What is the definition of a discontinuity?

A discontinuity in visual testing refers to any interruption or break in the physical structure of a material. It does not inherently indicate that the material is defective or that it must be rejected.

Discontinuities can include a range of issues, such as cracks, voids, or inclusions, but they might not always affect the overall integrity or performance of the material. For example, some discontinuities might fall within acceptable limits defined by industry standards, meaning that they do not necessitate rejection of the material or component.

Therefore, stating that a discontinuity is always a defect or always rejectable does not capture the nuanced decision-making that goes into evaluating whether a discontinuity affects the material's usability or safety. Each discontinuity must be assessed on a case-by-case basis, considering the specific context and acceptance criteria relevant to the material or application at hand.