ISO 9370-2017 "Instrumental Determination of Radiation Exposure in Plastic Aging Tests, General Guidance and Basic Test Methods" provides detailed guidance for radiation measuring instruments used in plastic aging tests. The standard covers instrumental techniques for the measurement of natural solar radiation, accelerated natural efflorescences, as well as laboratory Light source radiation. Particular emphasis is placed on the accurate selection and use of UV radiometers, including their calibrating procedures and their possible Light spectrum mismatch problems. The purpose of the standard is to ensure accurate measurement of radiation exposure under different test conditions to facilitate comparison between different experiments. This standard helps to improve Reliability and conformity in testing of plastic materials.