Which is an example of a condition that causes a false indication?

The example of a condition that causes a false indication is contamination on the surface. In various inspection methods, especially in non-destructive testing (NDT), any foreign substance on a test surface, such as oils, dirt, or other contaminants, can interfere with the inspection process. These contaminants may obscure defects or create artifacts that could be misinterpreted as flaws. As a result, the presence of contamination can lead to incorrect conclusions about the integrity of the material being inspected, leading inspectors to believe there is a defect when there is not, or missing actual defects that are present.

In comparison, excessive light during inspection may hinder visibility but does not necessarily create false indications of flaws. Dirt buildup from previous tests can also affect results but is more related to the clarity of observations rather than creating artificially false signals. Cold shut conditions refer to manufacturing defects in casting processes and are inherently recognized as real flaws, not false indications. Thus, contamination is the most direct cause of misleading results in inspection scenarios.