Hi there, CCR divers! If you've taken the plunge into rebreather diving (CCR), you know that your machine relies on a delicate balance. At the heart of this system lies a vital element, often nicknamed the "chemical lung" of the rebreather: Sofnoline.
Discover how to properly store sodalime, ensure its traceability, and master its entire life cycle.
Physiologically, we inhale a mixture of nitrogen and oxygen. When we exhale, our body rejects carbon dioxide ($CO_2$). In an open circuit system, this CO2 is simply expelled as bubbles.
In a rebreather, the gas circulates in a closed loop. For this gas to remain breathable and non-toxic, the $CO_2$ must be removed before it is re-enriched with oxygen and inhaled again. This is where sodalime comes in: it has the property of chemically fixing ("absorbing") carbon dioxide.
It is this recycling process that makes your dives so long and silent! However, be careful: its lifespan is limited, so it is crucial to always have fresh sodalime to dive with peace of mind.
SOFNOLIME 797 is the most widely used sodalime for diving rebreathers. If you see 20kg kegs of Sofnolime 797 in specialized dive centers, it’s no coincidence. This grade is compatible with almost all machines on the market.
It is recommended by the leading rebreather brands such as Triton, rEvo, AP Diving Inspiration, Megalodon, CCR Liberty Divesoft, Poseidon Discovery MkVI, rEvo rebreathers, Shark Rebreathers, Innerspace Systems Corp Megalodon, Pathfinder, etc.
SOFNOLIME 797 is a carbon dioxide absorber that removes CO2 during AIR, NITROX, or Heliox dives. SOFNOLIME grade 797 consists of 1mm to 2.5mm particles with a triangular cross-section, providing a high absorption capacity.
Granulometry (1.0mm to 2.5mm): its specific grain shape offers an optimal exchange surface while ensuring breathing comfort (low work of breathing/resistance).
Dust Management: Sofnolime is extremely rigid, which limits dust formation during transport or filling, thus protecting your lungs and your valves.
Sodalime has a limited absorption capacity. Once saturated, it no longer filters CO2, leading to a risk of hypercapnia (shortness of breath, narcosis).
How to store sodalime: buying in 20kg kegs is economical, but make sure to seal the container tightly after each use. Sodalime is sensitive to ambient humidity and prolonged air exposure. Sodalime saturated with moisture loses its filtration capabilities. Conversely, well-stored sodalime can be kept for several years (generally two years from the manufacturing date).
Packing (Scrubber): This must be done with care. Poor packing can create "channeling" (where gas passes around the grains without being filtered).
Traceability: systematically log your sodalime usage time. Never exceed the manufacturer's recommendations, as efficiency drops drastically at the end of the cycle or in cold water. Dive computers help you track this. Connected dive computers, like the Shearwater Petrel, allow you to reset and monitor scrubber time.
Need to restock? Find our latest arrival of sodalime on Diveavenue.com order sofnolime here