GB/T 39548-2020 "Determination of Thermal Resistance Retention of Vacuum Hot Plate under Heat and Humidity Conditions" specifies the method for determining the thermal resistance retention of Vacuum Hot Plate under specific temperature and Humidity conditions. This standard is used to evaluate the durability of Vacuum Hot Plate in long-term use and is applicable to the performance testing of related thermal insulation materials. The standard includes the instrumentation required for the test, sample requirements and measurement methods to ensure that the thermal resistance performance of Vacuum Hot Plate is accurately evaluated in heat and humidity environments. Special emphasis is placed on Humidity control and the use of heat flow meters to ensure the Reliability of test data.