Applies to aerial devices (mobile elevating work platforms (MEWP)), with or without the possibility of an additional jib, as a minimum with an insulating upper boom (extending structure) used for live working on the rated voltage, which is between 1 kW r.m.s. and 800 kV r.m.s., at power frequency. The contents of the corrigendum of July 1999 have been included in this copy.