Liquid Penetrant Testing Level 1 (PT-1) Practice Exam

What effect does contamination of a water washable penetrant with excessive water have?

1. It enhances the penetration ability

2. It reduces the penetrating quality of the penetrant

3. It increases the drying time

4. It causes a color change

The correct answer is: It reduces the penetrating quality of the penetrant

Contamination of a water washable penetrant with excessive water reduces the penetrating quality of the penetrant because the addition of water dilutes the penetrant formulation. Penetrants are designed to have specific viscosities and surface tension properties that allow them to effectively infiltrate defects in the surface of the material being tested. When excessive water is introduced, it compromises these properties, making it more difficult for the penetrant to properly enter and fill the voids or cracks. This dilution can lead to a weaker signal when looking for indications of defects, therefore providing less reliable testing results. In contrast, other effects such as enhanced penetration ability, increased drying time, or a color change do not directly relate to the dilution of the penetrant with water. The primary concern with excessive water is its impact on the efficacy of the penetrant itself.