Radiation Safety and Radiobiology in Medical Imaging, 10th Edition (Sherer &
Visconti)
Chapter 1: Introduction to Radiation Protection (Questions 1–8)
Q1. The primary biomedical rationale for radiation protection is to:
A. Reduce equipment costs
B. Prevent the occurrence of deterministic effects and limit the probability of
stochastic effects
C. Eliminate all patient radiation exposure
D. Increase imaging speed
Answer: B. Prevent the occurrence of deterministic effects and limit the
probability of stochastic effects
Rationale: The entire framework of radiation protection is based on preventing
deterministic (tissue reaction) effects, which have a threshold, and reducing the
probability of stochastic effects (cancer, genetic effects), which are assumed to
have no threshold .
Q2. Which organization is primarily responsible for regulating the use of ionizing
radiation in medical imaging in the United States?
,A. The National Council on Radiation Protection and Measurements (NCRP)
B. The International Commission on Radiological Protection (ICRP)
C. The U.S. Nuclear Regulatory Commission (NRC) and individual state agencies
D. The Food and Drug Administration (FDA) only
Answer: C. The U.S. Nuclear Regulatory Commission (NRC) and individual state
agencies
Rationale: The NRC regulates the use of byproduct material (radioisotopes) while
individual states regulate the use of x-ray equipment through agreement state
programs or directly. The FDA also has authority over equipment performance
standards .
Q3. The ALARA principle stands for:
A. As Low as Reasonably Achievable
B. Always Lower All Radiation Amounts
C. As Long as Radiation is Avoided
D. Allow Limited Annual Radiation Amounts
Answer: A. As Low as Reasonably Achievable
,Rationale: ALARA is the central philosophy of radiation protection, meaning
economic and social factors are considered while keeping radiation doses as low
as reasonably achievable. It applies to both occupational and medical exposure .
Q4. Which of the following is an example of a deterministic effect of radiation
exposure?
A. Cancer
B. Genetic mutation
C. Skin erythema (reddening)
D. Leukemia
Answer: C. Skin erythema (reddening)
Rationale: Deterministic effects (tissue reactions) have a threshold dose and
increase in severity with increasing dose. Skin erythema, epilation (hair loss), and
cataracts are classic deterministic effects. Cancer and genetic effects are
stochastic (probabilistic) effects.
Q5. The "as low as reasonably achievable" (ALARA) concept is applied to which of
the following?
, A. Occupational exposure only
B. Medical exposure of patients only
C. Public exposure only
D. All radiation exposure situations
Answer: D. All radiation exposure situations
Rationale: The ALARA principle applies broadly to all exposure situations—
occupational, medical, and public—incorporating economic and societal factors
while striving to keep doses as low as achievable .
Q6. Which of the following is NOT a cardinal principle of radiation protection?
A. Time
B. Distance
C. Shielding
D. Collimation
Answer: D. Collimation
Visconti)
Chapter 1: Introduction to Radiation Protection (Questions 1–8)
Q1. The primary biomedical rationale for radiation protection is to:
A. Reduce equipment costs
B. Prevent the occurrence of deterministic effects and limit the probability of
stochastic effects
C. Eliminate all patient radiation exposure
D. Increase imaging speed
Answer: B. Prevent the occurrence of deterministic effects and limit the
probability of stochastic effects
Rationale: The entire framework of radiation protection is based on preventing
deterministic (tissue reaction) effects, which have a threshold, and reducing the
probability of stochastic effects (cancer, genetic effects), which are assumed to
have no threshold .
Q2. Which organization is primarily responsible for regulating the use of ionizing
radiation in medical imaging in the United States?
,A. The National Council on Radiation Protection and Measurements (NCRP)
B. The International Commission on Radiological Protection (ICRP)
C. The U.S. Nuclear Regulatory Commission (NRC) and individual state agencies
D. The Food and Drug Administration (FDA) only
Answer: C. The U.S. Nuclear Regulatory Commission (NRC) and individual state
agencies
Rationale: The NRC regulates the use of byproduct material (radioisotopes) while
individual states regulate the use of x-ray equipment through agreement state
programs or directly. The FDA also has authority over equipment performance
standards .
Q3. The ALARA principle stands for:
A. As Low as Reasonably Achievable
B. Always Lower All Radiation Amounts
C. As Long as Radiation is Avoided
D. Allow Limited Annual Radiation Amounts
Answer: A. As Low as Reasonably Achievable
,Rationale: ALARA is the central philosophy of radiation protection, meaning
economic and social factors are considered while keeping radiation doses as low
as reasonably achievable. It applies to both occupational and medical exposure .
Q4. Which of the following is an example of a deterministic effect of radiation
exposure?
A. Cancer
B. Genetic mutation
C. Skin erythema (reddening)
D. Leukemia
Answer: C. Skin erythema (reddening)
Rationale: Deterministic effects (tissue reactions) have a threshold dose and
increase in severity with increasing dose. Skin erythema, epilation (hair loss), and
cataracts are classic deterministic effects. Cancer and genetic effects are
stochastic (probabilistic) effects.
Q5. The "as low as reasonably achievable" (ALARA) concept is applied to which of
the following?
, A. Occupational exposure only
B. Medical exposure of patients only
C. Public exposure only
D. All radiation exposure situations
Answer: D. All radiation exposure situations
Rationale: The ALARA principle applies broadly to all exposure situations—
occupational, medical, and public—incorporating economic and societal factors
while striving to keep doses as low as achievable .
Q6. Which of the following is NOT a cardinal principle of radiation protection?
A. Time
B. Distance
C. Shielding
D. Collimation
Answer: D. Collimation
