Single bag type counterlung
Most oxygen rebreathers use a simple single counter lung. Materials used in the early days are finely-woven fabrics, impregnated with rubber or latex. Later reinforced plastics where used. These plastics are commonly welded by induction techniques. Also rubber moulded lungs are used, although the reliability still has to be proved.
The counter lung volume varies tremendous. There are models with a 4 liter up to 17 liter volume. Bigger volumes are employed when the CL is also used as the main BCD, or life safer.
The single counterlung is often in line with the scrubber, so there is an inhalation and exhalation hose. The lung collects the exhaled gas outside the diver or carrier. Earlier models almost always had a scrubber in the long that was breathed through.
Therebreathersite was founded by Jan Willem Bech in 1999. After a diving career of many years, he decided to start technical diving in 1999. He immediately noticed that at that time there was almost no website that contained the history of closed breathing systems. The start for the website led to a huge collection that offered about 1,300 pages of information until 2019. In 2019, a fresh start was made with the website now freely available online for everyone. Therebreathersite is a source of information for divers, researchers, technicians and students. I hope you enjoy browsing the content!