ASNT LEVEL III NONDESTRUCTIVE TESTING CERTIFICATION PRACTICE
EXAMINATION NEWEST (2026 UPDATE) FROM REAL PAST PAPERS
QUESTIONS – SET 100 MOST COMMON EXAM FREQUENTLY TESTED
QUESTIONS AND ANSWERS IN DETAILS 100% VERIFIED EXAM HIGHLY
RECOMMENDABLE FOR GRADE A+
1. Which NDT method is most suitable for detecting surface-breaking cracks in
ferromagnetic materials
A. Radiographic Testing
B. Ultrasonic Testing
C. Magnetic Particle Testing
D. Eddy Current Testing
✔ Correct Answer: C. Magnetic Particle Testing
Magnetic Particle Testing is specifically effective for detecting surface and
near-surface discontinuities in ferromagnetic materials due to magnetic
flux leakage.
2. In Ultrasonic Testing, the term “attenuation” refers to
A. Increase in signal amplitude
B. Loss of sound energy during propagation
C. Reflection of waves at boundaries
D. Frequency increase in material
✔ Correct Answer: B. Loss of sound energy during propagation
Attenuation describes the reduction in ultrasonic wave amplitude as it
travels through a material due to scattering and absorption.
3. Which radiographic source provides the highest energy gamma rays
A. Iridium-192
B. Cobalt-60
C. Selenium-75
D. Cesium-137
✔ Correct Answer: B. Cobalt-60
, Cobalt-60 emits higher energy gamma radiation, making it suitable for
thicker materials inspection.
4. Eddy current testing is primarily limited to
A. Non-conductive materials
B. Ferromagnetic materials only
C. Electrically conductive materials
D. Transparent materials
✔ Correct Answer: C. Electrically conductive materials
Eddy currents are induced in conductive materials, making this method
applicable only to such materials.
5. Which liquid penetrant property is most critical for detecting fine cracks
A. Density
B. Viscosity
C. Surface tension
D. Color contrast
✔ Correct Answer: C. Surface tension
Low surface tension allows penetrant to enter fine discontinuities
effectively through capillary action.
6. In Radiographic Testing, film density refers to
A. Film thickness
B. Degree of darkness on film
C. Radiation energy
D. Exposure time
✔ Correct Answer: B. Degree of darkness on film
Film density is the measure of blackening on the radiographic film caused
by radiation exposure.
7. A discontinuity that interrupts the normal physical structure of a material is
called
A. Defect
B. Indication
, C. Discontinuity
D. Flaw
✔ Correct Answer: C. Discontinuity
A discontinuity is any interruption in material structure, not necessarily
rejectable.
8. Which UT wave type travels fastest in solids
A. Shear wave
B. Surface wave
C. Longitudinal wave
D. Plate wave
✔ Correct Answer: C. Longitudinal wave
Longitudinal waves have the highest velocity due to particle motion
parallel to propagation.
9. In Magnetic Particle Testing, dry particles are preferred when
A. Detecting subsurface defects
B. High sensitivity is required
C. Inspecting rough surfaces
D. Using fluorescent particles
✔ Correct Answer: C. Inspecting rough surfaces
Dry particles are better suited for rough surfaces where wet methods may
not perform well.
10.Which factor affects resolution in radiography
A. Source size
B. Film thickness
C. Material color
D. Temperature
✔ Correct Answer: A. Source size
Smaller source size improves geometric sharpness and radiographic
resolution.
EXAMINATION NEWEST (2026 UPDATE) FROM REAL PAST PAPERS
QUESTIONS – SET 100 MOST COMMON EXAM FREQUENTLY TESTED
QUESTIONS AND ANSWERS IN DETAILS 100% VERIFIED EXAM HIGHLY
RECOMMENDABLE FOR GRADE A+
1. Which NDT method is most suitable for detecting surface-breaking cracks in
ferromagnetic materials
A. Radiographic Testing
B. Ultrasonic Testing
C. Magnetic Particle Testing
D. Eddy Current Testing
✔ Correct Answer: C. Magnetic Particle Testing
Magnetic Particle Testing is specifically effective for detecting surface and
near-surface discontinuities in ferromagnetic materials due to magnetic
flux leakage.
2. In Ultrasonic Testing, the term “attenuation” refers to
A. Increase in signal amplitude
B. Loss of sound energy during propagation
C. Reflection of waves at boundaries
D. Frequency increase in material
✔ Correct Answer: B. Loss of sound energy during propagation
Attenuation describes the reduction in ultrasonic wave amplitude as it
travels through a material due to scattering and absorption.
3. Which radiographic source provides the highest energy gamma rays
A. Iridium-192
B. Cobalt-60
C. Selenium-75
D. Cesium-137
✔ Correct Answer: B. Cobalt-60
, Cobalt-60 emits higher energy gamma radiation, making it suitable for
thicker materials inspection.
4. Eddy current testing is primarily limited to
A. Non-conductive materials
B. Ferromagnetic materials only
C. Electrically conductive materials
D. Transparent materials
✔ Correct Answer: C. Electrically conductive materials
Eddy currents are induced in conductive materials, making this method
applicable only to such materials.
5. Which liquid penetrant property is most critical for detecting fine cracks
A. Density
B. Viscosity
C. Surface tension
D. Color contrast
✔ Correct Answer: C. Surface tension
Low surface tension allows penetrant to enter fine discontinuities
effectively through capillary action.
6. In Radiographic Testing, film density refers to
A. Film thickness
B. Degree of darkness on film
C. Radiation energy
D. Exposure time
✔ Correct Answer: B. Degree of darkness on film
Film density is the measure of blackening on the radiographic film caused
by radiation exposure.
7. A discontinuity that interrupts the normal physical structure of a material is
called
A. Defect
B. Indication
, C. Discontinuity
D. Flaw
✔ Correct Answer: C. Discontinuity
A discontinuity is any interruption in material structure, not necessarily
rejectable.
8. Which UT wave type travels fastest in solids
A. Shear wave
B. Surface wave
C. Longitudinal wave
D. Plate wave
✔ Correct Answer: C. Longitudinal wave
Longitudinal waves have the highest velocity due to particle motion
parallel to propagation.
9. In Magnetic Particle Testing, dry particles are preferred when
A. Detecting subsurface defects
B. High sensitivity is required
C. Inspecting rough surfaces
D. Using fluorescent particles
✔ Correct Answer: C. Inspecting rough surfaces
Dry particles are better suited for rough surfaces where wet methods may
not perform well.
10.Which factor affects resolution in radiography
A. Source size
B. Film thickness
C. Material color
D. Temperature
✔ Correct Answer: A. Source size
Smaller source size improves geometric sharpness and radiographic
resolution.
