Non-Destructive Testing (NDT) Practice Test

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Prepare for the Non-Destructive Testing (NDT) Exam with our comprehensive practice tests. Utilize multiple choice questions, detailed explanations, and expert guidance. Achieve success and advance your career in NDT!

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During an NDT process, what is the purpose of using a black light?

To highlight flaws in the material.
To clean the surface area.
To evaluate the penetrant viscosity.
To saturate the material before inspection.

The correct answer is: To highlight flaws in the material.

The purpose of using a black light in Non-Destructive Testing (NDT), particularly in dye penetrant testing, is to highlight flaws in the material. When a fluorescent dye penetrant is applied to the surface of a part, it seeps into any surface break or flaw present. After a specified dwell time, excess penetrant is removed, and the part is inspected under a black light (ultraviolet light). The fluorescent properties of the dye cause it to emit light when exposed to the black light, making any discontinuities, such as cracks or voids, visibly stand out against the normal surface background. This enhanced visibility is crucial for ensuring that inspectors can accurately identify and assess flaws, which is central to maintaining the integrity and safety of various materials and structures. While other options may relate to different aspects of NDT processes, using a black light specifically serves the critical function of flaw detection, making it an essential tool in the overall evaluation procedure.