The performance of a penetrant can be negatively affected by:

The performance of a penetrant can indeed be negatively impacted by surface contaminants. This is because liquid penetrant testing relies on the ability of the penetrant to seep into surface-breaking defects. If the surface is contaminated with oils, dirt, grease, rust, or other foreign substances, these contaminants can block the penetrant from accessing defects. Therefore, a clean surface is essential for the penetrant's effectiveness, as it allows for maximum adherence and penetration into flaws, ensuring accurate testing results.

Contaminated surfaces can also affect the reliability of the inspection results, leading to false negatives, where defects go undetected due to the penetrant being unable to penetrate or accurately display indications of a flaw. Proper surface preparation, therefore, is crucial before applying the penetrant in order to ensure optimal performance and accurate results during the inspection process.