Was an Austrian biologist and underwater diving pioneer. He was one of the first scientists to familiarize the underwater world to the public. Stingrays, sharks and coral reef where among the regular subjects of his photographs and films. He pioneered the making of documentaries filmed underwater.
He works with Dräger during the II World War, a German rebreather manufacturer. Michel Jung divulged that Dräger was told to work with Hans because his research was officially defined as “important for war”; specially for finding new food for the people and finding new methods catching fish and fish farming.
The rebreather unit owned and modified by Hans was small, fastened to the belt was an oxygen bottle. This had an automatic control valve with constant oxygen flow. The counterlung was on the bag of the shoulders.
The diver inhaled from the bag throughout a corrugated tube with a mouthpiece, and the exhaled air went to an absorbent cartridge to clean the CO2. The cartridge could be opened and sealed again to be filled with fresh lime before a dive.
At the time, no one agreed on depth limitations when breathing oxygen, but Dräger that 6 meters should not be exceeded.
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