Key Points
- Recreational scuba diving typically involves depths of up to 40 metres (130 feet), while deeper dives beyond 40 metres require technical diving certifications. These limitations will be set by your level of certification achieved in training.
- At great depths, the pressure of the water increases dramatically, which can lead to serious health risks from decompression sickness (DCS) if safety protocols aren’t followed precisely. Divers must also consider nitrogen narcosis, a condition induced by breathing high-pressure oxygen at deep-sea levels that can lead to loss of motor control and disorientation.
- Divers should never attempt to go beyond their limits; having realistic expectations about what you can handle based on training and experience is essential for ensuring your safety when exploring deeper waters via scuba diving.
Introduction
When scuba diving, we get a glimpse at an unseen world. This world changes the deeper we go, with many different creatures and plants to explore. We can witness a wide array of coral, fish and other sea life we may never have encountered before. We have an unparalleled chance at sights that are simply breathtaking. But just how deep can we go?
How deep is possible is a matter of record, with the world’s deepest dive standing at 332.35 metres (1,090 feet), being set by Ahmed Gabr in 2014. However, an astonishing feat such as this is beyond most of our abilities, and you’re probably wondering what the real limits are for most divers. This is something you should know not only to keep your dives enjoyable but for safety reasons.
In this article, we’ll look at recreational and deep-sea diving limits. We’ll look at how the changes in pressure affect the body and why it’s essential that you only dive to the limits defined by your training. We’ll also look at some consequences of diving too deep and introduce you to AGULHAS, where you can get scuba diving gear made with safety, sustainability and quality in mind. Let’s get started!
Recreational Diving vs Deep Sea Diving

Before discussing the limitations on depth, it’s important to know the differences between recreational scuba diving and deep-sea diving.
Scuba diving allows divers to experience various marine life and explore the ocean’s depths in a safe and controlled environment. Recreational scuba diving differs from deep-sea diving, as it usually does not involve extreme depths or specialised equipment. Recreational scuba divers will not exceed 40 metres (130 feet).
The benefits of this kind of scuba diving are numerous. It is a great way to experience nature at its fullest – from breathtaking reefs to incredible shipwrecks – while providing physical health benefits such as improved cardiovascular system health and increased muscular strength. Additionally, it is an excellent relaxation method and can provide psychological benefits such as reducing anxiety and stress levels.
On the other hand, deep-sea diving is a type of scuba diving that takes you further into the ocean depths. This type of diving usually involves going deeper than 40 metres and reaching depths as great as 100 metres (330 feet). Divers are not recommended to go beyond this depth due to the risk of decompression sickness.
Deep-sea diving is often done for science or exploration, where divers can encounter different types of marine life they may not find in recreational scuba dives. However, the added depth promises new experiences, wildlife and solitude for those who try deep-sea diving for pleasure.
How Safe Limits Are Set
Diving agencies such as PADI and SSI have specific training programs designed to teach divers the skills and knowledge necessary to dive safely to certain depths. These training programs are structured to progressively increase complexity and depth as the diver gains experience and skills. As a result, divers are certified only for specific levels of diving and are only authorised to dive to certain depths based on their certification level.
For example, the PADI Open Water Diver certification is a basic level of certification. It typically allows a diver to dive to a maximum depth of 12 metres (40 feet). However, more advanced certifications, such as the Advanced Open Water Diver, allow divers to dive deeper to depths up to 30 metres (100 feet).
Certification agencies set these diving limits based on factors such as the equipment used, the environment and the risks associated with diving at different depths. Certification agencies also have specific protocols for handling emergencies, which vary based on the certification level of the divers involved. It should be noted that different agencies have different rules, with PADI considering anything between 18 to 30 metres as a “deep dive”.
When presenting their certification, divers are expected to follow the diving limits and protocols associated with their certification level. This is important for their safety, the safety of other divers and the environment. In some cases, divers may be required to demonstrate their skills and knowledge before being allowed to dive to certain depths or to participate in certain types of dives, such as a wreck or cave diving.
The Depth Limit for Scuba Diving Explained

As highlighted, the certification agencies set safe limits for scuba diving. They are designed to ensure the safety of the divers and minimise the risk of decompression sickness. If you head over to the websites of PADI, SSI and other agencies, you’ll see that there are related training courses to bring you up to each level.
Let’s take a look at the recreational diving limits:
- Open Water Diver: The Open Water Diver certification course is the most popular scuba diving course worldwide. The recommended depth limit for open-water divers is 12 metres (40 feet). This depth provides ample opportunities to explore the underwater world without significant risks.
