Radiation Safety Flashcards
Which photon beam energy has the highest HVL for the same absorber material?
A
250 KV
B
1.25 MV
C
511 KV
D
6 MV
D
6 MV
The probability of bremsstrahlung production:
A
Decreases with atomic number
B
Increases with atomic number
C
Is independent of atomic number
D
Decreases with the square of the atomic number
B
Increases with atomic number
What is the tolerance for the daily check of linac output constancy?
A
5%
B
1%
C
3%
D
2%
C
3%
Which of the following photon beam energies have the most desirable skin sparing effect?
A
4 MV
B
6 MV
C
150 KV
D
25 MV
D
25 MV
Which of the following would not be used in room shielding calculations?
A
Beam Energy
B
Use Factor
C
Inverse Square Law
D
Scatter-Air Ratio
E
Occupancy Factor
D
Scatter-Air Ratio
A Sievert (Sv) is ___?
A
100 ergs per gram
B
The SI unit of dose equivalent
C
Absorbed dose/RBE
D
The SI unit of exposure
The SI unit of dose equivalent
Which of the following can be used as a tissue compensator?
A
Shaped bolus
B
A wedge
C
Cerrobend
D
Dynamic MLC
E
All of the above
E
All of the above
Which of the following should be checked on a linac daily?
A
Light/radiation field coincidence
B
Beam flatness and symmetry
C
Field size indicators
D
None of the above
D
None of the above
Which of the following basic methods of protection is the most efficient way to increase protection from radiation?
A
Time
B
Distance
C
Shielding
D
Reduce beam energy
B
Distance
When calculating room shielding, what factor is defined by “the amount of time an adjacent room will be occupied”
A
Acceptable weekly dose (P)
B
Workload (W)
C
Barrier (U)
D
Occupancy (T)
D
Occupancy (T)
Radiation therapist control room is considered a:
A
Restricted area
B
Unrestricted area
C
Uncontrolled area
A
Restricted area
All of the following are components of Cerrobend EXCEPT:
A
Lead
B
Bismuth
C
Tin
D
Copper
D
Copper
Cadmium is used
Employees must be monitored for radiation exposure when they are expected to receive more than _____ of the effective dose equivalent.
A
5%
B
10%
C
15%
D
20%
B
10%
The HU for fat is:
A
-1000
B
-100
C
100
D
1000
B
-100
The spectrum of different shades of gray or contrast on a CT image is:
A
Window level
B
Window width
C
Field of view
D
Matrix
B
Window Width
The tolerance for gantry rotation check is:
A
3%
B
2%
C
1 degree
D
2 degrees
C
1 degree
Atoms with the same number of protons but different number of neutrons are called:
A
Isotope
B
Isobar
C
Isotone
D
Isomer
A
Isotope
Atoms with the same number of neutrons but different number of protons are called:
A
Isotope
B
Isobar
C
Isotone
D
Isomer
C
Isotone
The brachytherapy application method in which the radioactive source is placed within a body tube is:
A
Intracavitary
B
Interluminal
C
Interstitial
D
Intervascular
B
Interluminal
Which radioactive source has the shortest half-life ?
A
Radium
B
Cobalt
C
Strontium
D
Yttrium
D
Yttrium
The power source for the waveguide is:
A
Magnetron
B
Circulator
C
Modulator
D
Klystron
C
Modulator
The part of the linear accelerator that amplifies microwaves is:
A
Magnetron
B
Circulator
C
Modulator
D
Klystron
D
Klystron
The source of electrons in a linear accelerator:
A
Magnetron
B
Modulator
C
Electron gun
D
Accelerator guide
C
Electron gun
If the planned distance is 100 cm but the ODI on the patient reads 101.5 cm, what is the error?
A
An overdose of 3%
B
An overdose of 1.5%
C
An overdose of 1%
D
An underdose of 1.5%
E
An underdose of 3%
E
An underdose of 3%
Frequency and wavelength is inversely proportional.
A
True
B
False
A
True
Exposure is 400 mR at 90 cm. What will the exposure be at 180cm?
A
50 mR
B
200 mR
C
100 mR
D
150 mR
C
100 mR
: I(2)/I(1)= (D(1)/D(2))^2
x/400 = (90/180)^2
Which of the following has the highest quality factor?
A
X-ray
B
Alpha particles
C
Gamma rays
D
Neutrons
B
Alpha particles
The mAs setting primarily affects:
A
Image contrast
B
Image resolution
C
Patient dose
D
Image distortion
C
Patient dose
What are the tolerances for safety tests?
