The ISO 18473-2:2015 standard specifies requirements and test methods for nano-scale titanium dioxide for sunscreen applications. Nano-scale titanium dioxide is widely used in sunscreen products to provide effective skin protection due to its excellent UV absorption and scattering performance. Compared with traditional pigments, nano-scale titanium dioxide can significantly improve UV protection due to its smaller particle size. The purpose of this standard is to clarify the performance requirements of nano-scale titanium dioxide in sunscreen products, standardize its testing methods, and ensure the conformity and Reliability of the product, thereby promoting the application and technical exchange of this type of material in the market.