Some people are concerned about "electromagnetic smog" and install meshes on their windows to absorb electromagnetic waves. A particular product advertises "50-dB attenuation in the range from \(10 \mathrm{MHz}\) to \(3 \mathrm{GHz}\)," with attenuation defined as

\[\text { attenuation }(\mathrm{dB})=10 \log \left(\frac{\text { input intensity }}{\text { output intensity }}\right) \text {. }\]

The meshes (sometimes called Faraday cages or Faraday meshes) generally work if the diameter of the holes is smaller than the wavelength of the radiation. You naturally wonder what this means in terms of reductions in the wave intensity and field strengths. However, it is also curious that the manufacturer advertises a frequency range, so you begin to think about the maximum mesh diameter allowed and whether a minimum is required.