https://palomar-engineers.com and a portable TinySA spectrum analyzer (Amazon $60) will help you find emission sources, identify their frequency, and kill them. You must choose the right ferrite material for the frequency. Many meters don't even measure in the range of a lot of common emissions.
If magnetic fields are a concern, use efficient devices that move less current through wires, and never coil them.
Ham radio operators, other than intentionally blasting ourselves with RF, tend to have very low EMI around the house. I'm not an RF engineer, but I am an accomplished EMI-killer.