This guide defines methods of measuring partial discharges that may occur in energized power switchgear apparatus in flaws, voids, and interfaces of nonself-restoring insulation that may then result in dielectric failure of the switchgear. Guidance on instrumentation and calibration technique is also given. The following types of equipment are included: high-voltage fuses, high-voltage switches, high-voltage circuit breakers, reclosers and sectionalizers, and switchgear assemblies.<>