Siebe Gorman Salvus

The Siebe Gorman Salvus is a light oxygen rebreather for industrial use (including by firemen and in coalmine rescue) or in shallow diving. Its duration on a filling is 30 to 40 minutes. It was very common in Britain during World War II and for a long time afterwards. Underwater the Salvus is very compact and can be used where a diver with a bigger breathing set cannot get in, such as inside cockpits of ditched aircraft. It was made by Siebe Gorman & Company, LTD in London, England. It was designed in the early 1900s.

Its arrangement can be seen from the image. It is a pendulum-type system with one breathing tube. This type is the Neck Salvus: there was another type, for use on land only, where the counterlung (= breathing bag) hung by his left hip from the cylinder and canister pack. That pack is a metal plate (probably aluminium), with a webbing sheet stuck to one side to protect its user's diving suit or overall. The absorbent canister and the cylinder are fastened to it by a strap that can be unbuckled. It has no plastic in its construction.

The mask has an inner orinasal mask to cut down on dead-space. It does not have a shutoff valve. It has a wooden plug fastened to it by a light chain; that plug fits into the breathing tube entry inside the mask to stop debris from entering, but is not a watertight seal. The mask and its tube unscrews from the canister and can be replaced by a tube ending in a mouthpiece. The mouthpiece tube has a shutoff valve at the mouthpiece. The Salvus mouthpiece also has an attached noseclip. A pair of industrial-type eyes-only goggles was included with the set when it came. That mouthpiece has an outer flap that goes outside the lips and is extended into straps fastened behind the neck.

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