This European Standard specifies the material requirements and test methods for prefabricated elastomeric seals for use in flue liners. It also specifies the requirements for evaluation of conformity. These seals are components in flue liners of different materials such as metal, plastic, clay, concrete. Performance requirements of elastomeric seals in flue liners are covered by the relevant product standards. In the product standards, chimney products, including seals, are tested under operational conditions (e. g. temperature, pressure, mechanical load, flue gas, condensate) to relevant properties such as leakage and deformation. This European Standard covers seals intended for use in both dry and wet conditions. Therefore all seals are tested for functioning under wet conditions. This European Standard does not contain all the requirements necessary for chimneys with the following classification:- corrosion resistance class 2 concerning natural wood1); - corrosion resistance class 3. This European Standard is also applicable for sealants, in case nothing else is defined. The specimens are made from the sealants, which have been brought into a practical form, cured under manufacturers' instructions. The cured sealants will fulfil the same requirements as seals. NOTE Cured sealants are operationally seals in application.