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MIL-STD-464: “Electromagnetic Environmental Effects Requirements for Systems”
MIL-STD-464 is the main aerospace/defense document that applies E3 requirements to full systems and platforms.
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.