Because the meter housing is plastic, the electric fields can penetrate through to the plates, which are also arranged to detect AC electric fields in the X, Y, and Z directions. Circuitry similar to the magnetic section converts the signals into an electric field signal which is frequency-weighted. This is because the electric field component of radio waves produces much weaker currents in the body than does the magnetic field unless the wavelength of the waves is smaller than the height of the body. Low-frequency electric fields by themselves can be strong enough to create significant current, but only if they are from sources other than true radio waves. As mentioned, a true radio wave is a particular combination of electric and magnetic fields.
Typical accuracy is within a factor of two.
Variations are caused by reflections off the user's hand and body.