Cave Diving: Important Things You Should Know

Cave diving combines the thrill of scuba diving with the wonder of spelunking for a truly unique experience. Cave and marine environments each hold some of the most unusual and diverse ecosystems on the planet. Underwater caves have very little light, food, or oxygen. Because of these unique conditions, they’re teeming with life that humanity doesn’t see often, and still doesn’t really understand.

Cave divers have discovered new kinds of bacteria that are helping us safely study antibacterial resistance. They’ve also discovered whole new animal species that had never before been seen by modern human eyes. They’ve discovered the remains of ancient, human-like creatures that have challenged everything we know about how humanity came to be. Cave divers are often on the forefront of discovery. While it’s easy to assume that in our modern world, every inch of the planet has been covered and catalogued, that simply isn’t true. And many of our most mysterious uncharted territories come in the form of caves, above water and below.

But even caves that have been explored fully are still worth seeing. Caves are full of unusual rock formations, other-worldly landscapes on all sides that are breathtaking to explore. And if the creatures and the scenery aren’t enough of a draw, there’s also the challenge that cave diving presents.

 

Common Cave Diving Hazards

For all of cave diving’s appeal, it’s also one of the more dangerous things that a scuba diver can do. Like ice diving and wreck diving, it’s a form of penetration diving, and is considered technical diving.

With no open surface above, divers must be extremely careful about navigation and oxygen management. If you plan on cave diving, you’ll likely need to use a dive light to help deal with low-light environments. You’ll also want a guide line for navigation, in case a silt-out destroys visibility. Expect to make decompression stops as you ascend, due to the amount of time cave divers spend at depth.

Of course, most of those hazards are typical of wreck diving, as well. But cave diving also presents its own, unique challenges. In caves, you may encounter thousands of feet of maze-like passageways that can be difficult to navigate. Nature doesn’t care about what makes sense to humans, so natural formations may not be as easy to figure out as the passages of a sunken ship.

Cave divers may also need to be mindful of falling rocks. And since many caves are part of springs or siphons, they may have currents stronger than what you might expect. Those currents may flow in or out of the cave, depending on the cave. This current will affect whether you exert yourself more to enter or exit, which will affect how you use your gas.

 

Safety Essentials for Cave Diving

While cave diving does present many hazards, proper training and precautions can strongly reduce those hazards. Cave diving isn’t foolhardy. But it’s important to know what you’re doing if you pursue it. Cave divers have a checklist of essentials to help reduce risk. They remember TGDAL: Training, Guide, Depth, Air, Light. Or, as some people remember this checklist with the phrase “The Good Divers Always Live.”

Training

Certification from an accredited organization is essential in order to begin cave diving. Most cave diving injuries or deaths are completely unnecessary, caused by people cave diving without training, or people going further into caves than their experience really allows.

Guide Lines

You should always have a guide line between the leader of the dive team, and a point outside the cave in open water. You may also tie the guide line down near the entrance of the cave, as a second point of safety.

Depth Rules

Cave diving often takes place at low depths, so be prepared to make decompression stops as you ascend. As you explore a cave, it may be easy to focus on navigation and lose track of how deep you are. Be mindful of your depth, and take care not to go lower than you planned to. If you accidentally do go beyond your planned depth, be ready to make up for it with a safe, slow ascent.

Air (Gas Management)

As with other penetration diving, it’s a good idea to follow the rule of thirds. Spend 1/3 of your air descending and exploring, and 1/3 of your air getting back, setting aside 1/3 for emergencies. If you slip up on the depth rules mentioned above, that extra 1/3 of your air can be very important for making stops to prevent decompression sickness. You may also need it to support someone on your dive team.

You might need to adjust the rule of thirds based on the flow of water in the cave. If the cave doesn’t have a strong outflow, or if the current is flowing into the cave, you may need to be more conservative than the rule of thirds suggests. You’ll need extra air to push out of the current and leave the cave.

Another thing to consider is your gas mix. It’s important to take an appropriate gas for the depth that you plan on reaching.

Dive Lights

The saying goes “Three lights is two lights; two lights is one light; one light is none.” When you’re diving in environments where light can’t reach you, Being able to see what you’re doing is essential. You don’t need all three lights to have the same intensity. One can be a primary light for exploration, with the other two as backups. But all three should have enough power to last you for the whole length of the dive. In underwater lighting where performance, reliability and simplicity are the keys to success, nothing beats the no-nonsense Nova 850 Tec. Divers looking for simple yet serious underwater illumination for night dives as well as day dives will find this dive light a smart choice.

 

Cavern vs Cave Diving: What Is the Difference?

Like wreck diving, there are several types of diving that are adjacent to cave diving, each one presenting more intensity, and requiring more gear and training.

Open water diving near caverns is the first step. This is where you have a visual on the cave, but can still swim straight up from where you are and break the surface. You’re near the cave, but not in it. Because some cave systems can have a strong inflow of water, this still presents some hazards, and is generally done as part of training.

Cavern diving is like limited-penetration wreck diving. You venture a little bit of the way into the cave. You have a cave ceiling overhead, and you’re lightly exploring the cavern. But you should always be able to see the entrance, and natural light. The National Speleological Society’s Cave Diving Section (NSS-CDS) defines cavern diving as no deeper than 70 feet, and within 130 linear feet of the cave entrance.

Cave diving pushes deeper into the cave than cavern diving. This is the point at which you move from recreational into technical diving. Certification, fitness, and top-notch, specialized scuba gear become real necessities at this point.

