NDT Cheat Sheet 2026

The 30 highest-yield NDT facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. When a procedure or code change occurs, what action regarding NDT personnel certification is typically required? → Personnel may need supplemental training and demonstration of continued qualification
2. Which type of sensor is most commonly used in acoustic emission testing? → Piezoelectric transducer
3. The term for the combined impact of absorption and dispersion is: → Attenuation
4. What is the primary advantage of using a hydrophilic emulsifier (Method D) over a lipophilic emulsifier (Method B)? → Greater process control and reduced risk of over-emulsification
5. Which penetrant testing method uses Method C classification? → Solvent-removable penetrant
6. What is the critical angle in angle-beam ultrasonic testing? → The incident angle at which the refracted wave travels along the interface at 90°
7. In visual testing, 'transillumination' technique involves: → Passing light through a translucent material to reveal internal variations
8. What is the primary advantage of multidirectional magnetization in magnetic particle testing? → Detection of discontinuities in multiple orientations in one operation
9. Which code governs NDT personnel qualification for nuclear power plant in-service inspections in the US? → ASME Section XI
10. Which type of ultrasonic wave motion involves particles oscillating perpendicular to the direction of wave propagation? → Shear (transverse) wave
11. What is the key distinguishing characteristic of fluorescent magnetic particles compared to visible (dry) particles? → They fluoresce under ultraviolet light, providing higher contrast
12. Iridium-192 cameras used in field radiography must be surveyed for radiation levels and integrity after each use. This is required under: → NRC regulations under 10 CFR Part 34
13. Which type of wave travels along the surface of a material and is useful for detecting shallow surface-breaking flaws? → Surface (Rayleigh) wave
14. A surface-breaking crack detected by PT is evaluated and found to be relevant. The next required step per most codes is: → Assess against the applicable acceptance criteria
15. According to ASME codes, when recording UT indications for welds, an indication is typically recordable if its amplitude exceeds what threshold? → 50% of the DAC curve
16. In NDT certification, what does 'recertification' typically require? → Proof of continuing education and/or reexamination per the Written Practice
17. A visual inspector notices a crack that appears to run parallel to the direction of the applied stress on a pressure vessel. This orientation is: → Less critical than a transverse crack in most cases
18. A 'lost or stolen' radioactive source must be reported to the NRC within: → 4 hours of discovery
19. In full matrix capture (FMC) phased array UT, what data is collected compared to conventional PAUT? → The complete A-scan from every transmitter-receiver element combination
20. Increasing the temperature will: → Raise the speed of evaporation of penetrants
21. Demagnetization of a component after magnetic particle testing is crucial in which of the following scenarios? → When the part is a moving component in an assembly, like a bearing.
22. Which ASME code section specifically governs inspection of in-service pressure vessels? → API 510
23. Which of the following material properties has the MOST significant influence on the magnitude and distribution of induced eddy currents? → Electrical Conductivity
24. Which isotope has the longest half-life among those commonly used in industrial radiography? → Cobalt-60 (Co-60)
25. According to ASME Section V Article 4, what is the maximum film density allowed for radiographic examination of welds in steel? → 2.0 to 4.0 H&D
26. What distinguishes an NDT 'technique' from an NDT 'method'? → A technique is a specific application or variation within a method
27. For water soluble developer, which kind of developer is used? → Form b
28. During liquid penetrant inspection, a rounded indication with a diameter approximately equal to its length is classified as: → Rounded
29. Which pulse duration characteristic has the greatest impact on ultrasonic axial (depth) resolution? → Pulse duration (wavelength count in the pulse)
30. Other names for longitudinal waves are: → Both Pressure waves and Compressional waves are correct