The ISO 2931 standard specifies the technical requirements for the use of admittance methods to assess the sealing anodic oxide coatings mass during anodic oxidation of aluminum and its alloys. The standard evaluates the integrity and sealing effect of anodic oxide coatings by measuring the admittance value, so as to judge their anti-corrosion and weathering performance. Admittance method is a nondestructive detection method that can quickly and accurately detect the mass of anodic oxide coatings, especially the porosity and sealing properties of the film, ensuring that the coating has a good protective effect in practical applications. This standard is of great significance for the quality control, surface preparation process optimization and product performance verification of aluminum and its alloy products.