EN 50290-2-X contains, in its various parts, the requirements for polymeric insulating, sheathing and covering materials that are used for metallic and optical fibre cables (Table 1). The materials to be used for EN standardised communication cables are not, and will not be, restricted only to those defined (Table 1). New materials for cables will be described in further parts of the series. The current structure of the EN 50290-2-NN series is outlined in Annex A. Furthermore, the use of materials described in the EN 50290-2-NN series for other cable applications outside those defined (Table 1) is not prohibited, but it is strongly recommended that expert advice be taken before such use, or before any proposal for incorporation into another standard.