Specifies the test of empty cabinets and subracks concerning electromagnetic shielding performance, in the frequency range of 30 MHz to 1 000 MHz. Stipulated attenuation values are chosen for the definition of the shielding performance level of cabinets and subracks as per the IEC 60297 and IEC 60917 series. The purpose is to ensure physical integrity and environmental performance in cabinets and subracks.