Oxygen generating module

A multi-chamber permselective apparatus for providing oxygen enriched filtered air matched to a range of breathing rates, comprising

• a first chamber containing microcapsules comprising an oxygen generating compound as a core material and a coating which is moisture swellable but not soluble, said coating slowly exposing said core material to moisture in respired air, said core material reacting with the moisture and generating oxygen;
• a second chamber containing a solid carbon dioxide absorber for absorbing carbon dioxide from respired air;
• a third chamber containing an aqueous solution of a mildly acidic salt and a nonionic surfactant;
• a fourth chamber containing aqueous hydrogen peroxide and a nonionic surfactant,
• said chambers being made from a semi-permeable fabric, said fabric preventing fluid penetration under normal pressure but allowing fluid to pass through under moderate over-pressure,
• a first pressure means comprising a first plunger and a first frangible disc, said first plunger being attached to said third chamber and said first frangible disc separating said aqueous solution of mildly acidic salt from a porous wall of said first chamber, a first level of oxygen generation being activated by depressing said first plunger to rupture said first frangible disc, wherein subsequent to said rupture of said first frangible disc a repeated depression of said first plunger resulting from a first breathing rate causes an increase of pressure, thereby increasing a flow of said aqueous solution of mildly acidic salt through said porous wall and into said first chamber
• a second pressure means comprising a second plunger and a second frangible disc, said second plunger being attached to said fourth chamber and said second frangible disc separating said aqueous hydrogen peroxide from said porous wall of said first chamber, a second level of oxygen generation being activated by depressing said second plunger to rupture said second frangible disc, wherein subsequent to said rupture of said second frangible disc a repeated depression of said second plunger resulting from a second breathing rate causes an increase of pressure, thereby increasing a flow of said aqueous hydrogen peroxide to pass through said porous wall and into said first chamber.