A
Functional
B
2 mm
C
Within 1%
D
Within 3%
A
Functional
How many HVLs are needed to reduce the beam to 6.25% it’s original value?
A
1
B
2
C
3
D
4
E
5
D
4
The most radiosensitive part of a cell is:
A
RNA
B
DNA
C
Mitochondria
D
Golgi apparatus
B
DNA
OER in human cells is:
A
1-1.5
B
2-2.5
C
2.5-3
D
3-4.5
C
2.5-3
How often should safety lights be checked?
A
Daily
B
Weekly
C
Monthly
D
Annually
A
Daily
The point on a dose-response relationship graph that represents the cells capability to repair:
A
Do
B
Dq
C
n
D
D37
B
Dq
he point on a dose-response relationship graph that shows the cells radiosensitivity:
A
Do
B
Dq
C
n
A
Do
An example of a stochastic effect:
A
Cancer
B
Erythema
C
Cataracts
D
Epilation
A
Cancer
A direct effect is when radiation hits:
A
DNA
B
RNA
C
Water
D
H202
A
DNA
The radiation unit that expresses the amount of radiation absorbed by a person is:
A
Gray
B
Rad
C
Sievert
D
Roentgen
C
Sievert
Which radiation instrument is used to find a source that has been misplaced
A
Geiger–Mueller counter
B
Thermoluminescent dosimeter
C
Diode
D
Optically Stimulated Luminescence
E
New Choice
A
Geiger–Mueller counter
Which radiation instrument is used to measure the production of radiation in a linear accelerator?
A
Geiger-Muller Detector
B
Thermoluminescent dosimeter
C
Diode
D
Ion chamber
D
Ion chamber
Which radiation instrument lights up to show radiation dose when heated?
A
GM detector
B
OSL
C
TLD
D
Farmer chamber
C
TLD
Which radiation instrument is used to check the linac’s beam output daily?
A
Diode
B
Farmer chamber
C
TLD
D
Film
A
Diode
Which radiation instrument is used to calibrate ion chambers in a linac?
A
Diode
B
TLD
C
OSL
D
Thimble chambers
D
Thimble chambers
The same beam flattening filter is used for all photon energies.
A
True
B
False
B
False
What is the main difference between gamma rays and x-rays?
A
Charge
B
Velocity
C
Origin
D
Frequency
C
Origin
Atoms that have the same atomic number and mass, but differ in the energy state is referred to as a(an:
A
Isomer
B
Isotone
C
Isobar
D
Isotope
A
Isomer
Elements with z numbers higher than ____ are more radioactive.
A
32
B
49
C
74
D
92
D
92
Which of the following radiation areas is typically accessible only to authorized personnel with specific training and authorization?
(Select all that apply)
A
Restricted area
B
Controlled area
C
Unrestricted area
D
Exclusion area
A
Restricted area
B
Controlled area
What is the purpose of the flattening filter in a linear accelerator?
A
To produce a uniform photon beam
B
To generate the electron beam
C
To shape and collimate the electron beam
D
To absorb unwanted low energy x-rays
A
To produce a uniform photon beam
Radioactivity emits all of the following EXCEPT:
A
Alpha particles
B
Beta particles
C
Photons
D
Gamma-Rays
C
Photons
Tandem and Ovoids are an example of what type of brachytherapy application method?
A
Interstitial
B
Intracavitary
C
Interluminal
D
Intervascular
B
Intracavitary
Which source of radiation is used in a nylon ribbon with an afterloader?
A
Gold
B
Palladium
C
Iodine
D
Iridium
D
Iridium
Which of the following statements about radiation exposure is true?
A
It is cumulative over a person’s lifetime
B
It decreases with decreasing distance from the radiation source
C
It has no health effects
D
New Choice
E
It is not influenced by the type of radiation
A
It is cumulative over a person’s lifetime
Which of the following statements about the ALARA principle is true?
A
It stands for “Average Limit of Acceptable Radiation Amounts”
B
It promotes the use of the highest possible radiation doses for IGRT
C
It emphasizes the need for radiation doses to be “as low as reasonably achievable”
D
It only applies to radiation therapy procedures
C
It emphasizes the need for radiation doses to be “as low as reasonably achievable”
What parameter is typically evaluated during the picket fence QA test?
A
Leaf positioning accuracy
B
Treatment time accuracy
C
Beam energy stability
D
Dose rate uniformity
A
Leaf positioning accuracy
The purpose of using a collimator during imaging is to:
A
Increase the radiation dose to the patient
B
Improve image contrast
C
Reduce patient motion blur
D
Limit the size and shape of the x-ray beam
D
Limit the size and shape of the x-ray beam
Which exposure factor primarily controls the quality or penetrating power of the x-ray beam in the diagnostic range?
