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

When using fluorescent water washable penetrant, how can adequate rinsing of the part be assured?

1. Rinsing under cold water

2. Rinsing under blacklight

3. Using a high-pressure washer

4. Rinsing in a solvent bath

The correct answer is: Rinsing under blacklight

When using fluorescent water-washable penetrant, rinsing under blacklight allows the technician to visually assess the adequacy of the rinsing process. This is important because proper rinsing is crucial to ensure that excess penetrant is removed, which helps in achieving clear indications of defects without interference. Under blacklight, any remaining penetrant will fluoresce and be visible, making it easy to determine if the part has been adequately cleaned. This technique helps to ensure that when the penetrant inspection process continues, the indications seen correspond to true defects in the material rather than being artifacts of leftover penetrant. Rinsing under cold water or with a high-pressure washer may not provide the same level of visual confirmation of cleaning effectiveness, as these methods do not allow for real-time verification of residual penetrant. Rinsing in solvent is not suitable for water-washable penetrants and may compromise the integrity of the part. Therefore, using blacklight is an effective strategy to ensure thorough rinsing is achieved.