What is the PADI Open Water Course Koh Tao

Learn all about the PADI Open Water Diving course

The PADI Open Water course is the most popular entry-level scuba diving certification in the world. Every year thousands of people take their first steps (or breaths) in the world of scuba diving by signing up for the PADI Open Water course. With more than 70% of the earth’s surface covered with water, it is not difficult to understand why.

Certification to 18 Metres

The PADI Open Water Diver course is the world’s most recognised entry-level scuba certification, qualifying you to dive independently with another certified diver to a maximum depth of 18 metres / 60 feet anywhere in the world. Throughout the PADI course, you will develop the essential knowledge, practical skills, and confidence needed to safely explore the underwater environment using scuba equipment. In this article, we will highlight everything you need to know about the course, including what to expect from your training and how we approach diver education at our dive centre.

Enrol on the Koh Tao PADI Open Water Diver course

One of the most surprising aspects of the PADI Open Water Diver course is that students can begin their scuba training from as young as 10 years old. Divers aged 10 and 11 are initially limited to a maximum depth of 12 metres, with this automatically increasing to 18 metres once they reach the age of 12. Students between the ages of 10 and 15 receive the Junior Open Water Diver certification before transitioning to the standard Open Water certification as they get older.

In recent years, scuba diving has become an increasingly popular activity for families travelling together, offering a unique opportunity to learn new skills, build confidence, and experience the underwater world side by side. For families who are not yet certified divers, completing the course together can become a memorable and rewarding part of any holiday. To enrol on the course, participants simply need to demonstrate basic swimming abilities and feel comfortable in the water.

Medical Questionnaire

Another prerequisite for enrolment on the course is that you need to be medically fit for scuba diving. When you contact our team to book a course, they will send you a diving medical questionnaire to have a read through.

This is to check that there are no pre-existing medical conditions that would prevent you from scuba diving. The main part of the medical consists of 10 yes or no questions and if all the answers are ‘NO’ that means you are fit to dive. If you answer ‘YES’ to any of the questions on page one, you will be asked to answer some additional questions on page 2 and based on that, the approval of a physician may be required before starting the course. You can find the medical questionnaire here on our website and if you have any questions, feel free to contact us.

Medical clearance from a physician can be arranged here on Koh Tao upon your arrival. Once you arrive at Black Turtle, we can recommend local clinics and medical professionals who are familiar with dive medical assessments. Alternatively, you are also welcome to obtain medical approval from your local physician before travelling.

Structure of the PADI Open Water Course

The PADI Open Water Diver course is divided into three key components: knowledge development, confined water training, and open water dives. Each section is designed to progressively build your understanding, confidence, and practical diving ability in a safe and supportive environment.

The knowledge development portion of the course introduces the essential principles of scuba diving, including dive theory, equipment use, underwater communication, and important safety procedures. This foundational learning ensures students understand how to dive safely and comfortably before entering the water.

During the confined water sessions, students learn and practice the core scuba skills required for diving. These training sessions are typically conducted in a swimming pool or pool-like environment, allowing divers to develop confidence in shallow, controlled conditions before progressing further. Skills are repeated and refined at a comfortable pace until students feel relaxed and capable underwater.

To complete the course, students then participate in four open water dives at some of the dive sites surrounding Koh Tao. These dives provide the opportunity to apply everything learned throughout the course while experiencing real diving conditions and exploring the underwater world for the first time as a student diver.

Knowledge development

The theory portion of the PADI Open Water Diver course is divided into five sections, with each chapter building on the knowledge gained in the previous one. This step-by-step structure helps students develop a strong understanding of diver safety, equipment use, dive planning, and the marine environment.

Students receive access to the PADI Open Water manual through the eLearning platform as a digital e-book, allowing them to study at their own pace before and during the course. Each section includes a knowledge review made up of approximately 15–25 questions, which are typically completed during instructor-led sessions to reinforce understanding and clarify any areas of uncertainty.

At the end of each section, students complete a short 10-question quiz before progressing to the next chapter. Once all five sections have been finished, there is a 50-question final exam consisting of multiple-choice answers, with a required pass mark of 75%.

The final exam must be completed before students can receive their certification. However the exam can be completed at any stage and does not need to be finished before confined water training or the open water dives, giving students flexibility throughout their learning process.

Multi Choice Answers & Quizzes

This approach allows students time to fully absorb the information and apply it in practice, making the final exam far more manageable and helping them complete it with confidence.

Each theory section is also supported by a corresponding PADI training video, which can be viewed through the eLearning platform or during classroom sessions. These videos explain the concepts in greater detail, reinforce key safety principles, and provide a clear preview of what to expect during confined water training, including the core scuba skills you will be learning and practicing in the pool.

