Deep sea diving always requires that there is enough gas to ensure a safe dive. The most common type of dive is one where a cylinder is filled with breathing gas and taken under. When this gas is finished the diver is required to resurface and refill or change the cylinder that they have. Using a rebreather eliminates the need to dive with an excess of gas. This is because it recirculates the air that the diver has already used, replacing his emitted carbon dioxide with oxygen in the correct amounts for breathing.

Advantages of Rebreather Diving

1. Long Dive Times

The only equipment that is needed is one filled cylinder and a carbon dioxide scrubber. This one fill can last anywhere between one and six hours, and be used for several dives. The length of time that the gas lasts is not affected by how deep the dive is, because rebreathers are designed to add gas for increased depth and take it away as the diver enters more shallow waters.

2. Limited Bubbles

Regular diving cylinders produce many bubbles when the diver breathes. This can be disadvantageous as the bubbles alert the marine life to the divers approach, as well as fill small areas in wrecks with air and dislodge loose areas in caves.  Rebreather diving is relatively silent and bubbles are normally only produced on ascent. This is one of the main reasons that marine biologists and photographers use rebreathers in their work and research.

3. Warmer Air

As a result of the chemical reaction caused in removing carbon dioxide, the air that is produced by the rebreather is warm and moist. This helps to regulate the divers’ body temperature, as well as reduce the cotton mouth feeling that is caused by diving with regular cylinders.

4. Optimum Air Mix

Rebreathers constantly monitor the air mix of the gas that is being taken in by the diver to ensure that it is ideal for humans.

Disadvantages of Rebreathers

1. Failure might not be Immediately Noticed

The most important part of keeping the gas breathable in a rebreather, is ensuring that the carbon dioxide is removed when the diver breathes out. When one fails it means that the division of air has become inappropriate for use. The only immediate indication of this will be shown on the equipment’s monitors, which the diver will need to be constantly paying attention to, as carbon dioxide and oxygen mixed in the wrong amounts can be fatal.

2. Equipment

Rebreather equipment is normally bulkier and heavier than regular cylinders, and until divers get used to using it they may find that it is harder to operate and maintain. Higher quality equipment is also more expensive.

Originally used in military, scientific and technical dives the popularity of rebreather diving has extended to recreation because of the convenience of longer and quieter dives, and will probably keep doing so as more people begin to realize its benefits.