Double-wall and Single-wall Comparison
Electromagnetic shielding is an approach to avoid undesired electromagnetic energy being coupled into equipment under test. The ability of an enclosure to avoid undesired electromagnetic fields to couple to the device under test is known as its Shielding Effectiveness(SE). This term represents the ratio of field strength with and without the enclosure. SE for RF enclosures is always compromised by apertures, slots, cable penetration, etc.