CCR Cave Diving
Cave diving is the art to dive into the overhead environment, into waterfilled caves, to glide weightless through large rooms or small passages, marveling at natures beauty. There are a number of rules and techniques that need to be followed and implemented in order to succesfully cave dive, meaning coming out of the cave having a good time instead a stressfull experience. CCR Cave diving is the art of cave diving combined with the art of CCR diving.
In order to learn cave diving propperly a training program has to be completed either in stages or in whole, with considerable amount of time to be invested learning and repeating new diving skills and procedures. Your commitment and resolve will be tested here through intense training days filled with awesome diving experiences.
CCR and cave diving do have serious consequences if one is to violate the rules and procedures for one or another, or both. Failure to do so might prove fatal. The CCR Cave Diver course is one of the most intense training programs there is, with large potential for frustration.
If you wish to learn cave diving using your CCR you must have operation as well as the buoyancy control of your unit down as to second nature in order to concentrate to the learning on how to cave dive. Training agency standards require you to have a minimum of 30 hours on your Rebreather before participating in a CCR Cave Diver course.
We mainly teach CCR cave diving on the Megalodon, Optima, Evolution, Inspiration, Sport KISS and Classic KISS CCR Rebreathers besides other units.
Are you ready for cave diving
Ready for cave diving includes, but is not limited to the following considerations that set it apart from open water diving activities. No amount of open water diving experience is preparing a diver for the overhead environment.
Experience
The trained and experienced open water CCR diver interested in Cave Diver training should consider that diving in the overhead environment requires more equipment with the ability to handle that equipment even in stressful situations. In general it is recommended to have between 50 – 100 successful dives concluded with a variety of diving situations such as navigation, night diving, and deep diving before entering and enrolling into a cave diver course, as well as a minimum of 30 hours on the CCR the CCR Cave Diver course is taken on.
In order to dive in water filled caves the need to carry a larger amount of breathing gas for penetration and bailout. The bailout tanks are carried by a special harness in a stage or sidemount configuration, buoyancy is provided by wing style buoyancy compensator with sufficient lift. Lights and extra lights, reel’s and exposure suit not to forget. This can add to fatigue and stress and previous diving experience will help to focus on the new skills and environment ahead.
This equipment must be handled as well as the task loading activities encountered in cave diving. A certain amount of diving experience is paramount for a successful cave diving course.
Buoyancy
Buoyancy is one of the most crucial skills in cave diving. It provides the diver with a stable position to run lines, do tie off's, work with reel’s and pass easy through the cave and water column.
Neutral buoyancy in a horizontal position with the legs up provides the Cave Diver with a streamlined and balanced profile while that particular position does protect the cave environment. What looks to us solid may be fragile speleothems or soft silt that can be agitated or broken with one uncontrolled touch of the hand or fin. Divers must be able to turn in a horizontal position, maintaining the horizontal position and depth without touching anything. While this requires practice it requires dedication for cave preservation as well.
Mental considerations
The overhead environment is depriving us of one factor open water divers are used to in emergency situations, that is the direct access to the surface in case of emergency is possible and a depth reference to the surface can be judged. Water filled Caves are dark, full of water, might have a restricted passage and definitely have a rock ceiling. Cave divers can survive in this harsh and potential hazardous environment while carrying lights, Rebreathers and bailout tanks with breathing gas, stay in large passage and exercise the rule of thirds to get safely in and out of the Cave.
Fact is that in case of an emergency we must exit the Cave with that emergency all the way back we came in before we can get back to the surface and breathe ambient air. It is important that we do understand our equipment, get the proper training, use the proper techniques and procedures in order to dive the overhead environment safely.
A mental conditioning is vital for survival with a positive attitude for survival, with an understanding of the inherent risk associated with Cave diving, the willingness to strife for perfection in the art of Cave diving, the willingness to practice emergency exercises again and again until they become second nature. Cave diving is not for everyone but for experienced divers willing to make an effort and these divers will be rewarded with some of the best diving on this planet, and a truly unique experience.
Commitment
The commitment needed for Cave diving goes beyond the time spend in the water but does include serious challenges to one self physically and mentally. The rewards are great and satisfying. Enrolling in a Cave diving course is a step into a new world.
