Secondary arresters have been used since 1940 to protect the secondary winding of distribution transformers, kw.h meters, and electrical loads downstream from breakdown of insulation during lightning strikes. Performance criteria for secondary arresters are included in standards for performance of high voltage arresters IEEE C62.1-1989 and IEEE C62.11-1993. With the proliferation of electronic equipment installed inside buildings, the emphasis has shifted away from protection of insulation on wiring devices to vulnerable electronic equipment. The purpose of this standard is to address that changed emphasis while, as far as possible, harmonizing with relevant international standards.