Siva is a model series of of frogman's rebreather made by Carleton Life Support. They are:
- Siva S10 oxygen rebreather, dive duration 4 hours. Worn on the front of the chest.
- Siva S24, usable as oxygen rebreather, or as a semi-closed circuit mixed gas rebreather with maximum depth normally 24 meters, can be set to 55 meters. Worn on the front of the chest.
- SIVA-55 (technical data, images) and SIVA PLUS: superseded by the Carleton Viper. They are worn on the back.
The Siva is equipped with 400 bar titanium spheres with a total volume of 5.6 liters. The Siva 55 (55 mtrs of depth) works with any one of 3 Nitrox mixes (32.5, 40 and 60 % Oxygen) or pure oxygen. The pure oxygen is used for closed circuit diving so the diver can work without bubbles. The other Nato standard B,C and D mix are standard nitrox mixes used in semiclosed-circuit mode. The SIVA + is a selfmixing rebreather. It works on another principle. A constant flow of oxygen is mixed with a diluent volume dependent on the ambient pressure. The deeper the diver dives, the more diluent is added, the leaner the mix is. The correct setpoint is controlled with a partial pressure measuring device (electronic). The SIVA + is capable for diving to 90 mtrs. Diluent can be air, trimix or heliox.
