Dual hose configuration
The most characteristic external feature is that a rebreather user uses a breathing hose with an inlet and an outlet. With the exception of oxygen rebreathers, almost all modern rebreathers have separate counter lungs and separate hoses for supply of oxygen-rich gas and removal of Co2-rich gas. By using two hoses, a circuit is created and, with the help of valves, a gas flow direction is realised. The valves are often integrated in the mouthpiece, but can also be mounted on the scrubber. The hose diameter, together with the scrubber, largely determines breathing comfort and breathing resistance. The mouthpiece must be lockable. For systems designed for underwater use, an ABV (ambient breathing valve) is desirable. For underwater use, different systems are designed to switch from the closed system to open circuit breathing.
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!