Performance assessment of EMC coatings

The interest about the Electro-Magnetic Compatibility (EMC) and electro-mag netic environmental pollution in the last years is reflected in the worldwi de standardization process. In particular, the European 89/336/EEC Directiv e and the related technical standards have forced producers of electric and electronic devices to find out new solutions in order to reduce the electr omagnetic emissions and susceptibility. To the purpose the equipment has to be protected by an external shield, whi ch in cases where equipment housings are made in non-conductive polymeric m aterials can be provided by a proper conductive coating. In the paper a detailed test procedure to evaluate the fundamental paramete rs of conductive coatings with electromagnetic shielding properties is prop osed. In particular new test methods and experimental results that involve the use of an anechoic chamber and other instrumentation suitable to define the electric, magnetic and screening effectiveness characteristics of EMC shielding coatings and their active components are described.