This part of IEC 61587 specifies the tests for empty cabinets and subracks concerning electromagnetic shielding performance, in the frequency range of 30 MHz to 3 000 MHz. Stipulated attenuation values are chosen for the definition of the shielding performance level of cabinets and subracks for the IEC 60297 and IEC 60917 series. The shielding performance levels are chosen with respect to the requirements of the typical fields of industrial application. They will support the measures to achieve electromagnetic compatibility but cannot replace the final testing of compliance of the equipped enclosure. The purpose of this standard is to ensure physical integrity and environmental performance of cabinets and subracks, taking into account the need for different levels of performance in different applications. It is intended to give the user a level of confidence in the selection of products to meet his specific needs. This standard in whole or in part applies only to the empty enclosures, for example cabinets and subracks according to IEC 60297 and IEC 60917 and does not apply to the enclosures when electronic equipment is installed. Chassis may be tested in the same way as subracks and cases may be tested in the same way as cabinets. This standard was developed in close relationship to IEC 61000-5-7 but with the specific focus on subracks and cabinets and the determination of performance levels at the chosen frequency range.