This Technical Report 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. 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.