This standard covers metal-enclosed interrupter (MEI) switchgear assemblies containing@ but not limited to@ such devices as interrupter switches; selector switches; power fuses; control@ instrumentation and metering devices; and protective equipment. It includes@ but is not specifically limited to@ equipment for the control and protection of apparatus used for distribution of electrical power.This standard is concerned with enclosed (rather than open)@ indoor and outdoor switchgear assemblies rated above 1000 V. It includes equipment that is part of primary and secondary unit substations. It does not include gas-insulated substation equipment nor switching devices mounted integrally within a transformer enclosure.