VDU emissions-what, why and standards

All electronic equipment has the potential to emit signals across a large part of the electromagnetic spectrum. The standards supporting the EMC Directive (and earlier national and industry requirements) concentrate on the higher frequency emissions in order to minimise the likelihood of interaction between electronic systems. This paper discusses the lower frequency emissions, some unique to visual display units (VDUs), which are not yet covered by formal standards. The emission levels discussed are very much lower than those required for reasons of compatibility with other systems and were generated pragmatically; they are not based on medical science