Here are a few items you can include in your logbook to help you stay organized and honest, track progress, and work on self-improvement as a diver.
I’ve had the good fortune to be in the company of some of the most respected overhead divers/instructors/instructor trainers spanning the globe.
Cave divers use a distinct set of markers to determine direction and distance traveled in a cave.
Don’t get lost cave divng. Read one man’s story about how he almost ran out of air cave diving.
The only plan we had when TDI Instructor Trainer Ben Reymenants asked us to join a trip to Chiao Lan lake’s floating rafthouses was to do nothing at all; read a book and relax for a couple of days on the water. The group we went with was packed with cave divers and students ready to explore the secrets that hide inside the local caves. Our initial plan was to tag along and make one or two dives to peek into the dark abyss in front of the cave. Well, it didn’t turn out as planned. Curiosity got the better of us and we decided to enroll in the cave diving course. I’m fairly certain Ben knew that all along because he had equipment ready for us to use.
Dark as a night; one only sees the wide light beam emitted by the torch held by your small shaky hand. There is a good chance that you may not see your own light if the diver in front of you decides to stir up some sediment. That’s why you have to obey the one golden rule – no matter what happens or what you are doing, never ever lose your guide line. It just so happened that somebody (not pointing fingers) gently removed our masks and as you might know, seeing underwater without a mask is a bit complicated. Here we go, now it’s time to start exiting!
You must be certain the direction you’re going is the right way out. If you lose the line, you’re in trouble. By holding the line and feeling the previously placed directional markers on it, we started slowly moving towards the exit. Usually when something goes wrong other things that were good until this point start to go wrong as well. It becomes a downward spiral. For example, you may run out of air in addition to zero visibility. That’s another reason to have a good teammate in there which is why I think cave diving is more teamwork than a marriage.
It’s not an ego thing that demands a cave diver to be in good shape. You need to be able to swim long distances without getting tired. Inside a cave, you no longer have the option to go up when you would like to end the dive. As far as you swim in, you must be able to swim out.
There are thousands of years of history recorded in the caves. The caves in Chiao Lan are formed by acids found in the ground and rainwater that dissolved limestone and made cracks in it. It takes thousands of years more until cave systems are formed until, for some natural or artificial reason, the caves are flooded and become home to a very unique ecosystem.
There are stalactites hanging down from the ceilings revealing time stamps and stalagmites grow from the floor like trees. There is almost no vegetation and fauna is quite scarce. You can find some near blind cavefish that may bounce off you during the dive because of they don’t see you (obviously), along with white crabs and lobsters, mustached catfish and snakehead fish dating back to ancient times.
During the last couple of years, it seems I constantly have to test my limits. Like now – I didn’t know anything about cave diving but Ben Reymenants and Paul Kirby taught us the skills necessary to navigate in the caves, deal with entanglements, find the exit in zero visibility, and much more. Over the time I’ve developed some sort of peace and mindset that I’ll do the things as well as I can. A cave diver has to know how to lay a line and tie knots because the line that leads you into the cave is like an umbilical cord; it’s your lifeline that supports you. I practiced my lifeline skills a lot during that week, invented some totally new knots and mastered the known ones.
Tuuli Piirsalu is working as organization development manager for Daimler Financial Services in Singapore. Before urban life she worked as a diving instructor in Egypt, Maldives and Thailand.
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“More than 300 divers – including open water instructors — have died in caves just like this one. Prevent your death. Go no further.”
Now, I can’t speak for anyone but myself, but when I was a fledgling open water diver, if faced with a sign that shared that little snippet of information with me, I am pretty sure that I would have turned around and gotten the heck out of dodge. Big signs with that wording and an image of the Grim Reaper are placed at the entrance to most caves in Florida as well as other spots in the Bahamas, Mexico and so on. But sadly, many divers, divers who have no business being in any overhead environment and especially a cave, choose to ignore them.
The question is why?
If you take a look through the standards for SDI’s open-water programs – from beginner to open-water instructor trainer – there are some very specific recommendations to stay away from “overhead environments.” For the record, an overhead environment is ANY spot from which a direct ascent to the surface is not possible. And to further clarify, a direct ascent means that if a diver were to fill a lift bag, DSMB, or balloon at depth and release it, it should make it to the surface without touching rock, wreck, coral or anything else. If that lift bag, DSMB, or balloon DOES touch anything at all, the diver should be trained and equipped, to be there.
OK, more definitions. It’s fair to say that the foundation of most of the skills, techniques and gear associated with technical diving have their beginnings in cave diving. Cave diving is – to many – where sport diving stops and technical diving begins. Certainly, courses in cave diving from TDI are considered “Fully technical” and for good reason.
Since the inception of structured cave diving education, the progress from being an experienced open-water diver to a full cave diver has followed a similar pathway regardless of the certifying agency or location of the program being offered.
It begins with a cavern course. This program is designed to introduce basic skills such as how to swim without kicking up a huge cloud of silt; how to use a reel and deploy a line in water without getting tied up like a Christmas present; how to communicate with your buddy so there’s no ambiguity; and how to manage gas volume so that you and your mate have something to breathe for the duration of the dive even if something goes totally pear-shaped and one of you loses all his gas.
The next step in cave diver training is an Intro-to-Cave class. This builds on the fundamental skills presented in the cavern class and introduces more intensive equipment management drills. Graduates from this level of training can venture into the cave, but still have to function within certain limits, such as staying in the main passageways and making no jumps to side passages.
And finally is a full-cave class which essentially gives a diver a “licence to learn,” inside the cave proper and its off-shoots and side tunnels. But even then, there are limits and several other steps in both experience and training before this diver has “free-run” of the cave.
