Rebreather Frequently Asked Questions
What is a rebreather?
Rebreathers are diving systems that recycle your breathing gas. It is a machine that recycles your exhaled gas so that it can be used again.
What are the advantages of diving a rebreather?
Gas efficiency, reduction in decompression, bubble silence (noise reduction), and no dry air to breathe. By recycling your exhaled gas, filtering out the CO2, and passing along the oxygen for reuse, the amount of gas you carry goes a long way. The reduction in decompression ONLY applies to a CCR type rebreather. By maintaining constant PPO2 levels within the system throughout an entire dive, you can reduce decompression obligations. Rebreathers, because they vent only small amounts of bubbles or no bubbles at all are much quieter under the water. You don’t hear regulator valves opening or air traveling through a hose or the exhaled bubbles when they exhaust into the water. Rebreathers are very quiet underwater. Open circuit diving requires compressed, dry air in a cylinder, that when breathed, is also very dry and can cause a dry mouth or throat and dehydration. Rebreathers operation of removing CO2 from your exhaled gas is a chemical reaction that creates heat and moisture. This moisture is passed along to the breathing gas and thus to you. When diving a rebreather, you get to breathe warm, moist gas, which is more comfortable than the dry air from a cylinder.
What are the disadvantages of diving a rebreather?
Discipline, training requirements, and the cost. There is more discipline that is required when diving a rebreather as opposed to open circuit. O2 levels must be monitored, bailout systems must be in place, maintenance is increased, and diver awareness must be heightened. The bottom line is that there is more to diving a rebreather than open circuit. Training requirements are also increased due to the complexities of rebreathers, especially CCRs. Training can vary from rebreather to rebreather because of operation differences, configurations, etc. Training courses are also more lengthy than open circuit courses, meaning you need to set aside more time. Finally, the cost of rebreathers can reach into the many thousands of dollars. The expense alone can tough to deal with. For these reasons, diving rebreathers is not for everyone.
Do you need a special certification to dive a rebreather?
You need special training to dive a rebreather and thus, many training agencies offer a certification card along with their training course. Rebreather training is very specific to the model of rebreather as well as whether it’s a SCR or CCR. Extensive training is required for any type of rebreather before diving one on your own.
Do you need special equipment to dive a rebreather?
A rebreather is a specific piece of equipment in itself, meaning that it must be purchased as a unit. You can still use your same exposure suit, fins, mask, etc., but your open circuit configuration goes away.
How much does a rebreather cost?
Rebreathers can cost between $2,000 and $30,000, which means that you don’t want to jump right in and buy the first one you see. You need to make sure that the rebreather you purchase meets your needs, operates the way the manufacturer says it does, and is reliable and durable enough to last you many years.