Abstract: A laminarizer or arrangement for producing laminar flow, particularly for ceilings and walls of clean rooms or the link formed of filter modules. The laminarizer is suspended or held spaced from a cover supporting mechanical filters. The laminarizer is composed of rectangular frames with fabric sheets stretched onto the rectangular frames. The side members of the rectangular frames are hollow sections or angle sections of triangular cross-section. The fabric sheets rest against and are aligned by the surfaces of the side members facing the rooms are only as narrow and/or rounded-off alignment contacts for the fabric sheets, while the fastening of the fabric sheets is provided at the outer surfaces of the side members extending perpendicularly to the plane of the frame and/or on the rear surfaces of the side members extending in the plane of the frame.

Abstract: Damper for the protection of equipment, through which a gaseous or vaporous medium, particularly air, flows, against pressure waves, particularly in ventilation and/or air conditioning installations for the protection of the components of the plant, its internals and ducts, consisting of a frame structure and a multiplicity of slats (15) which are supported therein hinged about parallel axes and in one plane and which are held in their open position by restoring forces and are braced against stops.