Analisi, progettazione e verifica sperimentale di schermi passivi per la mitigazione dei campi magnetici in prossimità di impianti di riscaldamento ad induzione

European Directive 2004/40/EC makes necessary for employers to protect workers against the risks associated with EMF. The so called ACTION VALUES are specified for measurement purposes along with recommendations concerning risk management, health surveillance, information and training for those working in exposed conditions. The aim of this work is to explore critically in deep the assessment of exposition levels, the field intensity measurement, the design and verification of shields made by electrically conductive material applied on industrial systems for melting of metals with induction heating. The experience lead to the definition of some useful criterions to follow for improving the obtainable results in similar activities, particularly during field intensity measurements and shielding effectiveness computation, and pointed out the need for more efficient computation tools. An alternative approach, suitable for calculation of magnetic field intensity reduction by usage of passive shields, has been developed on purpose and tested against a commercial FEM software, showing promising features