This standard is a product specification developed for recycled plastic pellets produced from waste polystyrene (PS) and impact-resistant polystyrene (PS-I) plastics through physical recycling processes. It systematically specifies the classification, nomenclature, technical requirements, inspection methods, and evaluation rules for such recycled plastics. When assessing the performance of recycled polystyrene, the standard references commonly used plastic testing methods. These typically involve Fourier-transform infrared spectroscopy for material identification, melt flow rate testers for evaluating processing fluidity, and universal material testing machines for determining mechanical properties such as tensile strength. Together, these methods form a comprehensive quality control system.