GB/T 18830-2009 "Spinning & weaving products, evaluation of UV protection performance" standard specifies the method and standard for evaluating the performance of Spinning & weaving products to protect against sunlight ultraviolet rays. This standard covers the definition of terms, test principles, evaluation methods and labeling requirements. The UV protection coefficient UPF value of the sample can be calculated by using UV radiation samples and measuring the total Light spectrum transmission rays. Only when the UPF value is greater than 40 and the UVA transmittance is less than 5%, the product can be called "UV protection product". The standard requires product labels to indicate the national standard number GB/T 18830-2009 and the UPF value, such as 40 + or 50 +, depending on the range of UPF values. The nature of this standard recommendation allows manufacturers to choose whether to produce UV protection products according to actual needs, but if they want to label "UV protection products", they must comply with the provisions of this standard.