MIL-STD-464C is the United States military standard that establishes the electromagnetic environmental effects requirements at system level, that is, for a complete platform such as an aircraft, a ship, a ground vehicle or a facility, rather than for the individual items of equipment installed in it. The distinction is fundamental: an equipment standard controls what a single unit emits and how susceptible it is, while the system standard controls the outcome of installing many such units together, with their cables routed as they will be in service and with their antennas operating, which is where the majority of serious problems arise. The standard therefore addresses the safety margins to be maintained between the emission of one subsystem and the susceptibility of another, the hazards from electromagnetic radiation to personnel, to fuel and to ordnance, and the effects of lightning, of the electromagnetic pulse of a nuclear detonation and of high intensity radiated fields on the platform as a whole, together with the analysis and test programme by which compliance is demonstrated.