EMC Question of the Week: March 31, 2025
Which acronym below was commonly used to describe electromagnetic interference decades ago?
- RMS
- ELF
- EMB
- RFI
Answer
The best answer is “d.” Long before the acronym EMI entered the lexicon, the term used to describe unwanted electromagnetic interference was RFI (Radio Frequency Interference). For the first hundred years after Hertz demonstrated the existence of electromagnetic radiation and Marconi demonstrated its practical application for wireless communications, most victims of electromagnetic interference were radio receivers. RFI was the term used to describe any form of electromagnetic interference including interference caused by transient sources such as arcing, ESD, or lightning.
In 1933, the International Electrotechnical Commission (IEC) established the International Special Committee on Radio Interference (CISPR) to address the problem of electromagnetic interference to radio communications. The IEEE EMC Society got its start in 1957 as the Institute of Radio Engineers Professional Group on Radio Frequency Interference. In 1963, when the IRE became part of the IEEE, the group was renamed the IEEE Professional Technical Group on Radio Frequency Interference. Later that year, it was rebranded as the IEEE Professional Technical Group on Electromagnetic Compatibility (now the IEEE EMC Society).
The name change was intended to recognize that this group was intended to address all forms of electromagnetic interference, not just interference at radio frequencies. There was a push to replace the use of the acronym RFI with the new acronym, EMI. Today, more than 60 years later, the acronym EMI has been widely adopted. However, we still see references to RFI in many of the older documents.
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