MILSTD461

MIL-STD-461, titled "Requirements for the control of electromagnetic interference characteristics of subsystems and equipment," is a United States Department of Defense military standard governing electromagnetic compatibility (EMC) for electrical and electronic equipment intended for military use. The document specifies how equipment shall emit electromagnetic energy and how susceptible it must be to external electromagnetic environments, in order to prevent interference within platforms and with other systems.

Scope and content: The standard applies to devices and subsystems used in DoD programs and defines limits and test methods for both emissions and susceptibility across defined frequency ranges. Testing is performed at relevant stages of a program (design, integration, and acceptance) and the limits are selected from several environmental classes based on application, platform, and mission. The test methods are organized by category, commonly including conducted emissions, radiated emissions, conducted susceptibility, and radiated susceptibility. Each method specifies measurement setups, instrumentation, and acceptance criteria.

Compliance and usage: To meet MIL-STD-461, equipment designers employ techniques such as shielding, filtering, proper grounding, and careful cable routing, along with robust system integration practices. Vendors and contractors must document test results and demonstrate that the equipment remains within specified limits under worst-case conditions. The standard is periodically revised to reflect new technology and threats, and it remains a core reference in U.S. defense procurement and in allied programs that require DoD-compatible EMC performance.