This page is dedicated to the development of the Dräger Tauchretter and the English DSEA (Davis Submarine Escape Apparatus). The reason this page was made is information I received from Joe. Joe is a collector of pre- and postwar Tauchretters and even owns some WWII models. In what way are Tauchretter different from normal oxygen rebreathers? Well in fact they are not. Only the intended use is different since they were used by submarine crews to save there life when they need to escape there submarine. That brings us to the point of Hyperoxia. Most of my readers are aware that breathing oxygen under high pressure can cause Hyperoxia. Commonly a limit of 6 meters depth is accepted as a safe depth when breathing oxygen. Would that be very useful when escaping a submarine?

When the unfortunate crew member has to leave his sub at 30 meters, he would be exposed to 4 bar oxygen pressure. The big difference in diving from the surface and ascending to such a depth, and leaving a submarine is the fact that the escape starts in the atmospheric hull of the submarine. The escape can be started by adding nitrogen (air) in the mix and in this way start with a Nitrox mix instead of pure oxygen. Dräger and Siebe Gorman performed many tests and were able to produce Tauchretters and  escape units capable of saving crews from depth up to 100 meter!

Later during the 60's the escape sets were equipped with Nitrox and oxygen to make escaping more safe! Strange enough the concept was not new since the 1914 DM2 unit was equipped with Nitrox and oxygen in separate bottles already!

This page shows photos of German and English training and tests performed by these brave men, and some pictures of escape units through made during many years.

If you are searching for detailed information about Dräger Tauchretters I would recommend you to visit Joe's Tauchretter pages. His website is a fantastic source for extremely detailed information about these units. He also has worth full tips how to distinguish true and fake escape sets.

The 1941 Tauchretter manual says; When escaping from 30-100 meter of depth the counterlung has to be filled with 3 breath of air. Then add pure oxygen each 5 to 10 minutes.

Sources:

1) Private photo collection
2) Joe's Tauchretter Webpage here
3) Deep Diving and Submarine operations, Sixth edition 1955, Leicester
4) Oxygen Rebreather Database, http://www.therebreathersite.nl