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

When should the inspection of a test specimen for discontinuities take place during penetrant testing?

1. Immediately after applying the penetrant

2. After the developer has been on the test specimen for the proper development time

3. Before applying the penetrant

4. During the emulsification step

The correct answer is: After the developer has been on the test specimen for the proper development time

The inspection of a test specimen for discontinuities should take place after the developer has been on the test specimen for the proper development time. This timing is crucial because the developer acts to draw out the penetrant that has infiltrated any discontinuities in the surface of the specimen. By allowing the developer to remain in contact with the test specimen for the appropriate amount of time, it ensures that any visible indications of discontinuities are properly formed. This developed indication is what the inspector relies upon to identify issues such as cracks, voids, and other defects. If the inspection were to occur immediately after applying the penetrant, there wouldn't be any developed indications to analyze, as the penetrant would still be in the process of being absorbed into the defects. Inspecting before applying the penetrant would not be feasible, as there would be no penetrant in discontinuities to reveal. Similarly, inspecting during the emulsification step would not provide useful information, as this phase is about removing excess penetrant, rather than displaying any defect indications. In summary, conducting inspection after the proper development time allows for the effective visualization of any discontinuities that may be present, making it essential for accurate results in penetrant testing.