This standard specifies in detail the method for determining the impact toughness of fiber-reinforced plastics using a simply supported beam pendulum impact testing machine. By placing a specimen with a V-shaped notch on supports with a specific span, the pendulum delivers a single impact to cause stress concentration and failure at the notch, thereby accurately evaluating the material's impact resistance. The test results hold significant reference value for the research and development of composite materials, quality control, and performance evaluation in applications where the products may be subjected to impact loads. In practical testing, simply supported beam pendulum impact testing machines for non-metallic materials are typically used. Such equipment must comply with the strict requirements in the standard regarding key dimensions, such as pendulum energy, support span (70 mm), and impact blade dimensions. Many modern models also feature high-precision measurement and automatic data processing functions to ensure the accuracy and repeatability of test results.