This standard specifies in detail the Thermal Reliability Test Method for Phase Change Materials for Buildings, including principles, instrumentation, test procedures, data processing and reporting. It is suitable for thermal Reliability testing of solid-liquid phase change materials used in buildings, and the performance of phase change materials can be evaluated by accelerated hot and cold cycling tests and differential scanning calorimetry. The Terms and Definitions section provides detailed definitions of phase change materials and related performance, including phase change temperature, latent heat of phase change, etc.