rock
We always select dive sites based on sea conditions, visibility and student experience to provide the safest and most enjoyable learning environment.
How Long Does the Course Take?
The SSI Deep Diving Specialty is normally completed over two days.
Your course includes:
- SSI digital learning.
- Academic review with your instructor.
- Equipment preparation.
- Three open water training dives.
- Practical skill development.
- Debriefs after every dive.
By the end of the course you’ll have both the theoretical knowledge and practical experience needed to dive safely to 40 metres.
Is the Deep Diving Specialty Difficult?
Not particularly – but it does require good diving habits and a willingness to learn.
If you’re comfortable with the skills from your Open Water course, your instructor will gradually build your confidence throughout the programme.
The course is designed to challenge you without overwhelming you, allowing you to develop your skills progressively over multiple dives.
Who Should Take This Course?
The Deep Diving Specialty is ideal for divers who:
- Want to dive deeper than 18 metres.
- Enjoy exploring pinnacles and walls.
- Are interested in wreck diving.
- Want to improve their dive planning.
- Want to build confidence before progressing further.
- Simply want to become a better diver.
Many divers choose Deep Diving as one of their first specialty courses after Open Water.
Should I Complete Advanced Open Water First?
This is one of the questions we’re asked most often.
The answer is not necessarily.
If you already know you’re interested in deep diving, we generally recommend completing the Deep Diving Specialty first.
The reason is simple. The Deep Diving Specialty is dedicated entirely to deep diving, giving you the opportunity to complete the full academic programme, learn the theory in detail and complete three training dives focused solely on developing your deep diving skills.
By comparison, Advanced Open Water introduces you to a range of different diving activities. It’s a fantastic course if you’re still deciding what interests you most, as it allows you to experience several different types of diving before choosing which specialties to pursue.
If you’ve already decided that deep diving is what excites you, completing the full Deep Diving Specialty first will give you a more comprehensive understanding of the subject.
Whichever path you choose, every SSI Specialty you complete also counts towards your SSI recognition levels:
- Specialty Diver – 2 specialty certifications and 12 logged dives.
- Advanced Open Water Diver – 4 specialty certifications and 24 logged dives.
- Master Diver – 5 specialty certifications (including Deep and Navigation) and 50 logged dives.
Why Complete Your Deep Diving Specialty in Koh Tao?
Koh Tao is one of Thailand’s best destinations for deep diving training.
The island offers:
- Warm water all year round.
- Excellent visibility.
- Short boat journeys.
- A variety of deep dive sites.
- Experienced SSI instructors.
- Easy progression onto further specialty courses.
It’s the perfect place to gain confidence before taking your new certification around the world.
Why Choose Funky Turtle Divers?
At Funky Turtle Divers, we believe understanding creates confident divers.
Rather than simply taking you to 40 metres, we’ll help you understand how to dive safely, comfortably and confidently at depth.
You’ll benefit from:
- Small training groups.
- Experienced SSI instructors.
- Plenty of time to practise your skills.
- Thorough academic sessions.
- Personalised coaching.
- A relaxed and supportive learning environment.
Our goal is simple – help you become the kind of diver your buddies trust.
What Comes Next?
Once you’ve completed your Deep Diving Specialty, there are plenty of exciting ways to continue your diving journey.
Popular next steps include:
- Enriched Air Nitrox – Extend your no-decompression limits and make repetitive and deeper dives more enjoyable.
- Wreck Diving – Explore wrecks safely and confidently.
- Perfect Buoyancy – Fine-tune your trim and control underwater.
- Stress & Rescue – Become a more aware, confident and capable buddy.
- Continue building your experience towards SSI Advanced Open Water Diver and eventually Master Diver recognition.
2 Day | 3 Dives | 6,800 THB
1 Day | 2 Dives | 5,300 THB (Deep specialty after Advanced Course)
Book Your SSI Deep Diving Specialty in Koh Tao
If you’re ready to explore deeper dive sites and develop the skills to dive safely to 40 metres, we’d love to help.
Join us at Funky Turtle Divers and discover why the Deep Diving Specialty is one of the most rewarding and useful courses you’ll ever complete.
Dive deeper. Dive smarter. Stay funky.
