Requirements and guidance for the seismic qualification of metal-enclosed power switchgear assemblies including switching, interrupting, control, instrumentation, metering, and protective and regulating devices mounted therein are provided in this guide. As used in this guide, the word switchgear shall mean metal-enclosed power switchgear assemblies with the requirements as defined in IEEE Std C37.20.1™, Standard for Metal-Enclosed Low-Voltage Power Circuit Breaker Switchgear, IEEE Std C37.20.2™, Standard for Metal-Clad Switchgear, and IEEE Std C37.20.3™, Standard for Metal-Enclosed Interrupter Switchgear. By definition, metal-enclosed power switchgear assemblies include metal-clad switchgear, metal-enclosed interrupter switchgear, and low-voltage power circuit breaker switchgear. Metal-enclosed bus or control switchboards are not covered in this guide.