This standard serves as a fundamental test method for evaluating the aging resistance of plastic materials under long-term thermal environments. Its core procedure involves exposing plastic specimens to a thermal aging test chamber (commonly known as an oven or aging chamber) set at a specific temperature. After a specified duration, the specimens are removed, and the changes in their key properties (such as tensile strength, elongation at break, impact strength, color change, etc.) before and after aging are measured. This process is used to assess the material's thermal stability and estimate its service life. The standard specifies detailed requirements for the temperature uniformity of the test chamber, the placement of specimens, and conditioning conditions to ensure the comparability of test results. This method is widely applied in quality control, material screening, and lifespan prediction for plastic products.