What is a possible consequence of excessive emulsification time in penetrant testing?

In penetrant testing, emulsification refers to the process of mixing the penetrant with an emulsifier to remove excess surface penetrant before a developer is applied. If emulsification time is excessive, the penetrant can be overly diluted or washed away, leading to a reduction in sensitivity of the indications.

When the emulsification is prolonged beyond the optimal time, shallow discontinuities—such as small cracks or voids—may not retain enough penetrant to create a visible indication during the subsequent development phase. This can result in lost detection of critical defects that might be present on the surface, which is a significant concern in non-destructive testing where the goal is to identify flaws that could affect the integrity of the material or component being inspected. Thus, shallow discontinuity indications could indeed be lost as a consequence of excessive emulsification time.

In contrast, while the other options provide different scenarios, they do not address the direct impact of prolonged emulsification on the visibility of indications specifically related to shallow discontinuities in penetrant testing.