Long term commitments do not only include the investment for the proper training needed to dive the overhead environment safely. The financial commitment includes the equipment needed for this type of diving, the necessary life support equipment and the Cave diving to come, to continue and practice what was learned during the training program, not to get rusty but to practice and practice again.
Equipment
In today’s world a variety of Rebreathers are available for the avid Cave Diver. Rebreathers are usually used to extend gas volume in remote locations or deep Cave diving applications where the needed gas volumes are not feasible to carry. Personal preferences and logistics dictate the choice of a particular unit. Before Cave diving the diver has to be trained and experienced on open water rebreather diving and then can combine Cave and rebreather technique and technology with an experienced Instructor.
Penetration
Rebreathers have to be used with bail out systems assuring the diver a safe exit to the surface in case of a total loop and rebreather failure. The bail out can be carried or staged in gas depots within the Cave in the form of open circuit tanks or worn. Another way to carry a bail out system is in the form of another Rebreather carried by the diver. Rebreather diving has a potential high impact on the Cave environment onto the Cave due to different buoyancy characteristics. Care should be taken not to harm the Cave. Special training is needed to use a rebreather safely in the Cave environment, even if preveously trained in open circuit Cave diving.
Bailout
Bailout is the alternate path to the surface if our rebreather does not work anymore, for any given reason such as flood, not trusting it anymore or electronics failure. The CCR Cave Diver has a variety of scenarios and approaches that will get him back to the surface safely. The minimum gas that needs to be carried by the team is the volume needed to get 1 ½ divers back to the surface. Open circuit, a SCR or CCR can be used as bailout to bring us back to the surface in case of unit malfunction.
Team approach may work in most cases but it does not factor in team separation. I believe that having and major rebreather problem and due to that major problem in the cave environment we may create bad or zero visibility, that could be resulting in a team separation is not something I personally would like to leave out of the equation.
As the individual approach is allowing to have each diver sufficient gas to bring himself to the surface, plus a margin of reserve the student and later CCR Cave Diver has a larger gas reserve. During post training dives this can be practiced and then expanded upon to further penetration and team bailout approach.
The whole bailout concept needs to be understood by the student in terms of not having all the time in the world anymore when on open circuit bailout, as well having to do potentially some 25 - 30 % more decompression due to falling Po2´s on the way up, depending on dive profile. Teaching a CCR Cave Course without proper bailout planning capability to the student is nothing else then giving the kid a loaded gun.
A long 5 or 7 foot / 1.5 or 2 meter hose on bailout tanks is a must and the deployment of the long hose from the always open bailout tank must be well practiced during safety drills. That will be a life saver and in some environments the only way to deal with a failed CCR in the cave. Handing over the stage in a fluid motion while sharing gas now on o/c and being under time and mental pressure will only lead to further problems, delays and stress. The hand over and sharing of the 7 foot hose, and not the hand over of a stage tank will be the key to some real emergencies. However, the hand over and exchange of bailout tanks in-between divers must be well rehearsed to enable proper execution in case the skill is needed in earnest.
The balancing of bailout gas volume within the team, within all present bailout tanks must be followed in either 1) team approach because the needed volume is split up in-between the team members and the out of CCR diver need their gas to make it back to the surface or the 2) individual approach to not breathe the bailout tank totally empty and loose all redundancy when still with other team members. Larger gas supplies are present with the individual approach, even when diving as a team allowing for delays exits such as restrictions, zero visibility, potential team separation and increased RMV.
When talking about furthest point of penetration o/c bailout versus right before deco bailout it is the furthest penetration that would be most problematic, as the divers still have to do the exit out of the overhead environment and then do the decompression. As we are fortunate enough to talk about cave diving and not ocean drift diving we are able to stage the deco gas at the cave entrance, but having sufficient bailout gas traveling horizontally through the cave will be the trick. Potential air hogs who go CCR to have more time in the cave still need to sling them large bailout tanks or they going to be running out of bailout gas. Taking a bailout tank without proper volume planning is like Russian roulette, and must not be done.