Confined Water Dives

Confined water training is an essential part of the PADI Open Water Diver course and can be conducted either in a swimming pool or in a body of water that offers pool-like conditions, such as a shallow, sheltered bay.

At our dive centre, we choose to carry out confined water sessions in a dedicated swimming pool, as this provides students with a calm, clear, and highly controlled environment in which to begin their training. Learning new scuba skills for the first time can feel overwhelming, so starting in comfortable conditions helps build confidence and allows students to focus fully on developing proper technique.

When confined water training is conducted in the sea, conditions such as waves, visibility, currents, and changing weather can all influence the learning experience. By using a pool, we are able to minimise these variables and create a more relaxed and effective training environment before students progress into open water.

During the course, students complete five confined water dives, beginning in shallow water where they can comfortably stand, allowing them to gradually develop confidence and familiarity with their equipment before moving into deeper training exercises.

Start in Shallow Water

Your confined water training begins with one of the most exciting moments for any new diver—taking your first breaths underwater. While breathing through a regulator and hearing the sound of your own bubbles may feel unusual at first, most students quickly adjust and often find the experience surprisingly calm and relaxing.

From there, your instructor will guide you through the essential foundation skills, including regulator recovery and clearing techniques, as well as mask clearing exercises to help you feel confident and comfortable underwater. You will also practise a stationary out-of-air skill, teaching you how to respond safely and calmly in an emergency situation.

Once these core skills are established, you will progress into deeper water for your first true underwater swim. Here, you will begin using standard scuba hand signals for communication, while also learning proper equalisation techniques to manage pressure changes as you descend.

Buoyancy Control & Skill Development

In the deeper end of the pool, the focus then shifts to buoyancy control—one of the most important skills in diving. You will practise hovering neutrally buoyant, maintaining good trim while swimming, and performing controlled descents and ascents without making contact with the bottom, helping you build strong habits for safe and environmentally responsible diving.

In addition to these core skills, students will also practise deep-water entries, complete a short underwater swim without a mask, and learn how to remove & replace your scuba equipment while submerged. These exercises are designed to build confidence, problem-solving ability, and comfort in situations that may feel unfamiliar at first.

Mini Dive Practice

To complete your confined water training, you will plan and carry out a mini dive using the PADI Dive Planning & Skill Practice Slate. This final exercise is a short, simulated version of a real open water dive and brings together everything you have learned throughout your pool sessions.

The mini dive includes preparing and assembling your equipment, performing your pre-dive buddy check, entering the water safely, completing a controlled descent, and swimming underwater while responding to simple skill challenges along the way. You will then finish with a safe and controlled ascent, giving you a full preview of what your open water dives will feel like and helping you transition confidently from the pool to the ocean.

The mini dive gives you your first real sense of what your open water dives will be like, allowing you to bring together everything you have learned throughout the day in one complete diving experience. It is often the moment when students realise just how much progress they have already made—from those first breaths underwater to confidently managing their equipment and moving comfortably beneath the surface.

By the end of the mini dive, you will begin to feel more like a diver rather than a beginner, and this confidence only continues to grow as you progress into your open water training in the ocean.

Open Water Dives – Explore the Ocean

We have saved the most exciting part for last—your four open water dives in the ocean, completed at some of the incredible dive sites surrounding Koh Tao. This is where your training truly comes to life, as you transition from the pool into real diving conditions and begin exploring the underwater world as a student diver.

Throughout the course, students typically visit three to four different dive sites around the island, giving you the opportunity to experience a variety of marine environments and reef systems. One of the advantages of learning to dive on Koh Tao is that travel time to dive sites are relatively short, allowing for more time in the water and less time spent commuting.

During each open water dive, you will repeat a selection of key skills to demonstrate comfort, control, and confidence in a natural environment. Most of these skills will already have been introduced and practised during your confined water training in the swimming pool, making the transition into the ocean feel smooth and familiar.

Maximum Depth 12 Metres on Dives 1 & 2

Your first two dives are where the foundations are built. While you’ll be practicing essential skills, you’ll also spend time refining your swimming technique, improving trim, and developing confident buoyancy control—all key elements of becoming a comfortable, capable diver. And it’s not all training—these dives still offer plenty of opportunities to enjoy Koh Tao’s vibrant marine life along the way.

Progressing onto Dives 3 & 4

By your final two dives, you’ll begin to step into more independent diving. You’ll practice controlled descents in open water without relying on a reference line, building both confidence and awareness. In most cases, all core skills are completed by the end of Dive 3, leaving your final dive free to do what it’s all about—relax, explore, and fully enjoy the underwater world.

