Is applicable to composite string insulators with a specified mechanical load (SML) of 40 kN and 70 kN for a.c. overhead distribution lines with a nominal voltage greater than 1 000 V and a frequency not greater than 100 Hz.It also applies to insulators of similar design used in substations or on electric traction lines.This consolidated version consists of the first edition (1998) and its amendment 1 (2002). Therefore, no need to order amendment inaddition to this publication.