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

What is the most common type of contaminant in fluorescent penetrant fluid?

1. Oil

2. Water

3. Metal shavings

4. Dust particles

The correct answer is: Water

Fluorescent penetrant fluids are primarily used in liquid penetrant testing to detect surface-breaking defects in non-porous materials. Among the various contaminants that can affect the performance of these penetrants, water is particularly significant. Water can dilute the penetrant, which may reduce its effectiveness in locating defects. Additionally, the presence of water can also cause the penetrant to wash off the surface or interfere with the emulsification process needed before the developer is applied. Thus, water is viewed as the most prominent type of contaminant that can negatively impact the testing process by altering the fluid's properties, ultimately leading to inaccurate test results. Understanding the role of contaminants like water helps technicians ensure proper application and interpretation of the penetrant testing results, preserving the integrity of inspections.