This is a test method used to evaluate the resistance of polymer material components used in electrical and electronic products to "abnormal heat." The principle involves applying a constant pressure of 20 N to the surface of the sample with a 5 mm diameter steel ball at a specified high temperature (e.g., 125°C for materials supporting live parts) for one hour. Subsequently, by measuring the diameter of the indentation formed on the sample surface, the material's resistance to softening under high-temperature loading conditions is assessed to evaluate its potential fire risk. This method is applicable to solid electrical insulating materials other than ceramics. The core testing instrument is commonly referred to as a ball pressure tester or abnormal heat resistance ball pressure tester. This device integrates a heating chamber with precise temperature control, a force application system, and a reading microscope for measuring indentations.