GJB 548B is the Chinese national military standard that contains the test methods and procedures for microelectronic devices used in military equipment. It corresponds in scope to the United States military standard for microcircuits and, like it, provides a catalogue of numbered methods that a procurement programme selects according to the requirement it wishes to verify. The methods cover the electrical tests that establish the parametric and functional performance of a device, the environmental tests that demonstrate its resistance to temperature cycling, thermal shock, moisture and mechanical stress, the life tests that establish its reliability, and the tests that characterise its sensitivity to electrostatic discharge and to the electrical overstress that occurs during handling and assembly. Each method states the apparatus, the sample size, the conditions, the procedure and the acceptance criteria in a form that makes the result reproducible between laboratories.