When planning to take a CCR (closed circuit rebreather) cave diver training program, when planning to take a CCR into the cave environment a number of diver, training, drill and skill performance needs to be considered. The CCR cave diver training program is one of the hardest and most complex training programs there is.
We have to be able to do all CCR related emergency drills and skills in the cave such as hypercapnia, hyperoxia, hypoxia, partially flooded loop, complete flooded loop recovery, boom scenario and electronics failure in the cave environment while doing o/c bailouts over larger distances, running the rebreather manually simulating failed open or closed solenoids in a horizontal position not losing sight of the line, not bumping into the ceiling and not bumping into the floor causing a silt out and creating potentially zero visibility, increasing the stress factor and the potential need of embarking on a lost line scenario. You get the idea what I mean with complex activity.
As we plan to dive our rebreather in the cave we need to learn all about the cave diving skills such as diving horizontal, good buoyancy, anti silt propulsion techniques, good line laying technique in terms of getting from the openwater to the beginning of the permanent cave guideline and doing jumps or multiple jumps in complex navigation dives as well as the cave diving related survival drills such as primary light failure and backup light exit, sharing gas with a buddy providing o/c bailout gas from our bailout tank, handing over bailout tanks, touch contact in zero visibility, lost line scenarios is zero visibility, searching for a lost dive partner potentially in zero visibility just to name a few. On top of that we need to dive our rebreather.
In order to be able to learn, conduct and participate actively in the above CCR cave training scenarios the CCR diver needs to have good buoyancy and trim skills as well as having a thorough understanding of his or her particular rebreather model to be able to still manipulate and control the CCR in adverse conditions when stress might be high and visibility low. Over time skills get rusty and get lost. It is important to rehearse and hone these skills in order to be ready to receive the ccr cave diver training. If you are not ready but rusty you will be in for a very frustrating experience.
An important step to prepare for a planned and upcoming CCR cave diver training program is to work hard on buoyancy and trim skills. It is a fact that a cave diver has to dive horizontally and it is a fact that a cave diver has to stay away from the silt on the floor and the ceiling, besides not to damage the fragile cave environment. What’s the use if we like to cave dive but fuck up the cave in the process.
During a pre training program period buoyancy and trim should be especially worked on and practiced. Best to do it in very shallow water, a pool or confined water area with a max depth of 20 – 30 feet / 6 – 9 meters. I know it’s not easy but this is the point exactly. The skills to work on are the skills you need in order to dive in the cave environment safely, and all skill should be performed in a horizontally position not touching the floor or ground and neither the water surface as these both signify the cave floor and ceiling. All drills should be practiced in a way that you do not swim in circles but can do them stationary. All drills should be practiced in full cave diving gear including the bailout tank or tanks, lights, hood, primary light, backup lights, reels. The whole nine yards.
First get your diver skills up. Practice buoyancy, horizontal trim and proper weighting. Most cave environments are in fresh water so check out the weight you carry. Practice propulsion techniques out of the cave diver leg up position such as modified flutter, frog, shuffle and reverse kick. The reverse kick is super important as it lets you stop and back up without the use of your hand which could stir up sediments. Once you have these skills down practice CCR related skills. Being able to turn on a dime with the helicopter turn will prevent you from going in circles and loose direction and orientation.
Once you have your diver level skills sorted and you are able to stop, backup, do helicopter turns, hover motionless and be comfortable move on to the CCR related skills such as hypercapnia, hyperoxia, hypoxia, partially flooded loop and complete flooded loop recovery, simulate electronics failure and solenoid failure in the open and closed while diving your e-ccr manually. Practice boom scenarios. As you go through all these drills remember you are planning to participate in a ccr cave course, meaning you have to do all these drills hovering, horizontally, legs up, not touching the water surface or bottom in your pool or confined water area.
Once you have honed your diver level skills and CCR diver skills as outlined above I would consider you ready to embark on a CCR cave diver training program without being overly frustrated as you have the basics down and be ready to receive CCR cave diver training to go finally cave diving. Enjoy Matt