This International Standard is applicable to composite insulators for use as suspension/tension line insulators, but it is to be noted that these insulators can occasionally be subjected to compression or bending, for example when used as phase-spacers. Composite insulators designed primarily to resist bending loads, e.g. line post insulators, are not included in the scope of this Standard.This standard deals with those composite insulators which include a "core" and a "housing". The core is usually made of resin-impregnated glass fibres. The housing can be manufactured from a variety of materials including elastomers (e.g. silicone, ethylene-propylene); resins (e.g. cycloaliphatic epoxy); or fluorocarbons (e.g. polytetrafluoroethylene).The object of this Standard is to: - define the terms used; - prescribe test methods; - prescribe acceptance criteria.This standard does not include requirements dealing with the choice of insulators for specific operating conditions.