 

What Certification Do I Need to Be a Cave Diver?

There are a few cave diving courses that can help you on your journey. PADI does not offer a cave diving course, but Advanced Open Water Divers who are at least 18 years old can enroll in the Cavern Diver specialty course.

You’ll complete four scuba dives for the course. The first teaches you line handling, reel use, and emergency procedures outside of a cavern. The next three dives take place inside a cavern. They let you put your lessons from the first dive in practice. They also help you learn the equipment you need for cavern diving, like lights and redundant breathing systems. You’ll learn how to stay oriented and avoid silt-outs. You’ll also learn how to plan your dive, including depth and distance limits, and air management.

The NSS-CDS offers several classes for learning to cave dive, including basic Cave Diver and Advanced Cave Diver classes. They also have courses in Cave Surveying, Cartography, a First Responder course, and more. As one of the premiere authorities on cave diving, they can offer you the specialized skills you need to explore caves as much as you want to, as safely as possible.

You can also find cave diving classes at other organizations, such as the Intro to Cave Diver and Full Cave Diver classes

 

Diving Techniques to Use While in a Cave

As with many other penetration diving scenarios, cave diving requires some special techniques. It also demands careful use of techniques that many people may not think about much after they finish their certification. You’ll need particularly strong buoyancy control skills, unique methods of getting around, and even a special cave diving posture.

Buoyancy

Pay attention to your BCD. You’ll need good buoyancy control in order to safely cave dive. You’re navigating tight spaces, often with strong currents. You cannot be fighting to stay in position. You'll wear yourself out, and risk kicking up silt.

 

Movement Techniques

Silt-outs can be a problem when cave diving. They ruin visibility. This is one reason guide lines are so important. You may need to find your way back without being able to see what you’re doing.

This need to avoid disturbing the silt will affect which techniques you use to move around. Here are some common techniques used to propel cave divers without stirring up silt. Many of these techniques will be familiar to open water divers, but probably not used much. Their utility lies more in tight spaces. You’ll need to brush up on and/or learn:

• Frog kicks
• Flutter kicks
• Back kicks
• Helicopter turns
• Pull and glide (where you use the tips of your fingers to find crevices in the rock, and pull yourself along by hand)

Posture

Diver posture also matters. You can’t use regular scuba diving techniques. Cave divers must swim face down, with knees bent and fins elevated above the body. In addition to preventing silt, you may be able to propel yourself by pushing off of the cave ceiling, if it’s made of something sturdy, like limestone.

 

Best Equipment For Cave Diving

When you’re cave diving, you need scuba equipment that can withstand the rocky environments, low depths, and cold temperatures. And since it can be a long way to the surface, you want the absolute most reliable gear you can buy. Here are some recommendations.

Fins

Diving in an overhead environment often requires short, controlled flutter kicks, so that you don’t stir up silt. A stiff, high-performance fin works best. One stiff fin that’s great for maneuvering overhead environments is the Jet Fin.

Regulators

Regulators for cave diving need to be tough. You want a rugged piece of equipment that can withstand tough currents and harsh environments. The ability to maintain even air flow in a strong current helps, too, One strong combo is the MK19/G260 Carbon Regulator.

Dive Lights

We’ve already talked about how important dive lights are. When you’re cave diving, you’re in a truly light-free environment. It’s important to have lighting in triplicate, to be absolutely sure you can find your way. One strong light and two backups is fine, but they should all have enough power to last 1.5X the whole planned length of your dive.

Try the Nova 850 Tec light for cave diving.

Dive Masks

Masks are very personal, but here are some general tips for finding a scuba mask that works well for cave diving. You want:

• Low profile - a mask that doesn’t take up much space is important in a tight environment
• Black frame - to absorb stray light that may distract or interfere while your eyes are focused in a low-light environment
• Wide lenses - so that you can see the greatest possible area
• Well-fitted - for a comfortable dive

We recommend our frameless mask, or mini frameless mask if you have a smaller face. It allows you to have great peripheral vision for navigating small spaces.

Scuba Suits

Your scuba suit should be ready for the cold. You’re going to a place where no sunlight reaches, so there’s nothing to warm the water. You either want a thick wetsuit, or the extra protection of a drysuit. You can find warm wetsuits here in men’s and women’s styles. You can find drysuits here in men’s and women’s styles.

Guide Lines

We’ve already talked about the importance of having a guide line. Your line should be tied down outside of the cave, and possibly tied down again inside, close to the entrance. If a silt-out ruins visibility, or if all of your lights fail, your guide line is the only thing you’ll have to help you reach safety. But even during a smooth situation, it’s an important tool to help you quickly navigate to the exit.

Appropriate Gas Mixes

Make sure to use a gas mix that’s appropriate for the duration and depth of the dive. A cave is the last place that you want to find yourself loopy with nitrogen narcosis, so choose your gas well.

 

A Worthwhile Challenge

People talk a lot about safety when they talk about cave diving, because it’s important. Some of the conversation around cave diving has been led by people doing it wrong. Cave diving can be safe and fun, but it is absolutely imperative that you get certified and take all appropriate precautions before venturing into a cave.

That shouldn’t scare you away from pursuing cave diving with the appropriate training. Cave divers get to be explorers, seeking out new life in environments most eyes never see. Many serve as rescue divers, performing heroic rescues when people are trapped in caves.

The opportunities that cave diving provides are endless. Any diver willing to rise to the challenge can find themselves rewarded with otherworldly beauty and unparalleled opportunities to explore.