Abstract: A ventilation system providing NBC protection for at least one closed security space and/or protection space with constant slight excess pressure, the ventilation system substantially having an air inlet and air outlet, an explosion protection valve, a prefilter, a filter for suspended matter, an activated carbon filter and an air conveying device for sucking in the air to be purified and for distributing the purified air, and wherein the ventilation system has at least one of the three following built-in elements: an explosion protection valve which is combined with and cooperates with the prefilter; a combined activated carbon filter made of activated carbon which is specifically effective against biological and/or chemical toxic substances, on the one hand and, on the other hand, against radionuclides; and an air pump configured as a double bellows.

Abstract: A ventilation system providing NBC protection for at least one closed security space and/or protection space with constant slight excess pressure, the ventilation system substantially having an air inlet and air outlet, an explosion protection valve, a prefilter, a filter for suspended matter, an activated carbon filter and an air conveying device for sucking in the air to be purified and for distributing the purified air, and wherein the ventilation system has at least one of the three following built-in elements: an explosion protection valve which is combined with and cooperates with the prefilter; a combined activated carbon filter made of activated carbon which is specifically effective against biological and/or chemical toxic substances, on the one hand and, on the other hand, against radionuclides; and an air pump configured as a double bellows.