This is a detailed overview of JJ CCR rebreather, which is divided into several parts, covering both the device's construction, testing reviews, and frequently asked questions for the trainer of the underwater diving club "Daivings.lv". Apply and try eCCR CE Rebreather with an instructor (Introduction to rebreather diving).
JJ CCR rebreathers are designed to be some of the most durable and robust rebreathers in the world, often referred to as the “4×4” of the rebreather world. Their design is based on the principle of simplicity, with a minimum number of parts that can fail. This means that the JJ CCR is highly reliable and resistant to accidental damage.
The JJ CCR is not exactly an evolution of the Inspiration rebreather, although the first JJ model was actually the Inspiration Classic encased in an aluminum box. This design approach made for easier diving and easier equipment attachment. The JJ CCR was designed by Danish diver Jens Bout, who created it based on his diving experience in the Baltic Sea.
Table of Contents
Rebreather construction
The JJ CCR consists of several main parts:
- Aluminum box: A very durable, one-piece aluminum box that houses the main components of the rebreather.
- Base: Made of Delrin material, which is durable and lightweight. The base serves to hold the rebreather upright, and some divers also use it to attach additional equipment.
- Handle: A durable Delrin handle is attached to the aluminum case with two screws. The handle allows for easy movement of the rebreather, even when fully assembled and loaded with weight.
- Mounting points: The box has several mounting points for attaching various accessories, such as a light canister or a wetsuit inflation cylinder.
- Scrubber: Contains an absorbent that removes carbon dioxide from exhaled air. The scrubber is made of two parts – the white part contains the absorbent, and the black part is a mixing chamber where oxygen is added and the gas mixture is analyzed.
- Balloons: JJ CCR uses two cylinders – one with diluent (usually air or nitrox) and one with oxygen. The cylinders have separate valves to prevent accidental mixing.
- Regulators: Two small regulators designed to supply diluent and oxygen. The regulators have pressure relief valves to prevent overpressure in the hoses during diving.
- Wings: Simple fenders with holes for hoses to exit. The fenders also have mounting points for attaching a SPG (pressure gauge).
- Contour lips: Internal contour lips made of durable material. Contour lips have two manual connection valves – one for diluent and one for oxygen.
- Back plate and straps: Standard 11" back plate with adjustable straps. The straps are equipped with D-rings and attachment points for additional equipment.
- Head: The most important and complex part of the rebreather, which houses the electronics, oxygen sensors, and solenoid. The head is responsible for adding oxygen and analyzing the gas mixture.
- Controller: A hand-held controller that allows the diver to control the operation of the rebreather and monitor oxygen levels.
- HUD (Head-Up Display): LED display showing the partial pressure of oxygen in the rebreather.
Testing and reviews
The JJ CCR has been thoroughly inspected and tested to ensure its reliability and safety. A number of checks must be performed before each dive, including:
- Positive and negative test: Checks the tightness of the contour lips and hoses.
- Calibration: Ensures that oxygen sensors are working properly.
- Pre-breathing: Tests the operation of the rebreather and allows the diver to get used to breathing through the rebreather.
The JJ CCR has received positive reviews from divers, who praise it for its simplicity, reliability and durability. The rebreather is easy to assemble and use, and is suitable for both beginners and experienced technical divers.
Frequently asked questions
- What is the price of JJ CCR? The price of the JJ CCR is approximately 7,190 euros, excluding shipping costs.
- What is the price of training? The price of training is approximately 800-1000 euros.
- What is the maintenance interval for the JJ CCR? First stage regulators should be serviced annually, while rebreather major maintenance should be performed every two years.
- Are there different models available for the JJ CCR? The JJ CCR is available in only one model, but it can be slightly modified to suit individual needs.
- What is the JJ CCR warranty? The JJ CCR has a two-year warranty.
Summaries and conclusions
The JJ CCR is a high-quality rebreather that offers exceptional reliability, durability and simplicity. It is a great solution for both beginners and experienced technical divers looking for a safe and easy-to-use rebreather.
Rebreathers offer several advantages over open-circuit diving equipment:
1. Efficiency and longer dive time: Rebreathers recycle exhaled air, removing carbon dioxide and adding oxygen. This means no gas is wasted and a diver can stay underwater longer with fewer cylinders.
2. Warmer and more humid air: The rebreather retains the moisture in the exhaled air, providing the diver with warmer and more humid breathing air. This reduces the risk of dehydration and helps maintain body temperature.
3. Quieter operation: Rebreathers are much quieter than open-circuit diving equipment because they do not create bubbles. This is especially important for observing marine life and underwater photography.
4. Deeper diving: Rebreathers allow divers to reach greater depths because they can optimize the gas mixture depending on depth.
