Cave diving is an extreme branch of scuba diving that opens doors to some of the most unexplored areas on earth. Below, we cover everything you’ll want to know before signing up for your first course.
Who should consider a cave diving certification?
Cave diving has a vast array of applications, both professional and recreational. If you’re a proficient recreational diver, thrill-seeker, and want to explore areas that few others get the chance to, cave diving is the perfect tool.
As a professional in various fields, you may also need to be cave certified to perform certain tasks. Here’s a quick list of just some of the professions that may involve cave diving:
- Geological/Environmental/Marine Scientist
- Search, Rescue, and Recovery
Whether you’re considering cave diving as a recreational hobby, or a step towards your professional goals, there are a few essential considerations to make.
First, consider your previous experience and exposure to scuba diving. Cave diving is a hazardous sport and is only for the already proficient open water diver. Undoubtedly, no one should ever attempt to cave dive without the proper technical diving qualifications or in unknown cave systems. Second, consider your preferences while diving. Do you like to dive in open water environments with high visibility? Do you enjoy diving at night or in bad visibility conditions? Would you prefer a relaxed dive, or would you rather rush through ultra-stong currents? Cave diving can be an adrenaline-filled endeavor, so be sure you’re up for the challenge.
How to Get a Cave Diving Certification
Many agencies offer courses for cavern and cave diving certification, and each has slight variations in their entry and completion requirements. TDI, or Technical Diving International, is one of the world’s largest technical diving certification agencies. While world-renowned agencies such as PADI and SSI offer some form of cavern and cave diving courses, technical diving agencies such as TDI are often a better option for learning to dive in overhead environments.
TDI offers the full range of courses to reach Full Cave Diver certification, in the following order:
- Open Water Diver
- Advanced Diver – (Recommended – Not Required)
- Intro to Cave
- Full Cave
While you can start your cavern course as an open water diver, we highly recommend that you complete your advanced certification first. Refining your skills and comfortability underwater creates a far more safe and enjoyable experience when diving in overhead conditions, with near-perfect buoyancy control being the most essential skill to have mastered. Night diving experience is also highly recommended, while competence in basic decompression theory and diving procedures are mandatory.
Cavern Diver Certification:
Different from cave diving in many ways. Cavern diving often occurs in a cave’s mouth or somewhere like the cenotes of Mexico’s Yucatan Peninsula. While overhead obstacles may be present, natural ambient light illuminates the area from spaces that divers can surface.
Caverns must have a maximum depth of 70 feet and must have an entrance that exceeds 130 feet in linear width. The equipment and techniques used by cave divers are also different from cavern divers, explained further in the sections below.
You must satisfy the following before you can begin your Cavern course:
- Age of 18+, or 15+ with Parental Consent
- Open Water Certification or Equivalent
- Proof of 25+ Logged Dives
Keep in mind; these are the absolute bare minimum requirements to start your cavern course. In truth, the more experienced you are, the better.
During this course, you’ll learn about the necessary planning, procedures, techniques, equipment, and hazards of diving in an overhead environment. The skills learned during your cavern certification will be completed within light penetration limits, as cavern diving does not include full penetration into lightless settings.
Length: 3-5 Days
Experience: 4-6 Cavern Dives
Intro to Cave Certification:
This course’s primary focus will be to develop proper cave diving techniques, extended directly from your Cavern Diving course. Using a single guideline, you will learn how to navigate cave systems and manage problem-solving techniques. (Reference the “Training and Techniques” section below for details). For the first time, you’ll find out what it’s like to navigate in complete darkness by turning off your dive torch in a flooded cave. All of the skills you’ve been practicing will come to life in this environment.
Length: 3-5 Days
Experience: 5-7 Penetration Dives
Full Cave Certification:
This course is the third stage of overhead environment training and the last before Full Cave certification. In this course, you will learn advanced cave dive planning for various cave systems, how to execute the various scenarios that cave divers can face, and experience unsimulated lightless environments for the first time. Evaluation of divers will encompass the full spectrum of cavern and cave skills, including improvised cave diving techniques and blind skill scenarios.
Length: 4-6 Days
Experience: 8-10 Full Penetration Dives
Is Cave Diving Dangerous?
Full cave diving involves lightless, claustrophobic, and often cold environments, creating the real potential for distress and panic in even the most experienced open water divers. The number one cause of severe injury or death in full cave diving is not equipment failure, getting lost, or becoming trapped — the real threat is panic.
Cave diving with a history of anxiety or claustrophobia puts both you and your dive team at risk. With that said, specialized training, equipment, and techniques will support a confident and level-headed dive team through a truly unique and unforgettable experience.
Be sure to consider the location you’ll be cave diving and with who you plan to train. If you are diving from a boat, chances are you’ll be diving in ocean cave systems. As a recreational diver, you will likely have some exposure to ocean environments. Many caves, however, are located inland as part of freshwater systems.
There are a few significant differences between the two: buoyancy and temperature. Freshwater will prove far less buoyant than salt water, and even the most experienced ocean divers will need to re-perfect their buoyancy skills for freshwater systems. Water temperatures are almost always colder in freshwater systems, and even colder in deep, lightless cave environments. Cooler water temperatures affect divers in a multitude of ways, so it’s beneficial to have some previous experience in these conditions to see how your body reacts.
