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IEC 61000-4-21: “Testing and measurement techniques–Reverberation chamber test methods”
IEC 61000-4-21 aims to standardize radiated testing (both emissions and immunity/susceptibility) in reverb chambers. This includes testing for shielding effectiveness.
MIL-STD-461: “Requirements for the Control of Electromagnetic Interference Characteristics of Subsystems and Equipment”
MIL-STD-461 is one of the core EMC standards, having evolved with military applications since WWII. It is widely used in the aerospace and defense sectors.