- Advanced Open Water Diver: This course is the next scuba diving certification level. The recommended depth limit for advanced open-water divers is 30 metres (100 feet). This depth allows divers to explore deeper wrecks and encounter larger marine life.
- Deep Diver Specialty Course: This speciality course is designed for divers who want to explore depths beyond the recreational diving limits. The depth limit for this course is 40 metres (130 feet), requiring advanced training and certification. Diving beyond this limit can be dangerous and should only be attempted by highly experienced and trained divers.
Beyond the recreational limits is technical diving, and these courses have different names, such as PADI’s Tec40 and the Extended Range program from SSI. Technical divers can explore depths beyond recreational diving limits and encounter more challenging environments. The depth limit for technical diving can vary depending on the diver’s experience, training and equipment. However, most technical diving organisations recommend a maximum depth of 60 metres (200 feet).
Effects of Pressure at Different Depths
As a scuba diver descends into the ocean, the pressure increases, and the body experiences various physiological effects. Understanding the effects of pressure is crucial in determining why the depth limits for scuba diving exist. Let’s take a closer look at the effects of pressure at different depths:
- 18 metres (60 feet): Pressure is approximately twice the atmospheric pressure of surface levels. The body experiences increased nitrogen absorption, and the air in the lungs compresses, reducing the volume. You may experience mild narcosis, which can affect judgement and coordination.
- 30 metres (100 feet): You should expect four times the atmospheric pressure at this depth over the surface. You will experience even further nitrogen absorption and possibly significant narcosis, impairing your judgement and motor skills.
- 40 metres (130 feet): At 40 metres, you will experience five times the atmospheric pressure. The body experiences significant nitrogen absorption, and there may be severe narcosis, which can cause hallucinations and confusion.
- 60 metres (200 feet): At this depth, the pressure is approximately eight times what you would experience on the surface. The body experiences extreme nitrogen absorption, and the risk of decompression sickness is high. The diver may also experience oxygen toxicity, which can cause convulsions, seizures and even death.
It’s essential to note that the effects of pressure can vary from person to person, and the depth limit for scuba diving should be determined based on individual factors such as training, equipment and health. Divers mustn’t become arrogant when it comes to depth. While you may be incredibly fit and strong, that does not mean you’re immune to the effects of pressure or different from other divers.
What Are the Dangers of Going beyond Diving Limits?

Diving too deep for your skill level can lead to various dangers threatening your safety and life. Here are some of the risks you may encounter:
- Decompression Sickness: If you dive too deep and stay underwater for too long, your body may absorb too much nitrogen, resulting in decompression sickness, also known as “the bends”. This condition can cause severe pain, paralysis and even death.
- Oxygen toxicity: Diving beyond safe limits can also expose you to high levels of oxygen, which can cause convulsions and other serious health problems. Oxygen toxicity occurs when the partial pressure of your oxygen reaches 1.4 atmospheres or greater.
- Equipment failure: Technical diving requires a specialised scuba diving kit that trained professionals must properly maintain and use. If you attempt to dive beyond your skill level, you may not be equipped to deal with equipment failures, which can be dangerous or even fatal. AGULHAS has a range of scuba diving gear produced with quality, safety and sustainability in mind. Plus, it’s within most budgets! Remember to look at our diving store and get the scuba diving kit you need for your next dive.
- Narcosis: Deep-sea diving can cause nitrogen narcosis and impaired cognitive function and judgement. This makes it difficult to make safe decisions or perform basic tasks.
- Depth-related injuries: As you descend to greater depths, the pressure on your body increases. This can lead to ear pain, sinus problems and other injuries that can be debilitating or even life-threatening.
To ensure safe diving, following the guidelines and recreational diving limits is essential. It’s also important to have proper scuba diving gear and to receive proper training and certification before attempting deep-sea diving or technical diving. Always dive within your safe limits and be aware of the dangers of diving beyond your skill level.
The Right Scuba Diving Equipment for Technical Diving
When diving to depths beyond 40 metres, it is crucial that you use the right scuba diving equipment. Deep-sea diving requires specialised gear such as technical dive computers, deep-water dive lights, alternative air supplies and rebreathers. Divers should also ensure they have a surface marker buoy and an alternate air source for emergencies.
Having the right scuba diving equipment can prevent accidents and ensure safety during technical and recreational diving. Divers should always check their gear before each dive and never venture into deeper waters without having the appropriate training and knowledge necessary for deep-sea dives. It is also important for divers to understand their capabilities and limitations when diving to stay within safe limits at all times.
