MIL-STD-461 is a United States Military Standard that describes how to test equipment for electromagnetic compatibility.
Various revisions of MIL-STD-461 have been released. Many military contracts require compliance to MIL-STD-461E. The latest revision (as of 2015) is known as "MIL-STD-461G".
While MIL-STD-461 compliance is technically not required outside the US military, many civilian organizations also use this document.
Electromagnetic compatibility test labs typically set up their anechoic chamber to comply with MIL-STD-461. Test labs attempt to comply with this standard for two reasons :
- Even if no potential customer requires MIL-STD-461 compliance, if a device complies with (or is very close to complying to) the (relatively strict) MIL-STD-461, then it is certain to comply with the (relatively looser) FCC Part 15 and EMC standards of other countries, and it is simpler to run one test than to run a separate test for each one.
- Even if only a few of the potential customers require MIL-STD-461, it's simpler to design a single commercial off-the-shelf product that complies with the most strict standard—MIL-STD-461—rather than trying to track several versions of a product that each comply with separate standard.
In 1999, MIL-STD-462 was combined with MIL-STD-461D into MIL-STD-461E.