Each equipment design shall provide electrical continuity across mechanical interfaces in accordance with the design requirements of this specification. Electrical continuity will be achieved to the maximum practical extent by direct metal-to-metal contact across the entire interface surface. If the electrical resistance across mechanical interfaces is measured to be less than 1 ohm, then electrical continuity will be considered to be achieved. The following guidelines are best practices for achieving electrical continuity:
- Where protective finishes are necessary to prevent oxidation or corrosion, an electrically conductive surface treatment must be employed. For example, aluminum surfaces should be treated with a chemical film in accordance with MIL-C-5541B, Class 3.
- When dissimilar metals are involved, the interface must be designed in accordance with MIL-STD-889B.
- Mating surfaces should be free of nonconductive contaminants including paint, machining oils and milling inks.
"DISSIMILAR METALS". MIL-STD-889B, DoD, WPAFB, Ohio, 1976, DISSIMILAR METALS.