Test Bank – 28 Questions with Rationales
📝 Multiple Choice Questions (1–15)
1. Which of the following best defines the ALARA principle?
A. A legal requirement for radiation workers
B. A method to increase diagnostic image quality
C. A principle that promotes minimizing radiation exposure
D. A guideline for maintaining radiation equipment
Answer: C
Rationale: ALARA (As Low As Reasonably Achievable) is the core
philosophy of radiation protection, encouraging professionals to always
minimize exposure while achieving necessary image quality.
2. Who holds the primary responsibility for protecting patients from
unnecessary radiation exposure?
A. The patient
B. The radiologic technologist
C. The radiologist
D. The manufacturer of imaging equipment
Answer: B
Rationale: Radiologic technologists are directly responsible for
positioning, technique selection, and shielding, making them key players
in radiation protection during procedures.
3. Which organization recommends dose limits for radiation workers
and the general public?
A. FDA
B. NRC
C. NCRP
D. OSHA
Answer: C
Rationale: The National Council on Radiation Protection and
Measurements (NCRP) develops guidelines on radiation dose limits and
protection measures.
4. The biological damage potential of ionizing radiation is primarily a
result of its ability to:
, A. Penetrate deeply into matter
B. Excite atomic nuclei
C. Ionize atoms within body tissues
D. Induce magnetic fields
Answer: C
Rationale: Ionization disrupts normal cellular functions by ejecting
electrons, leading to molecular damage.
5. Which of the following is NOT a goal of radiation protection?
A. Preventing deterministic effects
B. Eliminating radiation use in all procedures
C. Minimizing stochastic effects
D. Reducing unnecessary exposures
Answer: B
Rationale: Radiation is essential in medical imaging; the goal is not
elimination, but safe, justified, and optimized use.
6. Stochastic effects differ from deterministic effects in that they:
A. Have a threshold dose
B. Increase in severity with dose
C. Occur randomly without a threshold
D. Are always immediately observable
Answer: C
Rationale: Stochastic effects (like cancer) can occur from any dose,
without a known threshold, and the probability increases with exposure.
7. Which individual is most at risk of radiation-induced harm?
A. An elderly patient undergoing ultrasound
B. A radiographer who regularly uses fluoroscopy without shielding
C. A nurse in a general ward
D. A patient undergoing a chest X-ray
Answer: B
Rationale: Fluoroscopy involves continuous x-rays, and regular
unprotected exposure increases cumulative dose significantly.
8. The principle of justification in radiation protection implies:
A. Every exposure should be documented in writing
B. Only physicians can order imaging
C. A procedure should be performed only if the benefit outweighs the risk
D. Repeat imaging is never acceptable
Answer: C
, Rationale: Justification ensures that radiation is only used when there is a
valid clinical need, balancing benefits and risks.
9. Which term refers to the total sum of radiation exposure received by
a population?
A. Effective dose
B. Collective dose
C. Absorbed dose
D. Equivalent dose
Answer: B
Rationale: Collective dose is the sum of individual doses within a
specific group, often used for population-level risk assessments.
10. Radiation protection involves all of the following EXCEPT:
A. Time, distance, and shielding
B. Use of higher mA to shorten exposure
C. Removal of filtration from x-ray tubes
D. Monitoring radiation workers
Answer: C
Rationale: Filtration removes low-energy x-rays that increase patient
dose without improving image quality—so removing it is contrary to
protection principles.
11. Which group is most sensitive to ionizing radiation?
A. Middle-aged adults
B. Elderly patients
C. Children
D. Healthy athletes
Answer: C
Rationale: Children have rapidly dividing cells and a longer life span for
late effects to develop, increasing sensitivity.
12. The effective dose accounts for:
A. Exposure time only
B. Radiation type only
C. Tissue type and radiation type
D. Patient weight
Answer: C
Rationale: Effective dose considers both the type of radiation and the
sensitivity of tissues affected—offering a risk-adjusted measure of
exposure.