A
kVp
B
mAs
C
SID
D
Grid ratio
A
kVp
When doubling the mAs, the resulting x-ray beam will have:
A
Four times the exposure
B
Half the exposure
C
Double the exposure
D
No change in exposure
C
Double the exposure
Which of the following examples requires a secondary radiation barrier?
(Select all that apply)
A
Primary electron beam
B
Primary photon beam
C
Scatter radiation
D
Leakage radiation
C
Scatter radiation
D
Leakage radiation
What is the primary purpose of radiation shielding in a linear accelerator vault?
A
To protect the linear accelerator from external interference
B
To regulate the temperature inside the vault
C
To minimize radiation exposure to patients and staff
D
To ensure proper airflow for equipment cooling
C
To minimize radiation exposure to patients and staff
Which material is commonly used for radiation shielding for a linear accelerator vault?
A
Concrete
B
Aluminum
C
Cerrobend
D
Steel
A
Concrete
Where should the radiation shielding be placed in a linear accelerator vault?
A
On the walls and ceiling
B
On the floor and walls
C
On the ceiling and floor
D
On the walls, floor, and ceiling
D
On the walls, floor, and ceiling
What is the purpose of safety lights in a linear accelerator room?
A
To provide ambient lighting during treatment
B
To indicate when the accelerator is operational
C
To signal potential hazards or unsafe conditions
D
To signal when treatment is completed
B
To indicate when the accelerator is operational
What is the purpose of the multileaf collimator (MLC) in the linac?
A
To shape and conform the electron beam
B
To shape and conform the photon beam
C
To shape and conform the imaging field for KV pairs
D
To reduce leakage radiation
B
To shape and conform the photon beam
What is the tolerance for localizing lasers for SRS/SBRT machines?
A
1 mm
B
1.5 cm
C
2 mm
D
1.5 cm
A
1 mm
What is the purpose of using a maze in a treatment vault?
A
To enhance treatment accuracy
B
To confine the beam to a point source
C
To reduce radiation scatter
D
To eliminate the need for primary barriers
C
To reduce radiation scatter
Which of the following is an important safety feature in a linac vault?
A
Large windows for natural lighting
B
Emergency stop buttons at multiple locations
C
Open access to treatment planning computers
D
Unrestricted access to the vault for patients and visitors
B
Emergency stop buttons at multiple locations
Which of the following is a natural source of radiation exposure?
A
Medical imaging
B
Nuclear power plants
C
Consumer products
D
Radon gas
D
Radon gas
What is the primary source of background radiation?
A
X-ray machines
B
Nuclear accidents
C
Cosmic radiation
D
Radiation therapy treatments
C
Cosmic radiation
Which method of radiation protection ins based on the inverse square law?
A
Time
B
Distance
C
Shielding
D
Attenuation
B
Distance
Which of the following is true about the effectiveness of shielding
A
The greater the shielding thickness, the greater the protection
B
The type of shielding material has no impact on its effectiveness
C
Shielding is only necessary for high-energy radiation sources
D
The amount of shielding doesn’t matter regardless of beam energy
A
The greater the shielding thickness, the greater the protection
How does increasing the distance from a radiation source affect radiation exposure?
A
It has no impact on radiation exposure
B
It decreases radiation exposure
C
It increases radiation exposure
D
It alters the type of radiation being emitted
B
It decreases radiation exposure
What is the tolerance for localizing lasers for IMRT machines?
A
1 mm
B
1.5 mm
C
2 mm
D
2.5 mm
B
1.5 mm
What is the primary purpose of personnel monitoring in radiation protection?
A
To determine the effectiveness of radiation shielding
B
To assess the occupational dose received by individuals
C
To measure the radiation output of imaging equipment
D
To monitor patient exposure during procedures
B
To assess the occupational dose received by individuals
What is the purpose of performing a star pattern test?
A
To evaluate the overall performance of the linear accelerator
B
To assess the accuracy and precision of gantry and collimator rotation
C
To measure the radiation output of the gantry and collimator
D
To monitor the treatment time during radiation delivery
B
To assess the accuracy and precision of gantry and collimator rotation
What type of radiation dose is typically monitored using personnel dosimeters?
A
Effective dose
B
Equivalent dose
C
Committed dose
D
Absorbed dose
B
Equivalent dose
Which of the following is NOT a recommended type of personnel dosimeter?
