RADIATION SAFETY EXAM #4
QUESTIONS AND ANSWERS
Federal law on radiation protection requires which two of the following? - Answer-
signage for radiation areas, maintaining personnel dose records
What is the dose limit for the lens of the eye for occupational workers in radiation per
The National Council on Radiation Protection and Measurements (NCRP) 116? -
Answer-150 millisieverts (mSv)
LD50/60 refers to the lethal dose of radiatin that will kill what percentage of the human
population and within how many days if no medical attention is provided? - Answer-50%
within 60 days
Coherent interactions typically occur with a beam carrying less than: - Answer-10
kiloelevtron volts (keV)
During the earliest phases of pregnancy, the embryo is: - Answer-sensitive to radiation
Which two of the following is accomplished with pulsed fluoroscopy? - Answer-
decreased patient dose, extended tube life
Which of the following should be avoided if possible when imaging morbidly obese
patient using direct radiography (DR) image receptors? - Answer-The use of full 17x17"
radiation field
The lifetime whole-body dose limit for a radiographer is calculated as: - Answer-Age x
10 millisieverts (mSv)
Minimized patient exposure can be achieved with the use of - Answer-well-calibrated
automatic exposure control (AEC)
Low-energy x-ray photons absorbed in the patient's skin will usually result in increased:
- Answer-patient exposure
Leakage radiation from the x-ray tube is limited to: - Answer-1 milligray/hour at 1 meter
A technologist standing 6 feet away from the C-arm unit receives an exposure rate of 4
microgray/hour. What will the exposure rate be if the technologist moves back a total of
12 feet from the C-arm unit? - Answer-1 microgray/hour
How does radiation exposure rate influence biological damage? - Answer-increased
exposure rate increases biological damage
,Which of the following may alert fluoroscopic x-ray production after a preset period of
time? - Answer-cumulative timer
The safety features of a fluoroscopic unit do not include a: - Answer-high-grid ratio
Radiation with a high rate of linear energy transfer (LET) will result in which three of the
following? - Answer-rapid energy deposition, concentrated tissue damage, increased
risk of biologic harm
The acronym ESE refers to: - Answer-Entrance skin exposure
Which two of the following factors have an impact on the quality of the x-ray beam? -
Answer-kilovoltage peak (kVp), filtration
Which of the following effects is most likely to occur at low doses of radiation? - Answer-
cancer
Which of the following classifications includes radiation-induced cancer? - Answer-
stochastic
Expectant mothers who are technologists should wear a fetal dosimeter at what
location? - Answer-at the waist
When comparing one type of radiation to another, the unit of measurement that can be
used to describe the biological effects is the: - Answer-Sievert
A characteristic photon is created by the interaction between an incident electron and
a(n) - Answer-inner-shell electron of tungsten
The National Council for Radiation Protection and Measurement (NCRP) requires that
leakage radiation from the fluoroscopic tube must be below: - Answer-1 milligray/hour at
1 meter from the tube
Which three of the following would be considered a secondary barrier? - Answer-walls
over 7 feet, control booth, lead apron
The acronym LET stands for: - Answer-Linear energy transfer
Increasing kilovoltage peak (kVp) results in which three of the following? - Answer-
increased photon quantity, increased photon energy, increased photon quality
The prefix "milli-" stands for - Answer-1/1000
What is the purpose of primary beam restriction? - Answer-keep the amount of tissue
irradiation to a minimum, improve iamge quality, reduce patient exposure, reduce
scatter production
, Another term that can be used for tissue reactions is - Answer-non-stochastic effect
Because of the line-focus principle, the effective focal spot size decreases with
decreasing: - Answer-target angle
The safety features of fluoroscopic equipment include all of the following EXCEPT: -
Answer-high grid ratio
Which of the following would provide fluoroscopic imaging personnel with the BEST
radiation protection opportunity? - Answer-Controlling the fluoroscopic system remotely
The International System of Units (SI) of measurement for exposure is: - Answer-
Coulomb per kilogram (C/kg)
When ionization occurs, which of the following is separated from the atom? - Answer-
Electron
The International System of Units (SI) for absorbed dose is: - Answer-Gray (GY)
X-ray photons that do not have the energy to penetrate the patient will result in: -
Answer-Increased patient skin dose
During Compton interactions, the incident x-ray photon interacts with what portion of an
atom? - Answer-outer-shell electron
Epilation may begin to occur in most people following a radiation exposure of at least: -
Answer-3,000 milligray (mGy)
Which of the following is a type of ionizing radiation? - Answer-X-rays
What thickness of protective shielding is required in the Bucky slot cover of a
fluoroscopic imaging unit? - Answer-0.25 mm lead equivalent
What effect does decreasing the primary beam field size (increasing collimation) have
on the amount of scatter radiation reaching the image receptor (IR)? - Answer-
decreases amount of scatter radiation reaching the IR
Equivalent dose is measured in: - Answer-Millisieverts (mSv)
What stage of embryonic development takes place from 10 days to 6 weeks post-
conception? - Answer-organogenesis
Which of the following is the most commonly used beam restricting device? - Answer-
