The Short Answer
MIL-STD-461 controls electromagnetic interference (EMI) for electronic, electrical and electromechanical equipment used by the US military. It is the equipment-level EMC standard: it defines both how much interference a device may emit and how much external interference it must withstand without malfunctioning.
-
//
CE — Conducted Emissions Interference a device puts back onto its power and signal leads.
-
//
CS — Conducted Susceptibility Interference the device must tolerate arriving on those leads.
-
//
RE — Radiated Emissions Interference the device radiates into the surrounding space.
-
//
RS — Radiated Susceptibility Radiated interference the device must operate through.
Why It Matters
Military platforms are electromagnetically dense: radios, radar, motors and other computers share a confined space. A computer that meets MIL-STD-461 is less likely to disrupt, or be disrupted by, the systems around it. It is the equipment-level partner to the system-level MIL-STD-464.
See our overview of U.S. military standards (MIL-STDs) for how this fits alongside the others.