Functional Safety Requires Much More than EMC Testing

Electronic and programmable electronic devices are increasingly being used to control appliances, equipment, vehicles and systems where errors or malfunctions in those devices can have functional safety implications. All such devices can suffer from electromagnetic interference (EMI). The functional safety of such equipment is covered by IEC 61508 [1] - but their EMI requirements are not (yet) correctly specified by any safety or electromagnetic compatibility (EMC) standards. This paper lists the shortcomings in existing EMI provisions, then introduces techniques for ensuring that EMI does not cause functional safety problems.