This part of IEC 61000 covers guidelines for the mitigation of external electromagnetic influences impinging upon a facility, aimed at ensuring electromagnetic compatibility (EMC) among electrical and electronic apparatus or systems. These influences include lightning, RF transmitters, power-line and telecom transients, high-altitude electromagnetic pulse (HEMP) and other high-power electromagnetic transients. More particularly, this technical report is concerned with the arrangement of shielding and screening against radiated disturbances, and with mitigation of conducted disturbances. These arrangements include appropriate electromagnetic barriers for industrial, commercial, and residential installations.

The concept of barriers installed for mitigating potentially penetrating and unwanted electromagnetic noise is applicable even when there is no designed-in electromagnetic shield. The enclosure through which power and signal (communications, control, etc.) cables must enter or exit may be considered as a potential electromagnetic barrier that will provide some level of protection. The concept of enclosure can be understood as the perimeter walls of a building, the walls of a single room, or the housing of an apparatus, with protection installed at all points of electromagnetic penetration into the enclosure.

This technical report is intended for use by installers, manufacturers and users of sensitive electrical or electronic installations or systems, and of equipment with emission levels that could degrade the overall electromagnetic (EM) environment. It applies primarily to new installations but, where economically feasible, it may be applied to extensions or modifications to existing facilities. While the technical principles are applicable to individual equipment or apparatus, such application is not included in the scope of this technical report.