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