Dräger model BG 170-400
The successor to model BG 160
The Dräger BG 170/400 is a special breathing device for miners. It lets them breathe fresh gas even in dangerous environments because it recycles the gas they exhale. Unlike older models like the BG 1924 and BG 160A, which delivered a constant amount of oxygen, the BG 170/400 provides oxygen only when the wearer breathes in. This automatic system, along with a bigger supply of oxygen (400 liters compared to 300 liters), allows miners to work for much longer. At rest, the BG 170/400 lasts up to 18 hours, while it provides 5 to 7 hours of breathing time for working miners. This innovative device is the result of 4 years of development, which included creating 15 different prototypes before reaching the final design. The Dräger BG 170/400 is a widely used piece of equipment in the Dutch mining industry.
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!