1. Long dive times.
The biggest advantage of a rebreather is gas efficiency. A single fill of a small gas cylinder or cylinders and CO2 scrubber can last for anywhere from one to six hours, depending on which rebreather it is. Unlike open-circuit scuba, your gas duration on a rebreather is nearly independent of depth, so you could, in theory, spend all that time on the bottom.
Of course, a rebreather does not make you immune to DCS and nitrogen narcosis. Those risks remain, though the more sophisticated closed-circuit rebreathers, such as the JJ-CCR can adjust your gas mix to reduce the DCS risk. The advantage of the rebreather’s long duration for most of us is that you can make several dives on one fill of absorbant and cylinders.
Rebreathers exhaust few or no bubbles. You don’t hear that roar of exhaust bubbles, and neither do the fish. That allows you to get closer to marine life, which is why rebreathers are popular with professional photographers and some researchers. You won’t be rendered invisible, but you seem to be less alarming to most fish.
3. Warm, moist breathing gas.
The chemical reaction in the CO2 scrubber actually warms and humidifies your breathing gas. Diving with a rebreather does not give you that cotton-mouth feeling and doesn’t chill you as much.
4. Optimum gas mixture.
The more sophisticated rebreathers constantly monitor the partial pressure of oxygen in your breathing mix. They can keep your PPO2 constant regardless of depth or exertion, or alter it on the fly for needs like decompression. The benefit can be less nitrogen uptake and faster offgassing–in other words, more bottom time with less DCS risk. Rebreathers are not created equal, however, and the less-expensive designs do not have this ability.
1. THE JJ-CCR
The JJ-CCR rebreather has been called ‘the 4 x 4 of the rebreather community’ which in many ways is the perfect description as it is built for all types of terrain and can be adapted to handle the most demanding adventures. The JJ-CCR demands a skilled diver fully aware of the pros and cons of technical rebreathers and was never intended for the sports diving market, it was engineered by professional wreck divers who needed a solid tool to do the job in the deep, dark, and cold waters of the Baltic Sea. The environment the JJ-CCR was built for demands a rebreather that is simple and sturdy in regards to handling and ruggedness, independent of the situation and operational environment. All of the components of the JJ-CCR have been carefully selected and are there for a reason! Each detail has a purpose and every solution can be justified. The versatility of the rebreather makes it adaptable for whatever dive you are planning.
The philosophy behind the JJ-CCR is to keep it simple with robust construction and minimalistic work detail making it easy to handle before, during and after the dive. The main assembly consists of an aluminium housing and a stainless steel stand where all the components such as counter lungs, wings, and harness are attached. This provides the user with comfort on land when donning the rebreather as well as in water when diving it. All hoses and gas paths are made for optimal performance both in water and for maintenance purposes. The JJ-CCR is equipped with state of the art electronics and is ready to fly right out of the box.
The JJ-CCR is equipped with a state of the art electronics package. It has a redundant power supply with one battery for the controller, one battery for the HUD and two parallel batteries for the solenoid. None of the batteries are integrated into the breathing loop. It has a DiveCAN® communication interface for robust data transmission and easy upgrades, disassembly and repairs. The JJ-CCR has wet contacts for automatic turn-on. The JJ-CCR is equipped with a reliable controller with an integrated multi-gas decompression computer – the Shearwater Petrel2. It has an independent HUD (Head Up Display) with real-time display of PPO2 for all three oxygen sensors.
3. THE BREATHING LOOP
The JJ-CCR has an industry low work of breathing. With its back mounted counter lungs that follow the contours of your shoulders, it will help you to keep a smooth and comfortable breathing pattern. T-pieces milled out of Delrin connect to heavy duty breathing hoses that end in a sturdy DSV (Dive Surface Valve). The breathing loop has an integrated ADV (Automatic Diluent Valve).
4. SCRUBBER DESIGN
The standard scrubber unit on the JJ-CCR is an axial scrubber. It holds 2.5 kg sodalime (sofnolime 797). The scrubber unit is easy to lift out of the canister as the attached lid has a lifting handle on top. The scrubber is attached to the lid by a heavy duty thread. The construction of the scrubber, lid and canister makes re-packing of scrubber as well as surface interval maintenance an easy task!
5. CANISTER AND STAND
The canister is made from hard anodized aluminum and has 4 welded consoles for the attachment of tanks and/or light canisters, etc. The canister has two cylinders that can be filled with compensating weights if needed. The lift handle that is located on top of these cylinders can be lowered to minimize the height of the construction. The stand which is bolted in the bottom of the canister is made from stainless steel and gives stability and comfort to the user while handling the rebreather on land.
6. PLATE AND HARNESS
The JJ-CCR is equipped with a fully adjustable harness designed specifically for the JJ-CCR. The harness is padded in the shoulder and chest area which provides the user with great comfort. The harness is designed with numerous equipment D-rings so that the user can configure equipment according to task.
The JJ-CCR is a versatile rebreather built for every dive you have in mind. The canister is equipped with 4 sturdy consoles, designed and placed so that diver and team can configure their JJ-CCRs for maximum exploration output.