A filtering assembly for air and gaseous fluids in general is provided comprising a duct, which can be crossed by a gaseous fluid carrying pollutants. The filtering assembly comprises: at least one filtering station to remove toxic gases and solid particle pollutants of dimensions preferably greater than 50 μm; at least one conductive grille, having at least one hole which faces and is proximate to at least one conductive filament being kept at a negative electric potential for the emission of electrons, which can be paired with pollutants of the solid particles and micro-organisms type of dimensions preferably between 10 nm and 50 μm, at least one accumulation plate downstream of the grille, maintained at a positive electrical potential for the stable collection of pollutants paired with the electrons at least one emission source of ions, for the restoration of electric charge of the gaseous fluid, flowing over the source.