Procedures for selecting external insulation that is likely to be subjected to an outdoor environment that includes combinations of contamination, ice, snow, or cold fog are specified by this guide. The selection methods are applicable to insulators, surge arresters, bushings, live line tools and other high voltage ac and dc apparatus with a rated voltage above 1 kV.

The guide specifies procedures for selecting external insulation that is likely to be subjected to an outdoor environment that includes combinations of contamination, ice, snow, or cold fog. The selection methods are applicable to insulators, surge arresters, bushings, live line tools, and other high-voltage ac and dc apparatus with a rated voltage above 1 kV.

The purpose of this guide is to provide methods to characterize the pollution and icing environment of a location or region and then to select outdoor high-voltage insulator types and dimensions to achieve a desired reliability level.