ISO 4630-1-2004 Transparent liquids for the assessment of Color by the Gardner scale Part 1: The visual method is an international standard that specifies the practice of assessing the Color of transparent liquids by visual method using the Gardner scale. The standard describes the steps for Color comparison using a standard Gardner color scale sample with a clear liquid sample to ensure that the assessor can determine the Color value by observing the degree to which the sample Color matches the standard Color scale under appropriate lighting conditions. The standard also specifies the requirements for the assessment environment, viewing angles and operating procedures to improve the accuracy and conformity of Color assessment. This method is widely used in beverage, chemical, cosmetics and other industries, especially for daily quality control and Color standardization management. Through the combination of visual method and Gardner color scale, it can provide a reliable Color mass evaluation basis for transparent liquid products.