Besides opting for o/c bailout a different options is present as Jochen Hasenmaier, Olivier Isler and the Wakulla II team went to CCR bailout for at least two reasons. First gas volume and the ability to carry it, drag and the like, second is time pressure of diminishing gas supplies and associated stress levels translating in errors and elevated RMV.
The bailout planning will bring with it the change of breathing gas and Po2, and along with it changing decompression times and gases needed to finish the warranted decompression. We need to take submersible bailout tables with us underwater in order to recalculate potential changes in dive plans as long we stay on our CCR. Submersible tables need to be designed for the breathing gases used during proper function of our CCR as well as the o/c bailout gases we may use. Planning dives with deco planning software including the calculation bailout scenarios and to deep and long profiles, and having them on a slate would be ok when diving known caves and profiles.
The other bailout way in terms of breathing gases would be o/c - c/c dive computers either wired into the loop with a separate sensor, or not, that can and must be changed when going from c/c to o/c in a bailout scenario. Diving with only one of such computers has no redundancy. Bailout gas volume calculations are a must and done separate to insure sufficient breathing gas volumes.
-Bailout Valve or BOV
It has happened that a diver managed to get in the water without Co2 absorbent in his unit, despite checklist and all that. As they went down at about 20 feet / 6 meters the diver was breathing uncontrolled due to exertion and higher PCo2. The dive partner realized what is going on and urged the student to switch to o/c. The unit was not equipped with a BOV. The diver was not able to make the switch as he was not able to hold his breath for even a split second to do the switch over. They went to the surface and they lived to tell the story.
With a BOV the diver would have been able to switch from his CCR to his o/c bail out without a problem. Additionally the other diver could have intervened and help the affected diver.
I believe that if I decide to go off my CCR then I am off and want to go to something that is not connected at all to my CCR. Most BOV are connected to the inboard dilluent tank. With the limited volume offered by the onboard diluent tank the BOV is just a step in-between, to get off the loop and then onto the seperate bailout tank. Take a breath or three then go on to your o/c bailout stage, which is a completely separate life support system with precalculated po2 and gas volume, and you know it’s going to work.
I have seen some divers who had there BOV plumed via disconnect into their o/c bailout stage tank and this way going onto your BOV you will not need to take the BOV out of your mouth to go onto your off board bailout tank, keeping your mouthpiece in your mouth to do a easy switch over and yet go off your CCR onto a separate tank at once.
When doing that last switch over to your complete detached and separate gas supply, you as well have decided you are not going back onto the CCR as you have decided you do not trust it anymore, other then providing buoyancy. And you stick with it. And while you at it change your set point to a low one and open the over pressurization valve from your counter lungs as you will go up. The BOV could be a life saver if used properly.
Something else I have witnessed with BOV equipped divers is that they tend not think about what gas they have in their BOV supply tank and use the BOV freely on the surface, and why not. It is that I just always imagine as they go on with their diving career and coming to trimix diving that this habit will have them killed on the surface, due to hypoxia breathing a low o2 content mix on the surface and exerting. As one habit might be good in one diving situation it may kill you in another.
Deep diving with higher pata and with it higher pco2's and a faster need to switch over might warrant the use of a BOV with the added ability of your team mates to help and intervene if you are possibly incapacitated already hy hyper- or hypoxia or hypercapnia..
What I have witnessed over and over again is that divers do hesitate to long, way toooo loooong before they decide to go to bailout ( either o/c SCR or CCR ) when they think something is not right. They start thinking about it, are not sure, they feel something is or was not right, don't want to be embarrassed or think the process of bailing out without a BOV is just to cumbersome and time consuming. The installation and use of a BOV can be a live saver.
If you just think about going off loop and to bailout but can not even put your finger on what or why, that very thought of just thinking about bailout is the very reason to bail out, now. Do not hesitate a split second and go to o/c bailout, because that might have been your last chance to do so.
The installation and use of a BOV can be a live saver. I am diving currently with a BOV (Golem Gear with CCR Megalodon and factory BOV with Classic KISS) and the only exception is my CCR O2ptima who does not have one.
If you have any questions please do not hesitate to e-mail me