Non-Destructive Testing (NDT) Practice Test

When preparing for penetrant inspection, what is a critical step that should not be overlooked?

1. Choosing the color of the penetrant

2. Cleaning the surface properly

3. Determining inspection angles

4. Ensuring part temperature compliance

The correct answer is: Cleaning the surface properly

Cleaning the surface properly is a critical step in the penetrant inspection process because it directly impacts the effectiveness and reliability of the inspection results. Penetrant testing relies on the ability of the liquid penetrant to seep into surface-breaking defects. If the surface is contaminated with dirt, grease, oil, or any other substances, these contaminants can impede the penetrant's ability to enter defects. Effective cleaning ensures that the surface is free from any materials that could obstruct the penetrant. This step is essential not only for obtaining accurate test results but also for ensuring that any flaws or discontinuities present are properly identified. While other aspects like choosing the color of the penetrant, determining inspection angles, and ensuring part temperature compliance are important, they all depend on a clean surface to function effectively. Without proper cleaning, even the best chosen penetrant or the most ideal inspection angle would not yield accurate assessments of the component's integrity.