collimator
QUESTIONS AND ANSWERS
Federal law on radiation protection requires which two of the following? - Answer-
signage for radiation areas, maintaining personnel dose records
What is the dose limit for the lens of the eye for occupational workers in radiation per
The National Council on Radiation Protection and Measurements (NCRP) 116? -
Answer-150 millisieverts (mSv)
LD50/60 refers to the lethal dose of radiatin that will kill what percentage of the human
population and within how many days if no medical attention is provided? - Answer-50%
within 60 days
Coherent interactions typically occur with a beam carrying less than: - Answer-10
kiloelevtron volts (keV)
During the earliest phases of pregnancy, the embryo is: - Answer-sensitive to radiation
Which two of the following is accomplished with pulsed fluoroscopy? - Answer-
decreased patient dose, extended tube life
Which of the following should be avoided if possible when imaging morbidly obese
patient using direct radiography (DR) image receptors? - Answer-The use of full 17x17"
radiation field
The lifetime whole-body dose limit for a radiographer is calculated as: - Answer-Age x
10 millisieverts (mSv)
Minimized patient exposure can be achieved with the use of - Answer-well-calibrated
automatic exposure control (AEC)
Low-energy x-ray photons absorbed in the patient's skin will usually result in increased:
- Answer-patient exposure
Leakage radiation from the x-ray tube is limited to: - Answer-1 milligray/hour at 1 meter
A technologist standing 6 feet away from the C-arm unit receives an exposure rate of 4
microgray/hour. What will the exposure rate be if the technologist moves back a total of
12 feet from the C-arm unit? - Answer-1 microgray/hour
How does radiation exposure rate influence biological damage? - Answer-increased
exposure rate increases biological damage
,Which of the following may alert fluoroscopic x-ray production after a preset period of
time? - Answer-cumulative timer
The safety features of a fluoroscopic unit do not include a: - Answer-high-grid ratio
Radiation with a high rate of linear energy transfer (LET) will result in which three of the
following? - Answer-rapid energy deposition, concentrated tissue damage, increased
risk of biologic harm
The acronym ESE refers to: - Answer-Entrance skin exposure
Which two of the following factors have an impact on the quality of the x-ray beam? -
Answer-kilovoltage peak (kVp), filtration
Which of the following effects is most likely to occur at low doses of radiation? - Answer-
cancer
Which of the following classifications includes radiation-induced cancer? - Answer-
stochastic
Expectant mothers who are technologists should wear a fetal dosimeter at what
location? - Answer-at the waist
When comparing one type of radiation to another, the unit of measurement that can be
used to describe the biological effects is the: - Answer-Sievert
A characteristic photon is created by the interaction between an incident electron and
a(n) - Answer-inner-shell electron of tungsten
The National Council for Radiation Protection and Measurement (NCRP) requires that
leakage radiation from the fluoroscopic tube must be below: - Answer-1 milligray/hour at
1 meter from the tube
Which three of the following would be considered a secondary barrier? - Answer-walls
over 7 feet, control booth, lead apron
The acronym LET stands for: - Answer-Linear energy transfer
Increasing kilovoltage peak (kVp) results in which three of the following? - Answer-
increased photon quantity, increased photon energy, increased photon quality
The prefix "milli-" stands for - Answer-1/1000
What is the purpose of primary beam restriction? - Answer-keep the amount of tissue
irradiation to a minimum, improve iamge quality, reduce patient exposure, reduce
scatter production
, Another term that can be used for tissue reactions is - Answer-non-stochastic effect
Because of the line-focus principle, the effective focal spot size decreases with
decreasing: - Answer-target angle
The safety features of fluoroscopic equipment include all of the following EXCEPT: -
Answer-high grid ratio
Which of the following would provide fluoroscopic imaging personnel with the BEST
radiation protection opportunity? - Answer-Controlling the fluoroscopic system remotely
The International System of Units (SI) of measurement for exposure is: - Answer-
Coulomb per kilogram (C/kg)
When ionization occurs, which of the following is separated from the atom? - Answer-
Electron
The International System of Units (SI) for absorbed dose is: - Answer-Gray (GY)
X-ray photons that do not have the energy to penetrate the patient will result in: -
Answer-Increased patient skin dose
During Compton interactions, the incident x-ray photon interacts with what portion of an
atom? - Answer-outer-shell electron
Epilation may begin to occur in most people following a radiation exposure of at least: -
Answer-3,000 milligray (mGy)
Which of the following is a type of ionizing radiation? - Answer-X-rays
What thickness of protective shielding is required in the Bucky slot cover of a
fluoroscopic imaging unit? - Answer-0.25 mm lead equivalent
What effect does decreasing the primary beam field size (increasing collimation) have
on the amount of scatter radiation reaching the image receptor (IR)? - Answer-
decreases amount of scatter radiation reaching the IR
Equivalent dose is measured in: - Answer-Millisieverts (mSv)
What stage of embryonic development takes place from 10 days to 6 weeks post-
conception? - Answer-organogenesis
Which of the following is the most commonly used beam restricting device? - Answer-
collimator
