This standard describes the tests to be prepared on composite insulators for applications above 70kV, and defines the acceptance criteria for such tests. See 3.1.1 for the definition of a composite insulator. All hitherto published American National Standards in the C29 series are for insulators made of wet-process porcelain or toughened glass.

The standard includes definitions pertinent to composite insulators. It introduces a new category of tests called prototype tests, designed to evaluate the materials and construction of composite insulators. Prototype tests are expected to be be performed on representative samples but may be performed prior to the start of production.