Keep in mind – not all cave diving instructors should be treated equally. Many instructors have expertise in a specific location or conditions, so consider their experience when choosing a course director to train with. It’s critical that the training you receive mimics the conditions and environments you plan to dive.
Cavern and Cave Diving Equipment
In comparison to recreational diving, there are significant differences in the equipment used for cave diving. As you move through your courses from Cavern to Full Cave, you will learn to use different gear and tools.
Cavern Diving Equipment
When you begin your cavern course, you’ll start to see changes from your recreational dive gear setup.
Dangling air gauges, inflator hoses, and secondary air sources are tightened up and consolidated. Snorkels are removed, dangling fin straps are taped down, and any dive accessories are fastened securely. Repositioning your weights to make yourself slightly top-heavy lifts your fins away from the bottom, preventing silt and sediment from being stirred up. Specialized short fins help avoid kicking divers behind you and allow for special finning techniques required for cavern and cave diving, and steel tanks help mitigate buoyancy changes that occur with standard aluminum tanks as air depletes.
Cavern divers will also need the following additional equipment:
- Line and Reel
- Dive Torch and Backup
- Dive Knife
- Underwater Slate
Cave Diving Equipment
When you move into your cave diving courses, more significant changes in equipment are present.
First, a two-tank system ensures that you have the air supply required to backtrack out of a cave system. There are two ways to carry a two-tank setup, and each will require a bit of additional training. The first and most popular is the traditional back-mount. This setup is more than acceptable for most cave dives and is easier to learn than the alternative. With tanks positioned on your back, buoyancy changes will have less of an effect on the diver than a side-mount setup.
The side-mount setup positions one tank under each arm along your body. Each tank is a separate air source, and each has its own regulator, which you will need to switch periodically to keep evenly distributed buoyancy as air depletes. Side-mount diving allows for greater versatility in a smaller cave system, as it’s easier to maneuver and squeeze through tight spaces.
As you fully penetrate a cave system, a helmet protects your head and often includes an attached dive light. Because you’re penetrating deeper into cave systems, multiple line-and-reels are required. In addition to the two dive torches used in cavern diving, cave diving requires a third backup.
Cavern and Cave Diving: Training and Techniques
Again, cave diving requires specialized training and techniques that are often not learned by recreational divers. Mastering these will be vital to ensure the safety of you and your team.
The primary “flutter kick” that every diver learns in their open water course just isn’t applicable for cave diving. Instead, there are a variety of finning techniques used for certain situations inside of cave systems. Here are the most common and useful:
Modified Frog Kick: This is the primary finning technique used in cave systems. The modified frog kick begins with your fins outward and upward at a 90-degree angle, with your fin blades parallel to the bottom. Step two brings your legs straight while pushing your fins in an arcing motion and bringing the soles of the fins together. The frog kick is the most efficient kick a diver can use, and it keeps your fins in an upright position, preventing silt and sediment from being kicked up.
Helicopter Turn: The helicopter turn is a technique used to turn around or in one direction in a small space. Start in the same position as the frog kick, keep on leg stationary, and move the other leg in a frog kick motion. This motion lets you pivot in place as if turning on your belly button.
Modified Flutter Kick: The modified flutter kick helps to fight flow when entering a high-flow cave system. With your legs in a frog kick position, you kick straight back without dropping your knees below your shoulders or stomach. The bicycle motion your legs make helps fight against the flow without moving up or down in the water column.
Line and Reel Training
Perhaps the most crucial aspect learned in cave diving is the use of a line and reel. The line and reel is, without a doubt, your literal lifeline in a cave system – and knowing how to use it properly can be the difference between life and death.
Before you penetrate a cave on your first training dive, you’ll practice line and reel techniques on land such as:
- Laying a line
- Following a line blind
- Finding a lost line
- Fixing a tangled line
- Laying a gap line and jump line
- Repairing a broken line
A “gap line” is a new line beginning near the end of an existing primary line, which extends to explore further into the cave.
A “jump line” is a new line used to change direction somewhere along an existing primary line. Jump lines reduce the risk of losing your primary line when exploring new and separate passages within a cave system.
It’s best to install gap or jump lines as close to the primary line as possible.
During a dive:
First, a primary line ties off with a “primary tie” in an open water area – generally at the mouth of the cave. The primary line should always lead you to open water where you can reach the surface. Once descending into the “cavern zone,” a “secondary” tie-off is made. If something happens to the primary line, this will lead you to the mouth of the cave, where light is visible, and the surface is identifiable.
After penetration, a safety tie-off is made every time direction changes. By staying linear and directional, finding the line in an emergency becomes easier. Ideally, line placement should always be near the cave’s floor, allowing divers to swim above it and avoid entanglement. Line placement must be in an area where all divers can maintain physical contact, especially in zero visibility situations resulting from silt and sediment disturbances.
Once you’re cavern and cave certified, it may be time to set yourself up to dive from your boat. Just be sure that you follow your training carefully when not diving with an experienced local guide, and never dive alone.
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