Provides recommendations for the selection and application of surge arresters to be used in three-phase systems with nominal voltages above 1kV. It applies to non-linear resistor type gapped surge arresters as defined in IEC 60099-1 and to gapless metal-oxide surge arresters as defined in IEC 60099-4. The contents of the corrigendum of April 1996 have been included in this copy. This consolidated version consists of the first edition (1996) and its amendment 1 (1999). Therefore, no need to order amendment in addition to this publication.