5. Less gas requirement: Rebreathers require less gas than open-cycle equipment, meaning a diver can carry fewer cylinders or stay underwater longer with the same number of cylinders.
6. Reducing the risk of dehydration: By breathing warm and humid air, a diver loses less fluid, reducing the risk of dehydration.
However, rebreathers also have some disadvantages:
1. More complex maintenance: Rebreathers require more careful maintenance and regular inspection than open-cycle equipment.
2. More expensive: Rebreathers are more expensive than open-circuit diving equipment.
3. Special training required: Divers who want to use rebreathers must obtain special training and certification.
JJ CCR rebreathers have several advantages over other rebreathers:
1. Simplicity and reliability: The JJ CCR is designed with simplicity in mind, with a minimum number of parts to fail. This makes it one of the most reliable rebreathers on the market, with less risk of failure and easier maintenance.
2. Durability: The JJ CCR is made from durable materials such as aluminum and Delrin, making it highly resistant to damage. This is especially important in technical diving, where the equipment is subjected to high stress.
3. Easy to use: The JJ CCR is easy to assemble and use, even for divers with limited experience. Its simple design and intuitive controls make it a great choice for both beginners and experienced technical divers.
4. Modular design: The JJ CCR has a modular design that allows it to be customized to individual needs. For example, a diver can choose between standard and extended range canisters, as well as different scrubbers with different run times.
5. Long maintenance intervals: The JJ CCR has relatively long maintenance intervals – first stage regulators require annual maintenance, while the rebreather requires major maintenance every two years. This reduces maintenance costs and ensures a longer service life.
6. Availability: The JJ CCR is a relatively affordable rebreather compared to other models available on the market.
More detailed answers with numbers:
- Weight: Approximately 33-35 kg fully assembled.
- Scrubber operating time: Standard axial scrubber – 3 hours; Radial scrubber – up to 6 hours (depending on model).
- Maximum diving depth: 200 meters (CE certified).
- Maintenance intervals: First stage regulators – every year; Major maintenance – every 2 years.
- The price: Approximately 7,190 euros (excluding taxes and shipping costs).
Comparison with other rebreathers:
The JJ CCR is lighter than many other rebreathers, such as the Inspiration and rEvo. It is also more durable and has a simpler design, which makes it easier to use and maintain. The JJ CCR also has longer maintenance intervals than many other rebreathers, which reduces maintenance costs.
However, the JJ CCR is not as modular as some other rebreathers, such as the rEvo, which allows you to change almost every part of the rebreather. The JJ CCR also has a limited maximum dive depth of 200 meters, compared to 300 meters for the rEvo.
Overall, the JJ CCR is a great option for divers looking for a reliable, durable, and easy-to-use rebreather at a relatively low price. It is especially suitable for technical divers who value simplicity and reliability.
Gas planning with a rebreather is different from open-circuit diving and has its own characteristics that must be taken into account.
Partial pressure of the breathing mixture:
- The main purpose of a rebreather is to maintain an optimal partial pressure of oxygen (ppO2) in the breathing mixture. This is achieved by automatically adding oxygen to compensate for the oxygen consumed and absorbing exhaled carbon dioxide.
- Optimal ppO2 depends on the depth of the dive and the individual needs of the diver. It is usually maintained in the range of 0.4 to 1.6 ATA (atmospheric absolute pressure).
- Too low a ppO2 can cause hypoxia, while too high a ppO2 can cause oxygen toxicity.
Nuances of gas planning:
- Dilute selection: Unlike open-circuit diving, where the diluent is the ambient environment (water), in rebreather the diluent can be air, nitrox or trimix. The choice of diluent depends on the depth of the dive and the planned dive time.
- Oxygen sensors: Rebreathers use oxygen sensors to monitor the ppO2 in the breathing mixture. It is important to calibrate the sensors regularly and ensure that they are working properly.
- Contour lips: The rebreather has contour lips that serve as a gas reservoir. The volume of the contour lips must be adjusted to the depth of the dive to ensure comfortable breathing.
- Training: It is important to obtain proper training in the use of rebreathers and gas planning to ensure safe diving.
Other nuances:
- Carbon dioxide absorption: Rebreathers use absorbents to separate carbon dioxide from exhaled air. It is important to change the absorbents regularly and make sure they are not saturated.
- Humidity control: Rebreathers maintain the humidity of the breathing mixture, which helps prevent dehydration and reduces body heat loss.
- Bailout gas: Rebreather divers must have bailout gas available (usually open-circuit diving equipment) to use in emergency situations if the rebreather is not functioning properly.
Gas planning with a rebreather is more complex than in open-circuit diving, but it also offers several advantages, such as longer dive times, warmer and more humid breathing air, and quieter operation. Before diving with a rebreather, it is important to obtain appropriate training and carefully plan the dive, taking into account all the nuances.
