If you’ve ever heard a diver say “I did a deep dive today,” you might have pictured a descent into the dark blue. In reality, what counts as deep diving is simpler and more specific than most people expect. It’s not about how brave you are or how far you can see into the blue. It’s a defined depth range with its own risks, skills and training.
At Ocean Tribe in Diani Beach, we get this question from new divers all the time. Here’s a clear breakdown.
So, What Counts as Deep Diving?
In recreational scuba, any dive deeper than 18 metres (60 feet) is considered a deep dive. The recreational limit is 40 metres (130 feet). Below that, you’re in technical diving territory, which needs different training and equipment.
| Depth | Category |
|---|---|
| 0 to 18 m (0 to 60 ft) | Standard Open Water Licence |
| 18 to 30 m (60 to 100 ft) | Deep diving (with Advanced training) |
| 30 to 40 m (100 to 130 ft) | Deep diving (with Deep Diving Specialty) |
| Beyond 40 m (130 ft) | Technical diving |
The 18 metre line matters because that’s the maximum depth for a newly certified SSI Open Water Diver. Cross it, and the physics start working against you.
Why Does 18 Metres Matter?
Depth changes how your body and your equipment behave. Once you pass 18 metres, several things happen at once.
You use your air much faster. Pressure increases with depth, so every breath contains more gas. At 30 metres, you’re breathing air four times as dense as at the surface. A tank that lasts an hour in the shallows can be gone in a fraction of that time.
Your no-decompression limits shrink. The deeper you go, the less time you can stay before you need to ascend. A deep dive has a much shorter bottom time, so planning matters more.
Nitrogen narcosis becomes a real factor. Often called “the martinis,” this is a mild intoxication from breathing nitrogen under pressure. It can affect judgement, coordination and reaction time. It varies from diver to diver and from day to day, which is exactly why training matters.
Colours and light change. Reds disappear first, and light levels drop. Deep sites can feel dim and surprisingly cold.
Emergencies are harder to manage. Surfacing isn’t instant. Ascending safely takes time, so there’s less margin for error if something goes wrong.
Depth Limits by SSI Certification Level
Your certification level sets how deep you’re trained to dive:
- SSI Open Water Diver: up to 18 metres. This is your starting point, and it’s the maximum depth before deep diving begins.
- SSI Advanced Adventurer: up to 30 metres. You complete a range of Adventure Dives, including a deep dive, to build experience and confidence.
- SSI Deep Diving Specialty: up to 40 metres. This is the course for divers who want to explore the full recreational range with proper planning and skills.
- Technical diving (SSI Extended Range): beyond 40 metres. This is a separate training path with specialised equipment, gas planning and procedures.
Stay within your training limits. A certification isn’t just paperwork. It tells you what you’ve practised and what you’re prepared for.
What You Learn in a Deep Diving Course
The SSI Deep Diving Specialty isn’t about chasing numbers. It’s about doing deep dives sensibly. You’ll cover:
- Planning dives with air consumption, no-decompression limits and turn pressures in mind
- Recognising and managing nitrogen narcosis
- Buoyancy control and monitoring your gauges at depth
- Safe descent and ascent techniques, including safety stops
- Managing gas reserves and working as a buddy team
- Emergency procedures specific to deeper water
Good deep divers aren’t the ones who go the deepest. They’re the ones who plan carefully, stay calm and always have a margin built in.
Is Deep Diving Safe?
Deep diving carries more risk than shallow diving, but with proper training, planning and discipline, it’s well within reach of most healthy divers. The risks come from skipping the fundamentals: poor planning, diving beyond your training, rushing the ascent, or ignoring your gauges.
A few habits keep deep dives safe:
- Plan the dive and dive the plan.
- Keep a conservative air reserve and turn the dive early.
- Ascend slowly and always do your safety stop.
- Stay close to your buddy and communicate.
- Stop and ascend if you feel unwell, overly euphoric or confused.
Who Should Consider Deep Diving?
Deep diving is a natural next step if you:
- Hold an Open Water certification and want to go further
- Have completed your Advanced Open Water and want to explore beyond 30 metres
- Want to dive wrecks and walls that sit below 18 metres
- Are working towards a professional level. Deep diving is a core skill for SSI Divemasters and Instructors.
You don’t need to rush. Build your experience in the shallower range first, get comfortable with your buoyancy and gas consumption, and then add depth.
Learn to Dive Deep with Ocean Tribe
Ocean Tribe is a registered SSI Diamond Instructor Training Centre at The 41 Beach Club on Diani Beach, Kenya. Our small dive groups and experienced instructors mean you get proper attention while you build your skills, whether you’re taking your first step beyond 18 metres or preparing for a professional career in diving.
Ready to find out what deep diving is really like? Book your dive online and enjoy a $10 online discount, or get in touch to talk through the right course for your level.
Frequently Asked Questions
What counts as deep diving in scuba?
Any dive deeper than 18 metres (60 feet) is a deep dive. The maximum recreational depth is 40 metres (130 feet).
How deep can an Open Water Diver go?
An SSI Open Water Diver is certified to 18 metres.
How deep can I go with Advanced Adventurer?
SSI Advanced Adventurer certification qualifies you to dive to 30 metres.
Do I need a special course to dive to 40 metres?
Yes. The SSI Deep Diving Specialty trains you to dive to the 40 metre recreational limit.
What is nitrogen narcosis?
It’s a state of reduced judgement and coordination caused by breathing nitrogen under pressure at depth. It’s reversible, and ascending to shallower water clears it.
