This International Standard specifies two low voltage tests for detecting and locating defects that extend to the basis metal in vitreous and porcelain enamel coatings.
Method A (electrical) is suitable for the rapid detection and determination of the general location of defects. Method B (optical), based on colour effects, is suitable for the more precise detection of defects and their exact locations. Method A is commonly applied to flat surfaces, whereas method B is preferred for more intricate shapes.
NOTE 1 Selection of the correct test method is critical to distinguish the areas of increased conductivity detected by method B from actual pores that extend to the basis metal, which can be detected by both methods.
NOTE 2 The low voltage test is a non-destructive method of detecting defects (see clause 3) and therefore, is completely differ-ent from the high voltage test specified in ISO 2746. The results of high and low voltage tests are not comparable and will differ.
BS EN ISO 8289:2001 history
2001BS EN ISO 8289:2001 Vitreous and porcelain enamels - Low voltage test for detecting and locating defects