EMC and Functional Safety - Challenges and Standards

Safety functions are more and more carried out by electrical, electronic or programmable electronic systems. Such systems are exposed to electromagnetic phenomena like they typically exist in installations and therefore they could potentially be affected. As a consequence a failure of the safety function could arise which might cause harm to people. An appropriate immunity against electromagnetic disturbances has to be achieved and therefore EMC and safety requirements have to be merged. This paper describes an approach how to assess EMC of complex safety-related systems and how to establish proper function of such safety functions when being exposed to electromagnetic disturbances. Particular immunity levels are suggested to be introduced in combination with a special performance criterion "Functional Safety". Furthermore the situation regarding international standards dealing with both the areas, EMC and Functional Safety, respectively, is described.