Rebreathers

If you want to stay underwater longer, you don’t need a crane to get into the water. What you need is a KISS Rebreather!

Rebreathers were created for mine rescue work in the 1800s and later became an important tool in submarine rescue operations and for other military purposes.

Nowadays, rebreathers are popular with the technical caving community and also for underwater photographers and wreck divers. Being able to stay longer, with less decompression obligation – and no bubbles, is fantastic.

Recreational rebreathers are categorised into:

Fully closed (CCR) and
Semi-closed (SCR).

CCRs are further categorised as electronic or manual CCRs. An eCCR is controlled by an electronic solenoid while the eCCR is controlled by the diver. The KISS Sport, Classic and Explorer CCRs are all manual.

The principle of the KISS rebreather is that oxygen and a diluting (Diluent or Dil) gas such as air or trimix are fed into a loop hose that has one way valves in it to control the direction of gas flow. A diver’s exhaled breath passes through a CO2 absorbent material and the CO2 is removed. A very small flow of oxygen replaces this CO2 in the loop volume. The correct amount of oxygen is calculated easily by monitoring the partial pressure of oxygen in the loop (PO2) using oxygen sensors. If it gets too low, more oxygen can be injected. If it gets too high, it can be diluted by injecting Dil.

The end result is that the diver breathes the optimum percentage of Nitrox at every depth thus reducing the level of nitrogen at every stage of the dive. This means longer safer dives – with no bubbles to scare the fish or dislodge silt in wrecks and caves.