A
Film badges
B
Optically stimulated luminescence (OSL) dosimeters
C
Thermoluminescent dosimeters (TLDs)
D
Geiger-Muller counters
D
Geiger-Muller counters
Which component of a CT simulator converts x-rays into electrical signals?
A
X-ray tube
B
Detector array
C
Gantry
D
High voltage generator
B
Detector array
What action should be taken if a personnel dosimeter indicates an unexpectedly high radiation dose?
A
The dosimeter should be recalibrated immediately
B
The individual should stop working with radiation until the cause is investigated
C
The dosimeter should be discarded and a new one issued
D
The dose should be considered invalid and disregarded
B
The individual should stop working with radiation until the cause is investigated
Who is responsible for reviewing and maintaining personnel dosimetry records?
A
The radiation safety officer
B
The radiation oncologist
C
The medical physicist
D
The radiation therapist
A
The radiation safety officer
What type of radiation area has radiation levels that are expected to be within regulatory limits and poses minimal risk to individuals?
A
Restricted area
B
Controlled area
C
Unrestricted area
D
Exclusion area
C
Unrestricted area
Why is magnetic field screening necessary before entering an MRI room?
A
To ensure proper functioning of the MRI machine
B
To protect individuals from potential biological effects of the magnetic field
C
To prevent interference with electronic devices
D
To minimize the risk of allergic reactions to contrast agents
B
To protect individuals from potential biological effects of the magnetic field
Which component of the CT simulator allows for marking of the isocenter and/or treatment field?
A
Movable lasers
B
Detector array
C
High voltage generator
D
Slip rings
A
Movable lasers
What is the purpose of the safety questionnaire during magnetic field screening?
A
To assess an individual’s knowledge of MRI technology
B
To determine the individual’s eligibility for an MRI examination
C
To identify any potential safety concerns or contraindications
D
To evaluate the individual’s previous exposure to radiation
C
To identify any potential safety concerns or contraindications
What is the purpose of marking MRI-compatible equipment with specific labels or symbols?
A
To indicate the manufacturer of the equipment
B
To ensure proper handling and storage of the equipment
C
To identify equipment that is safe for use in the MRI environment
D
To track the maintenance history of the equipment
C
To identify equipment that is safe for use in the MRI environment
Which of the following is NOT a recommended practice for storing radioactive materials?
A
Keeping them in locked and labeled containers
B
Placing them in an open area for easy access
C
Storing them separately from non-radioactive materials
D
Ensuring proper shielding of the containers
B
Placing them in an open area for easy access
What is the equivalent of 1 Gray in Seiverts?
A
1 Sv
B
0.1 Sv
C
10 Sv
D
100 Sv
A
1 Sv
Which component in a linac generates the high-energy electron beam used to to create either a photon or electron beam?
A
Waveguide
B
Magnetron
C
Electron gun
D
Klystron
C
Electron gun
What is the purpose of the bending magnet or steering magnets in a linac?
A
To generate the electron beam
B
To collimate the photon beam
C
To rotate the gantry
D
To confine the electron beam
D
To confine the electron beam
How can the results of a picket fence QA test be used to improve MLC performance?
A
By adjusting the treatment time during MLC delivery
B
By calibrating the radiation output of the MLC
C
By identifying and correcting any MLC leaf positioning errors
D
By optimizing the treatment plan’s isodose distribution
C
By identifying and correcting any MLC leaf positioning errors
What is the role of ionization chambers?
A
To generate the electron beam
B
To measure background radiation during treatment
C
To measure the dose of radiation delivered to the patient
D
To rotate and shape the treatment beam
C
To measure the dose of radiation delivered to the patient
10 Sieverts is equivalent to how many rem?
A
0.1 rem
B
1 rem
C
100 rem
D
1000 rem
D
1000 rem
What is the tolerance for localizing lasers for non-IMRT machines?
A
1 mm
B
1.5 mm
C
2 mm
D
2.5 mm
C
2 mm
What is the primary component responsible for producing x-rays in the CT Simulation machine?
A
X-ray tube
B
Detector array
C
High voltage generator
D
Cooling system
A
X-ray tube
What s the purpose of the interlock system in a linear accelerator?
A
To ensure patient comfort during treatment
B
To monitor the treatment time
C
To prevent unsafe conditions and ensure patient and staff safety
D
To calibrate the radiation dose delivery
C
To prevent unsafe conditions and ensure patient and staff safety
How often should emergency switches be checked?
A
Daily
B
Weekly
C
Monthly
D
Annually
C
Monthly
1 rad is equivalent to how many Gray?
A
0.01 Gy
B
0.1 Gy
C
10 Gy
D
100 Gy
A
0.01 Gy
