Which is a factor that can affect the results of liquid penetrant testing?

Liquid penetrant testing is a non-destructive testing method used to detect surface defects in materials, primarily metals. One of the critical factors that can significantly influence the outcomes of this testing method is the condition of the surfaces being examined.

Contaminated surfaces introduce substances such as oils, grease, paint, or dirt that can hinder the penetrant from properly adhering to or entering the defects. This contamination can create misleading results, potentially masking flaws that would otherwise be detected. For the test to be effective, the surfaces must be clean, dry, and free from any contaminants that may affect the penetrant's ability to reveal cracks or other imperfections.

Maintaining a clean environment before testing is essential, as it maximizes the chances of accurately detecting defects and ensures the reliability of the test results. Factors such as illumination quality, material thickness, and surface color may have roles in the testing process, but they are more secondary to the necessity of a clean testing surface.