GB4599 standard uses silica sand

The GB4599-2024 standard for automotive road lighting devices and systems specifiesGB4599 standard uses silica sandThe requirements are as follows:

The experimental mixture ratio is 25 g of silica sand per liter of water, consisting of silica sand with a Mohs hardness of 7, particle size of 0 mm~0.2 mm, normal distribution, and angular factor of 1.8~2; Hard water not exceeding 205 g/square meter.

The outer surface of the light distribution mirror in Experiment K.2.1 should withstand the action of one or more test mixtures, and the mixture should be sprayed vertically onto the surface of the sample. K. 2.2 Place one or several flat glass specimens with a thickness of 2 mm near the test lens as a reference to check the wear condition and the uniformity of the wear on the entire surface of the specimen. K. 2.3 The spray test of the mixed solution shall be terminated when the change rate of the diffuse transmittance of the reference glass sample measured according to the method specified in Appendix J is 0.025 0 ± 0.002 5, and calculated according to formula (K.l): where: the change rate of the diffuse transmittance of the bundle d; 6. d=- T s - T4 Transmission light reading of Wu Xin material in a 24 ° field of view; Diffuse light reading of Wuxin materials; The diffuse light reading of the material after the experiment.