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RADIATION SAFETY (AMMO 66)
FINAL COMPREHENSIVE EXAM ALL
QUESTIONS AND CORRECT
DETAILED ANSWERS |LATEST 2026-
2027 VERSION | ALREADY A GRADED
1. A radiologic technologist reduces fluoroscopy time during
a procedure primarily to adhere to which radiation safety
principle?
A. Dose limitation
B. ALARA
C. Justification
D. Optimization
Italicized rationale: ALARA (As Low As Reasonably
Achievable) emphasizes minimizing exposure time,
increasing distance, and using shielding to reduce
radiation dose.
2. Which type of radiation has mass and charge and is stopped
by a sheet of paper?
A. Alpha particles
B. Beta particles
C. Gamma rays
D. X-rays
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Italicized rationale: Alpha particles are heavy, positively
charged, and have very low penetration power.
3. The SI unit of absorbed dose is:
A. Sievert
B. Gray
C. Roentgen
D. Becquerel
Italicized rationale: The gray (Gy) measures absorbed
dose, defined as joules per kilogram.
4. Which biological effect of radiation has a threshold dose?
A. Stochastic effects
B. Deterministic effects
C. Genetic mutations
D. Cancer induction
Italicized rationale: Deterministic effects occur only after
a threshold dose is exceeded and severity increases with
dose.
5. A worker’s personal dosimeter measures:
A. Activity
B. Exposure rate
C. Individual radiation dose
D. Half-value layer
Italicized rationale: Dosimeters are designed to record
cumulative occupational dose.
6. The half-life of a radionuclide refers to the time required
for:
A. All atoms to decay
B. Activity to double
C. Half of the radioactive atoms to decay
D. Radiation to stop
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Italicized rationale: Half-life is a fundamental property
describing radioactive decay.
7. Which factor most strongly affects external radiation
exposure?
A. Age of the worker
B. Distance from the source
C. Gender
D. Body mass
Italicized rationale: According to the inverse square law,
increasing distance significantly reduces exposure.
8. Which radiation type is most penetrating?
A. Alpha
B. Beta
C. Gamma
D. Neutron (thermal)
Italicized rationale: Gamma rays are highly penetrating
electromagnetic radiation.
9. The unit of radioactive activity is:
A. Gray
B. Sievert
C. Becquerel
D. Coulomb
Italicized rationale: The becquerel (Bq) represents one
disintegration per second.
10. Which organ is most radiosensitive?
A. Muscle
B. Bone marrow
C. Skin
D. Liver
Italicized rationale: Rapidly dividing tissues such as bone
marrow are highly radiosensitive.
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11. Increasing kVp in diagnostic radiography primarily
affects:
A. Image contrast only
B. Beam penetration and patient dose
C. Exposure time only
D. Film processing
Italicized rationale: Higher kVp increases photon energy,
penetration, and scatter dose.
12. Which shielding material is most effective against X-
rays?
A. Plastic
B. Glass
C. Lead
D. Wood
Italicized rationale: Lead’s high atomic number makes it
ideal for attenuating X-rays.
13. A stochastic effect of radiation exposure is
characterized by:
A. Severity increasing with dose
B. Probability increasing with dose
C. Presence of a threshold
D. Immediate onset
Italicized rationale: Stochastic effects have no threshold;
probability rises with dose.
14. Occupational dose limits are established to:
A. Eliminate radiation exposure
B. Reduce risk to acceptable levels
C. Maximize image quality
D. Increase productivity
Italicized rationale: Dose limits balance benefit and
acceptable risk.
RADIATION SAFETY (AMMO 66)
FINAL COMPREHENSIVE EXAM ALL
QUESTIONS AND CORRECT
DETAILED ANSWERS |LATEST 2026-
2027 VERSION | ALREADY A GRADED
1. A radiologic technologist reduces fluoroscopy time during
a procedure primarily to adhere to which radiation safety
principle?
A. Dose limitation
B. ALARA
C. Justification
D. Optimization
Italicized rationale: ALARA (As Low As Reasonably
Achievable) emphasizes minimizing exposure time,
increasing distance, and using shielding to reduce
radiation dose.
2. Which type of radiation has mass and charge and is stopped
by a sheet of paper?
A. Alpha particles
B. Beta particles
C. Gamma rays
D. X-rays
,2|Page
Italicized rationale: Alpha particles are heavy, positively
charged, and have very low penetration power.
3. The SI unit of absorbed dose is:
A. Sievert
B. Gray
C. Roentgen
D. Becquerel
Italicized rationale: The gray (Gy) measures absorbed
dose, defined as joules per kilogram.
4. Which biological effect of radiation has a threshold dose?
A. Stochastic effects
B. Deterministic effects
C. Genetic mutations
D. Cancer induction
Italicized rationale: Deterministic effects occur only after
a threshold dose is exceeded and severity increases with
dose.
5. A worker’s personal dosimeter measures:
A. Activity
B. Exposure rate
C. Individual radiation dose
D. Half-value layer
Italicized rationale: Dosimeters are designed to record
cumulative occupational dose.
6. The half-life of a radionuclide refers to the time required
for:
A. All atoms to decay
B. Activity to double
C. Half of the radioactive atoms to decay
D. Radiation to stop
,3|Page
Italicized rationale: Half-life is a fundamental property
describing radioactive decay.
7. Which factor most strongly affects external radiation
exposure?
A. Age of the worker
B. Distance from the source
C. Gender
D. Body mass
Italicized rationale: According to the inverse square law,
increasing distance significantly reduces exposure.
8. Which radiation type is most penetrating?
A. Alpha
B. Beta
C. Gamma
D. Neutron (thermal)
Italicized rationale: Gamma rays are highly penetrating
electromagnetic radiation.
9. The unit of radioactive activity is:
A. Gray
B. Sievert
C. Becquerel
D. Coulomb
Italicized rationale: The becquerel (Bq) represents one
disintegration per second.
10. Which organ is most radiosensitive?
A. Muscle
B. Bone marrow
C. Skin
D. Liver
Italicized rationale: Rapidly dividing tissues such as bone
marrow are highly radiosensitive.
, 4|Page
11. Increasing kVp in diagnostic radiography primarily
affects:
A. Image contrast only
B. Beam penetration and patient dose
C. Exposure time only
D. Film processing
Italicized rationale: Higher kVp increases photon energy,
penetration, and scatter dose.
12. Which shielding material is most effective against X-
rays?
A. Plastic
B. Glass
C. Lead
D. Wood
Italicized rationale: Lead’s high atomic number makes it
ideal for attenuating X-rays.
13. A stochastic effect of radiation exposure is
characterized by:
A. Severity increasing with dose
B. Probability increasing with dose
C. Presence of a threshold
D. Immediate onset
Italicized rationale: Stochastic effects have no threshold;
probability rises with dose.
14. Occupational dose limits are established to:
A. Eliminate radiation exposure
B. Reduce risk to acceptable levels
C. Maximize image quality
D. Increase productivity
Italicized rationale: Dose limits balance benefit and
acceptable risk.