NONE of the skills required to help keep a diver safe in a cave or cavern are taught in a recreational open-water class… including an instructor class… and the equipment used by sport divers the world over has no place in a cave.
Caves can be beautiful but that beauty can become extremely ugly in a couple of heartbeats. Here are some things that have happened to untrained divers who almost died in a cavern or cave but somehow managed to find their way out.
“We only intended to swim in a little way, but there were lots of passages and we got turned around…”
“The water was really clear but my buddy crashed into the bottom and I lost sight of him and the exit. I think he is still in there…”
“We had a light between us but it went out. It was really dark and I kept swimming into the walls…
“I swum in a little way and then my octo started to freeflow…”
“We followed a line and it just stopped and then I got tangled in it…”
“I panicked when I turned and could not see the exit.”
Let’s look again at some definitions. The definition of a cavern, and the limit of a cavern dive, is that the primary light is sunlight. Cavern divers must still use and carry lights (several of them), but at all times, both divers must be able to see the exit of the cavern. And for the record, the Grim Reaper sign mentioned in the first paragraph is usually placed at the edge of the so-called cavern-zone… the transition point from cavern to cave.
Now, just in case you are thinking to yourself right now: “Well, I guess it’s OK to go and take a peek inside a cavern because the sign telling me to go no further is there and NOT at the entrance to the cavern itself” let’s consider a couple of things including the benefits and reasons behind the skills taught cavern divers.
Remember the first rule of scuba diving: Never hold your breath? Well, the first rule of technical diving delivers more or less the same message: “Always have something to breathe!” That way, you never HAVE to hold your breath and break the first rule of scuba diving.” That makes sense doesn’t it?
Many of the several hundred divers who have perished in caves have actually died in the cavern zone: right there within sight of the exit. How, you might ask, could that happen? After all, it’s just a cavern, nothing challenging about that! Well, as surprising as it may seem, they ran out of something to breathe because they could not see daylight. They had flutter-kicked their way a few metres into the cavern and in doing so had totally silted things out so badly that they were suddenly in a black-out. They found themselves lost! Then, with their breathing rate elevated because of stress… and then panic… they had used up their air supply in minutes while searching for the way out. In their confusion, some had actually swum further into the cave.
Occasionally, the poor sap who ends up dead may have been told that caverns and caves are safe, and believed it. There may even have been an open-water instructor telling them that it’s OK to follow them into a cavern or cave. Well, the truth is that is in NOT OK and dive leaders who take untrained divers into an overhead are breaking standards… pure and simple.
There are no grey areas when it comes to this overhead stuff. Going in there without the right kit and training is seriously tempting fate, and there are so many other ways to enjoy yourself with scuba. Please, please, do not go into an overhead until you get training in overhead diving and get yourself some serious kit and gain the experience to use it properly.
TDI instructor trainer #6
Contact SDI TDI and ERDI
If you would like more information, please contact our World Headquarters or your Regional Office.
Isn’t it time you learned more?
Perhaps one of the most common questions Technical Diving International’s (TDI) Training Department gets is “why do I need training for overhead environments?” While this question seems pretty obvious to TDI, we understand why it is not so obvious to the average diver. After all, you are breathing underwater, controlling your buoyancy and managing air just like you would on any other dive, right? Wrong. In this article we are going to focus on one specific type of overhead diving: caves.
Caves are one of the most fascinating environments a person can explore. Just think about it: these massive natural tunnels (some only a metre or 3 feet down) are below us, some dry some wet, while life on the surface moves along at its normal pace completely unaware that they even exist. These natural tunnels are responsible for a large portion of our drinking water and for moving water to the oceans or lakes to avoid flooding during rainy seasons and snow melt. Nearly every continent and country contains caves, most undocumented and unexplored. Some of these caves are just barely big enough for an adult to fit though while others are big enough to fit a descent sized town in.
While caves are undoubtedly fascinating, and there is clearly a need for them to be explored, they deserve a lot of respect and require specialized training before they are entered. Not all caves are made alike; some caves are low visibility with high water flow while others have clear warm water. Some caves are solid with no chance of the “roof” collapsing while others have what are called “breakdown rooms.” These rooms are where the earth above has been eroded to a point where it falls to the floor of the cave forming a large cone in the center; when this roof will fall is anyone’s guess. In some areas, even the caves that appear to be very stable are subject to seismic activity and could collapse.
The point here is that before entering any cave system proper training is required. Your TDI instructor, among other knowledge and skills, will teach you how the cave was formed and its stability. You will also learn things to look out for when planning a cave dive like “where do I look to find recent seismic activity so I know when it is safe to dive?”
Cave training is also a progression in training starting with caverns where you learn the basic techniques for deploying guidelines, buddy communication with lights and air management, all while staying in the ambient light zone. The next course is cave which takes you beyond the ambient light zone further into the cave requiring more air management skills and guideline techniques. The pinnacle of cave training is full cave; here you will learn complex circuits with jumps off the mainline and even more air management to allow for decompression dives. Please note: Decompression procedures is a pre-requisite for this course, decompression diving is not taught as part of the full cave course.
At any stage of your cave training you can add in other training such as: cave- diver propulsion vehicle (DPV), cave survey, sidemount or sump diving. There is a lot to do, see and learn just below the surface of the rock we walk on every day, but it requires some training from a TDI Professional. After this training you will be amazed at the exploration you will be capable of, and your friends will love the stories of your adventures.
So if cave diving is something you would like to learn more about, ask your local TDI facility or Instructor for more information. Our website is always a great place to start for additional information https://www.tdisdi.com, or simply give us a call at 888.778.9073 or 207.729.4201.