It’s incumbent on electrical/electronic designers and troubleshooters to understand the difference between electromagnetic interference (EMI) and electromagnetic compatibility (EMC).
EMI is caused by electromagnetic emissions that may disturb the function of electronic devices and radio-frequency (RF) systems. Such devices and systems must be properly shielded from electromagnetic radiation for them to perform optimally. EMC measures how well these devices and systems can perform in the presence of any disruptive EMI.