GB/T 40359-2021 applies to photoluminescent coatings on time-measuring instrument components and test samples, specifying the test methods and relevant requirements. The standard covers test items such as color inspection, luminescent intensity, luminance, aging resistance, and resistance to high and low temperatures. It defines sample preparation, environmental conditions, and evaluation criteria for results. The testing requires the use of instruments such as photometers and fluorescence spectrometers, along with D65 standard light sources and high/low-temperature test equipment. Under specified temperature and humidity conditions, the coating's luminescent performance, stability, and appearance are evaluated through steps such as irradiation, dark storage, and measurement. This provides a technical basis for quality control of photoluminescent coatings in time-measuring instruments.