This European Standard specifies characteristics for composite insulators for use in electric traction overhead contact lines for railways and tramways, as defined in EN 50119. Specific applications where high torsional loads can occur are outside the scope of this standard and particular tests should be agreed between the supplier and purchaser, to represent the critical loading arrangements. The provisions contained in this European Standard are for the new construction of electric traction overhead contact lines using composite insulators or when complete refurbishment of existing lines takes place. This standard provides the purchaser and manufacturer with a range of tests which are used to evaluate the suitability of an insulator product for a given railway environment. Additional tests may by specified by the client to measure the compliance of the insulator under particular operating conditions. The standard establishes the product characteristics, the test methods and acceptance criteria. The object of this European Standard is to stipulate the provisions for the sign and provision of the service indicated by the manufacturer to the pruchaser or informed buyer for application on the railway infrastructure.