FILTER FOR FIRE PROTECTION

The present invention relates to a fire protection closure for ventilation ducts having at least one package of fire protection panels extending parallel to each other in the direction of throughflow of the ventilation duct and made of a material which swells greatly in heat, the package filling the cross-section of the ventilation duct. In order to prevent a penetration of the flames or a deflagration proceeding into the next fire section during the reaction time of the swelling material, at least one insert, filling the cross-section of the ventilation duct, is arranged near to the package, which insert is filled with expanding material made of highly heat-conductive material.