So what is a Closed Circuit Rebreather (CCR) ?
In contrast to conventional scuba or open circuit where most of the breathing gas is wasted on exhalation into the surrounding water, Closed Circuit Rebreathers are fully closed circuit systems in which all of the exhaled breath is retained within a closed loop. It is then filtered and refreshed and recycled back to the diver for further use. Only during ascent and mask clearing are bubbles emitted.
Mixed Gas Diving – The oxygen controller automatically maintains a constant partial pressure of oxygen in the breathing loop and thereby delivers a variable fraction of oxygen, in other words, an oxygen-rich mix throughout the dive (dependant on your depth) and a super-rich mix during decompression. This allows you to stay at depth for longer (dramatically increased no-stop times) and benefit from shorter decompression stops. No Bubbles – Bubbles are the enemy of any underwater photographer for both disturbing photos and scaring away underwater life. With a CCR, there are no bubbles and therefore no noise to scare away any wildlife allowing you to get centimetres away from them for that perfect picture.