The standard describes the terms and definition, use condition, technical requirement, and test methods of composite post insulators for high-voltage direct-current (HVDC) power transmission systems up to ±800 kV. This standard applies to outdoor and indoor composite station post insulators used in HVDC power transmission systems. The composite station post insulators covered by this standard consist of a load-bearing insulating core (or tube), a housing (outside the insulating solid core or tube) made of elastomer material (e.g., silicone or ethylene-propylene), and end fittings attached to the insulating core (or tube). This standard covers the following three types of post insulators: a) Composite post insulator with a ceramic core; b) Composite post insulator with a resin impregnated fibers solid core; c) Composite gas-filled hollow post insulator