This standard specifies a specialized test method for evaluating the resistance of hermetic semiconductor devices (i.e., hermetically sealed devices) to electrical breakdown under low-pressure environments. Its core purpose is to determine the ability of the device and its internal insulating materials to avoid high-voltage breakdown failure when air pressure decreases and the insulating strength of air weakens. This method is primarily applicable to high-voltage devices operating at voltages exceeding 1000 volts, and its typical application areas are explicitly defined as military and space fields. The test is typically conducted in a specialized low-pressure (or simulated high-altitude low-pressure) test chamber (also known as a sealed chamber). During operation, the device is placed inside the chamber, and the air pressure is reduced to a specified value (simulating a specific altitude) using a vacuum pump. Under these conditions, a high voltage is applied to the device. Simultaneously, instruments such as microammeters or oscilloscopes are used to monitor whether breakdown or abnormal leakage currents occur, thereby determining its reliability. This test serves as a critical basis for assessing the operational safety of semiconductor devices in extreme high-altitude environments such as aviation and aerospace.