What color glow indicates an indication when using fluorescent penetrant methods?

When utilizing fluorescent penetrant methods in liquid penetrant testing, the indication of defects is indicated by a brilliant yellow-green glow. This specific color reaction occurs when the penetrant, which has been absorbed into the surface cracks or defects, is exposed to ultraviolet (UV) light. The brilliant yellow-green fluorescence stands out distinctly against a deep violet-blue background, making it easier for inspectors to identify and evaluate discontinuities in the material being inspected.

The contrast between the yellow-green glow and the deep violet-blue background is critical in ensuring that any indications are readily visible. This high-contrast scenario is essential for effective inspection since it highlights flaws in materials that may not be easily detected under normal lighting conditions. The chemical properties of the fluorescent penetrant, combined with the specific lighting conditions used during testing, are designed to enhance visibility and allow for accurate assessments of the integrity of the tested materials.