In a fluorescent penetrant test, a commonly used technique for assuring that the excess penetrant has been removed prior to the application of a developer is to

In a fluorescent penetrant test, a commonly used technique for assuring that the excess penetrant has been removed prior to the application of a developer is to

• A. Wipe with solvent
• B. Scan the surface with a black light
• C. Rinse with water and air dry
• D. Apply a UV light to cure

Answer: (B)

In fluorescent penetrant inspection, you verify that all excess penetrant has been removed by inspecting the surface under ultraviolet (black) light. After the cleaning step, you scan the area with UV light; any remaining penetrant will fluoresce. Seeing fluorescence indicates that additional cleaning is needed before applying the developer. This verification under UV ensures that the developer can work properly and that defects aren’t obscured by residual penetrant. Wipe with solvent or rinse with water are effective removal methods, but they don’t by themselves prove cleanliness unless you use UV light to confirm there’s no fluorescing residue. Applying a UV light to cure isn’t part of the process, since penetrant isn’t cured by UV in this test.

In fluorescent penetrant inspection, you verify that all excess penetrant has been removed by inspecting the surface under ultraviolet (black) light. After the cleaning step, you scan the area with UV light; any remaining penetrant will fluoresce. Seeing fluorescence indicates that additional cleaning is needed before applying the developer. This verification under UV ensures that the developer can work properly and that defects aren’t obscured by residual penetrant. Wipe with solvent or rinse with water are effective removal methods, but they don’t by themselves prove cleanliness unless you use UV light to confirm there’s no fluorescing residue. Applying a UV light to cure isn’t part of the process, since penetrant isn’t cured by UV in this test.