Introducing AGULHAS
Here at AGULHAS, we know how important having safe scuba diving gear is. Those behind our brand include champion freediver Hanli Prinsloo, world champion swimmer Peter Marshall and acclaimed designer Alexander Taylor. All those involved know that it’s imperative for your safety and peace of mind that your scuba diving kit is made to the highest standards and that you have the right gear for your level and experience.
But it isn’t only safety that we pride ourselves on. All our scuba diving gear is designed with sustainability in mind. We’ve tried to ensure everything is made with sustainable materials across our diving range. This even extends to our packaging, which is biodegradable and compostable, meaning there’s no danger of it ending up as another pollutant in our precious oceans.
With AGULHAS, you can be sure that your scuba diving gear is the best. We are dedicated to the ethos of performance, innovation, functionality and sustainability. So why not check out the AGULHAS diving store and our range of scuba diving gear today?
Precautions for Diving Safely

Scuba diving can be a safe and enjoyable experience if proper precautions are taken. Here are some precautions to ensure you’re diving safely:
- Get Certified: Scuba diving is not a sport you can just jump into. Getting proper training and certification from a reputable scuba diving organisation is essential. The certification courses provide essential knowledge and skills required for safe scuba diving.
- Plan the Dive: Proper planning ensures you’re diving safely. The dive plan should include depth, time, equipment and environmental conditions. The diver should also have a backup plan in case of any unexpected situations.
- Check Equipment: Your scuba diving kit must be in good working condition and undergo regular maintenance checks. The equipment must also be rated for the depth and environmental conditions where it will be used.
- Monitor Depth and Time: The diver must regularly monitor their depth and time and follow the dive plan. Diving beyond the recommended limits can increase the risk of decompression sickness and other diving-related injuries.
- Breathe Properly: Proper breathing techniques are crucial for diving safely. The diver must breathe slowly and deeply and avoid holding their breath, which can cause lung overexpansion injuries.
- Stay Alert: The diver must always stay alert and be aware of their surroundings. They must avoid distractions and maintain a clear head to make quick and informed decisions in unexpected situations.
- Dive with a Buddy: Scuba diving should always be done with a buddy. The buddy system ensures that there is someone to assist in emergencies.
Diving safely is essential for any successful dive. By following the rules and regulations, you’re ensuring your well-being and those around you. Remember, no matter how good you become at scuba diving or how fit and healthy you are; the ocean must always be respected. It can be the most amazing environment on the planet and also the most dangerous. So, be safe and enjoy your dives!
Conclusion
Scuba diving can be enjoyed safely with the right equipment and proper precautions. There are dive limitations in place, and by becoming certified with well-known agencies such as PADI or SSI, you can become trained to achieve these depths. For those who wish to go beyond recreational diving limits, technical diving courses are available to gain the necessary skills and knowledge. The most important thing is to dive within your limits and ensure you have the right scuba diving equipment for your level and experience.
AGULHAS provides a range of quality scuba diving gear to ensure that you dive safely. So why not check out the rest of our website for more expertise and knowledge, and remember to visit our diving store to start exploring the wonders of deep-sea diving?
FAQs
Knowledge and practice can help overcome any phobia or anxiety related to depths in scuba diving. Learning about what happens at different levels underwater can give you comfort and confidence in exploring the depths safely. Additionally, slowly building up dive experiences by gradually increasing your depths on each dive can also help you get used to going deeper.
Planning a safe deep dive requires research into the area where you plan on diving, such as looking at weather reports, water temperature, etc. You should also be familiar with any certification requirements in advance as well as tackling personal fitness issues before the day of your dive. Moreover, have an appropriate backup plan prepared in case things don’t go according to plan underwater, such as an emergency ascent plan, and have a dive buddy to look out for you if any technical issues arise. Finally, never forget to stay within your safe limits when diving. It is key to know when it is time to surface, no matter how much deeper you want to go.
In addition to standard scuba diving equipment such as a buoyancy compensator, fins, mask, wetsuit and regulator, you will need additional equipment for deep-water diving. These include a dive computer, an underwater slate and a surface marker buoy (SMB) to signal the boat/shore in case of emergency or distress. It’s also vital to have an alternate air source like an octopus regulator or spare tank and, finally, one or two stages of decompression gas – typically nitrox, helium or oxygen – depending on the depth and duration of the dive. All this equipment is necessary for diving safely and should be checked before each dive.