Open Water Dive 4 is often considered the most rewarding part of the PADI Open Water Diver course, as it serves as your certification dive. During this final dive, you and your dive buddy will work together to plan and carry out the dive, applying everything you have learned throughout your training.

Although your instructor will remain with you throughout the dive, the focus is on demonstrating that you can dive safely and confidently as a competent recreational diver. This includes showing good buoyancy control, awareness of your dive limits, effective buddy communication, and the ability to conduct the dive responsibly within recreational depth and safety limits.

Because all required skills have usually been completed by this stage, Dive 4 is often referred to as the “fun dive.” With no formal skill practice remaining, you can simply relax, enjoy the experience, and fully appreciate the excitement of exploring the underwater world as a newly qualified diver.

Aquatic Life & Marine Diversity

One of the highlights of learning to dive in Koh Tao is the incredible variety of marine life you can encounter during your open water dives. The island’s reefs are full of vibrant coral ecosystems, giving new divers the chance to experience far more than just skill practice during their training.

While some time on each dive is dedicated to completing required scuba skills, this usually takes up less than half of the dive, leaving plenty of time to relax, explore, and enjoy the surrounding reef. It is this balance of training and exploration that makes the PADI Open Water course such an exciting experience.

Students can expect to see a wide range of colourful reef fish, including Butterflyfish, Angelfish, Bannerfish, Wrasse, and Parrot fish moving through the coral gardens. There is also a good chance of encountering larger and more memorable species such as Titan Triggerfish, as well as everyone’s favourite—clownfish, often affectionately referred to as “Nemo,” along with their smaller relative, the Pink Anemonefish.

Hidden among coral crevices and beneath rocky overhangs, you may also spot Stingrays resting on the sand or Moray Eels peeking out from their shelters. One of the most loved encounters for many divers is the Black-Spotted Porcupinefish, known for its large eyes and unmistakably expressive face.

At JJunkyard Reef dive site, one particularly famous resident is a Black-Spotted Porcupine affectionately known as Steve, who has become a favourite among both students and instructors. This site is also home to the bright and distinctive Yellow Boxfish, another species that never fails to impress new divers.

Special Encounters around Koh Tao

One of the most memorable experiences during your training in Koh Tao is the possibility of encountering larger marine life. Many of the island’s dive sites are home to both Green Turtle and Hawksbill Turtle, and seeing one of these graceful animals gliding effortlessly through the reef is often a highlight for new divers. Sharing the water with a sea turtle is a truly unforgettable experience and one that many students remember long after their course is complete.

On particularly lucky occasions, students may even encounter a Whaleshark during their Open Water training dives. As the largest fish in the ocean, whale sharks are an incredible sight and one of the most exciting marine encounters a diver can have. They are more commonly seen at the deeper dive sites around the island, although they do occasionally visit shallower reefs as well.

These deeper sites are often explored during continuing education courses such as the PADI Advanced Open Water, particularly during the Deep Adventure Dive, where divers have the opportunity to experience a wider range of dive environments and increase their chances of encountering some of Koh Tao’s most iconic marine life.

Get your PADI on Koh Tao

After your final dive and post-dive debriefing, it is time to celebrate—congratulations, you are now a certified PADI Open Water Diver. Your instructor will complete and submit your certification paperwork to PADI, who will then issue your certification directly to you.

Earning your Open Water certification is a significant milestone and marks the beginning of your diving journey rather than the end. For many new divers, completing the course only increases their excitement to continue learning, which is why the PADI Advanced Open Water course is often the natural next step.

Throughout your training, there is a strong focus on building excellent buoyancy control, confidence, and safe diving habits from the very beginning. By learning to dive to a high standard while enjoying the experience along the way, you leave the course not only with a certification, but with the skills and confidence to continue exploring the underwater world for years to come.

Highest Training Standards & Safety

Mastering buoyancy control is one of the most important skills you will learn as a diver. Not only does it help you become more confident and comfortable underwater, but it also allows you to dive responsibly by protecting the fragile marine environment around you. Throughout your Open Water dives, you will explore vibrant coral reefs filled with tropical fish, colourful hard and soft corals, and an incredible variety of marine life.

Earning your PADI Open Water certification is more than just learning a new skill — it is the start of an unforgettable adventure. The moment you take your first breath underwater, you will discover a whole new world beneath the surface, and chances are you will immediately want more. If you have been dreaming of learning to dive, now is the perfect time to take the plunge and join the Koh Tao PADI Open Water course.