Abstract: The invention relates to a method for operating a ventilation system for indoor air in an indoor space, in particular a motor vehicle. The method comprises the steps of: providing a fresh air portion of supplied fresh air and a recirculated air volume flow according to a predetermined or selected operating strategy; determining settings for a recirculated air actuator for adjusting a fresh air portion, in particular a recirculated air flap or a recirculated air valve, and a fan power of a fan for adjusting a mixed air volume flow (QM) of supplied recirculated and fresh air; increasing the fresh air portion and/or the mixed air volume flow (QM) as a function of a pathogen filtration efficiency of a cabin filter and a predetermined contamination prevention volume flow as a pathogenic indoor concentration limit value (CP) for a maximum concentration of pathogenic aerosols.

Abstract: The present invention relates to a filter medium, a filter arrangement for the filtration of gas-particle systems comprising such a filter medium, a method for depleting pathogens and/or allergens from the air and other gases by means of such a filter medium, and the use of the filter medium for depleting pathogens and/or allergens from the air and other gases. The filter medium includes at least one acid-functionalized layer comprising at least one carrier material and at least one fruit acid having a pks1 value of 0 to 7. The at least one acid-functionalized layer is free of added C8 to C18 fatty acids and their esters and amides thereof. The at least one acid-functionalized layer contains the at least one fruit acid in an amount of 2 wt. % to 30 wt. %, based on the total weight of the at least one acid-functionalized layer.

Abstract: A method includes: using a planar substrate having at least one acid-functionalized layer including at least one first acid having a pks1 value of 0 to 7 and at least one different second acid or derivative thereof selected from a group consisting of C8 to C18 fatty acids, esters, amides, and mixtures thereof, as a filter medium for depleting viruses from air and other gases.

Abstract: A filter medium includes: a functional layer; and two nonwoven layers. The functional layer is arranged between the nonwoven layers. The functional layer includes antiallergenic substances. The antiallergenic substances comprise a pourable or free-flowing solid. In an embodiment, the solid comprises a granulate. In an embodiment, the antiallergenic substances include polyphenols or fruit acids.

Abstract: In an embodiment, the present invention provides a filter element including: a bellows in the shape of a zig-zag having pleat walls and a pleat ridge, edges of the pleat walls and the pleat ridge being provided with edge elements; and a frame element being assigned to at least one end pleat of the bellows. The frame element surrounds the end pleat so as to form a positive fit on both sides, the frame element being fixed to the edge elements.

Abstract: Filter medium, comprising at least one acid-functionalized layer, characterized in that the acid-functionalized layer has a first acid with a pks 1 value of 0 to 7 and a C8 to C18 fatty acid as the second acid.

Abstract: In an embodiment, the present invention provides a filter element including: a bellows in the shape of a zig-zag having pleat walls and a pleat ridge, edges of the pleat walls and the pleat ridge being provided with edge elements; and a frame element being assigned to at least one end pleat of the bellows. The frame element surrounds the end pleat so as to form a positive fit on both sides, the frame element being fixed to the edge elements.

Abstract: Filter medium, comprising at least one acid-functionalized layer, characterized in that the acid-functionalized layer has a first acid with a pks 1 value of 0 to 7 and a C8 to C18 fatty acid as the second acid.

Abstract: An arrangement has a device which has at least one individualizing feature, detecting unit for detecting the individualizing feature, and a data storage unit in which the individualizing feature is stored and uniquely assigned to the device. The arrangement can reliably ascertain the authenticity of a product. The individualizing feature can be detected by the detecting unit and compared to the stored individualizing feature, which has already been stored in the data storage unit.

Abstract: A filter element for insertion into a housing of a ventilation or air-conditioning system, including a bellows with pleated walls and pleat tips and a front face, which can be faced towards a wall of the housing, wherein a guide duct is allocated to the front face, wherein the guide duct is formed by at least one breakthrough in the pleated walls and/or in a side strip that is hemming the front face, in view of the object to indicate a mechanical coding for a filter element which ensures a unique allocation of a filter element to a housing, wherein the filter element is provided with breakthroughs and wherein the mechanical strength of pleated walls and side strips is impaired as little as possible by the breakthroughs, characterized in that the breakthrough is provided with a reinforcing.

Abstract: A Filter element for insertion into a housing of a ventilation unit or air conditioner, comprising a bellows with folds and a front side, which can face a wall of the housing, wherein the folds on the front side define fold cross-sectional surfaces, wherein to the front side at least one guiding slot is assigned and wherein a fold cross-sectional surface has a geometry in the area of a guiding slot that is different from the fold cross-sectional surface of a multiplicity of folds, is, in view of the task of providing an efficient filter element which, after problem-free manufacture is equipped with guiding slots into which guide pins can be inserted, characterized in that a multiplicity of regular fold walls is provided, wherein each two flanking walls flank the guiding slot.

Abstract: A filter element for insertion into a housing of a ventilation or air-conditioning system, comprising a bellows with pleated walls and pleat tips and a front face, which can be faced towards a wall of the housing, wherein a guide duct is allocated to the front face, wherein the guide duct is formed by at least one breakthrough in the pleated walls and/or in a side strip that is hemming the front face, in view of the object to indicate a mechanical coding for a filter element which ensures a unique allocation of a filter element to a housing, wherein the filter element is provided with breakthroughs and wherein the mechanical strength of pleated walls and side strips is impaired as little as possible by the breakthroughs, characterized in that the breakthrough is provided with a reinforcing.

Abstract: A Filter element for insertion into a housing of a ventilation unit or air conditioner, comprising a bellows with folds and a front side, which can face a wall of the housing, wherein the folds on the front side define fold cross-sectional surfaces, wherein to the front side at least one guiding slot is assigned and wherein a fold cross-sectional surface has a geometry in the area of a guiding slot that is different from the fold cross-sectional surface of a multiplicity of folds, is, in view of the task of providing an efficient filter element which, after problem-free manufacture is equipped with guiding slots into which guide pins can be inserted, characterized in that a multiplicity of regular fold walls is provided, wherein each two flanking walls flank the guiding slot.

Abstract: A filter element includes a filter web pleated in an essentially zigzag manner and made, in particular, of a nonwoven material, for insertion into a holder such as a filter frame and/or a filter housing, having at least one end-positioned wall of an essentially flat design. The filter element includes at least one end face, viewed in the direction of the pleats. To achieve a tighter seal, the end face of the filter element is curved outward in a defined convex manner, and the filter web material is selected and/or its end face conditioned so that, when inserted into the holder, the end face of the filter web may be placed leak-tight against the end wall of the holder without corrugation under elastic pre-tension.

Abstract: A filter element includes a filter web pleated in an essentially zigzag manner and made, in particular, of a nonwoven material, for insertion into a holder such as a filter frame and/or a filter housing, having at least one end-positioned wall of an essentially flat design. The filter element includes at least one end face, viewed in the direction of the pleats. To achieve a tighter seal, the end face of the filter element is curved outward in a defined convex manner, and the filter web material is selected and/or its end face conditioned so that, when inserted into the holder, the end face of the filter web may be placed leak-tight against the end wall of the holder without corrugation under elastic pre-tension.