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Radiographic Testing Technician
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A Instant Download Pdf
___________________________________________________________________
1. What is the primary purpose of radiographic testing (RT) in nondestructive
examination?
A. To measure surface roughness
B. To detect and evaluate internal discontinuities
C. To determine electrical conductivity
D. To measure hardness
Answer: To detect and evaluate internal discontinuities
Rationale: Radiographic testing uses penetrating radiation to produce an image
of an object's internal structure, allowing discontinuities such as porosity,
inclusions, cracks, and lack of fusion to be evaluated.
2. Which type of radiation is most commonly used for industrial radiography?
A. Ultraviolet radiation
B. Infrared radiation
C. X-rays and gamma rays
D. Microwave radiation
Answer: X-rays and gamma rays
Rationale: Industrial radiography primarily uses X-rays generated electrically
and gamma rays emitted by radioactive isotopes.
, 3. Which property of X-rays makes them useful for radiographic testing?
A. They cannot penetrate metals
B. They have high penetrating power
C. They are visible to the human eye
D. They only travel through liquids
Answer: They have high penetrating power
Rationale: X-rays have sufficient energy to penetrate materials, with different
amounts of radiation being absorbed according to material thickness and
density.
4. What is the SI unit of absorbed radiation dose?
A. Sievert
B. Gray
C. Becquerel
D. Coulomb
Answer: Gray
Rationale: The gray (Gy) is the SI unit of absorbed dose and represents one joule
of radiation energy absorbed per kilogram of material.
5. What is the SI unit used for equivalent or effective dose?
A. Gray
B. Becquerel
C. Sievert
D. Curie
Answer: Sievert
Rationale: The sievert (Sv) accounts for the biological effect of radiation and is
used for equivalent and effective dose.
6. What is the unit of radioactive activity in the SI system?
,A. Gray
B. Sievert
C. Becquerel
D. Roentgen
Answer: Becquerel
Rationale: The becquerel (Bq) represents one radioactive disintegration per
second.
7. Which radiation source is commonly used in gamma radiography of thick
steel?
A. Iridium-192
B. Hydrogen-1
C. Carbon-12
D. Oxygen-16
Answer: Iridium-192
Rationale: Iridium-192 is widely used for industrial gamma radiography and is
particularly useful for many steel and weld applications.
8. Which isotope is commonly used when greater penetration than Iridium-
192 is required?
A. Cobalt-60
B. Carbon-14
C. Tritium
D. Cesium-137 only
Answer: Cobalt-60
Rationale: Cobalt-60 emits higher-energy gamma radiation than Iridium-192
and is therefore suitable for thicker or denser materials.
9. What happens to radiation intensity as the distance from a point source
increases?
, A. It increases linearly
B. It remains constant
C. It decreases according to the inverse square law
D. It becomes independent of distance
Answer: It decreases according to the inverse square law
Rationale: Radiation intensity from a point source is inversely proportional to
the square of the distance from the source.
10.If the distance from a radiation source is doubled, the radiation intensity
becomes approximately:
A. Four times greater
B. Twice as great
C. One-half as great
D. One-quarter as great
Answer: One-quarter as great
Rationale: Under the inverse square law, doubling the distance reduces intensity
to 1/(2²), or one-quarter of its original value.
11.Which three basic principles provide the foundation for radiation
protection?
A. Heat, pressure, and shielding
B. Time, distance, and shielding
C. Speed, temperature, and density
D. Frequency, wavelength, and velocity
Answer: Time, distance, and shielding
Rationale: Radiation exposure is reduced by minimizing time near the source,
maximizing distance, and using appropriate shielding.
12.What is the main purpose of a radiation survey meter?
Radiographic Testing Technician
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A Instant Download Pdf
___________________________________________________________________
1. What is the primary purpose of radiographic testing (RT) in nondestructive
examination?
A. To measure surface roughness
B. To detect and evaluate internal discontinuities
C. To determine electrical conductivity
D. To measure hardness
Answer: To detect and evaluate internal discontinuities
Rationale: Radiographic testing uses penetrating radiation to produce an image
of an object's internal structure, allowing discontinuities such as porosity,
inclusions, cracks, and lack of fusion to be evaluated.
2. Which type of radiation is most commonly used for industrial radiography?
A. Ultraviolet radiation
B. Infrared radiation
C. X-rays and gamma rays
D. Microwave radiation
Answer: X-rays and gamma rays
Rationale: Industrial radiography primarily uses X-rays generated electrically
and gamma rays emitted by radioactive isotopes.
, 3. Which property of X-rays makes them useful for radiographic testing?
A. They cannot penetrate metals
B. They have high penetrating power
C. They are visible to the human eye
D. They only travel through liquids
Answer: They have high penetrating power
Rationale: X-rays have sufficient energy to penetrate materials, with different
amounts of radiation being absorbed according to material thickness and
density.
4. What is the SI unit of absorbed radiation dose?
A. Sievert
B. Gray
C. Becquerel
D. Coulomb
Answer: Gray
Rationale: The gray (Gy) is the SI unit of absorbed dose and represents one joule
of radiation energy absorbed per kilogram of material.
5. What is the SI unit used for equivalent or effective dose?
A. Gray
B. Becquerel
C. Sievert
D. Curie
Answer: Sievert
Rationale: The sievert (Sv) accounts for the biological effect of radiation and is
used for equivalent and effective dose.
6. What is the unit of radioactive activity in the SI system?
,A. Gray
B. Sievert
C. Becquerel
D. Roentgen
Answer: Becquerel
Rationale: The becquerel (Bq) represents one radioactive disintegration per
second.
7. Which radiation source is commonly used in gamma radiography of thick
steel?
A. Iridium-192
B. Hydrogen-1
C. Carbon-12
D. Oxygen-16
Answer: Iridium-192
Rationale: Iridium-192 is widely used for industrial gamma radiography and is
particularly useful for many steel and weld applications.
8. Which isotope is commonly used when greater penetration than Iridium-
192 is required?
A. Cobalt-60
B. Carbon-14
C. Tritium
D. Cesium-137 only
Answer: Cobalt-60
Rationale: Cobalt-60 emits higher-energy gamma radiation than Iridium-192
and is therefore suitable for thicker or denser materials.
9. What happens to radiation intensity as the distance from a point source
increases?
, A. It increases linearly
B. It remains constant
C. It decreases according to the inverse square law
D. It becomes independent of distance
Answer: It decreases according to the inverse square law
Rationale: Radiation intensity from a point source is inversely proportional to
the square of the distance from the source.
10.If the distance from a radiation source is doubled, the radiation intensity
becomes approximately:
A. Four times greater
B. Twice as great
C. One-half as great
D. One-quarter as great
Answer: One-quarter as great
Rationale: Under the inverse square law, doubling the distance reduces intensity
to 1/(2²), or one-quarter of its original value.
11.Which three basic principles provide the foundation for radiation
protection?
A. Heat, pressure, and shielding
B. Time, distance, and shielding
C. Speed, temperature, and density
D. Frequency, wavelength, and velocity
Answer: Time, distance, and shielding
Rationale: Radiation exposure is reduced by minimizing time near the source,
maximizing distance, and using appropriate shielding.
12.What is the main purpose of a radiation survey meter?
