ABSTRACT
This chapter deals with a summary of application data concerning ceramic insulators after which the nonceramic insulator is considered. The terms contamination and pollution, like the terms leakage and creepage, are used as synonyms. For transmission or distribution lines, contamination dictates the type of insulator and the length of the insulator string. In some contamination areas, the insulator length may exceed that required by lightning or switching surges, and therefore the final design of the line is based on contamination. In some parts of the USA and in some countries, contamination is the dominant design criterion, dictating the design of the line or station insulation. However, fortunately, for most of the world, contamination is not present to the degree that the insulation requirements overshadow the requirements of switching and/or lightning. One method of determining the insulation required that obviates, to a degree, the measurement of contamination is the construction of test stations along the proposed right-of-way.
