Safety Kettering Audio Flashcards
(177 cards)
1
Q
Definition of Thermionic Emission:
A
Boiling off of electrons, liberation of electrons
2
Q
Responsible for sending the current for thermionic emission to take place:
A
Filament Transformer or Step down transformer
3
Q
Electric potential/potential difference/source of EMF represents the unit of the:
A
Volt
4
Q
The unit of electric potential:
A
Volt
5
Q
What charge does the anode carry? positive or negative?
A
positive electrode
6
Q
What material makes up target surface?
A
Tungsten Target with Rhenium
Or
Tungsten
7
Q
The two components that make up the cathode:
A
filament wires and focusing cup
8
Q
What charge does the cathode carry? positive or negative?
A
negatively charged
9
Q
What material makes up the filament wires?
A
Thoriated Tungsten
10
Q
What material makes up the focusing cup?
A
molybdenum or nickle
11
Q
99% of the interaction process gets converted to:
A
Heat (Thermal Energy)
12
Q
Up to 1% gets converted to:
A
electromagnetic energy (x-ray photons)
13
Q
Electrons get converted to: (when they interact with the target surface):
A
x-ray photons
14
Q
When electrons interact with the target surface it is called the:
A
side of conversion
15
Q
Where do electrons get converted to x-ray photons?
A
the target surface
16
Q
Smallest subdivision of an element that maintains all the physical and chemical properties of the element:
A
Atom
17
Q
We know that protons are (+) positively charged, nuetrons are no charge or neutral and electrons are negatively charged within the nucleus we call them:
A
nucleons (properties of the nucleus)
18
Q
Upside down T is a symbol for:
A
Perpendicular Central Ray
19
Q
CR:
A
Central Ray
20
Q
IR:
A
Image Receptor
21
Q
z
A
Atomic number
22
Q
Atomic mass number (A) definition:
A
number of nucleons or number of protons + neutrons
23
Q
Atomic number (z) definition:
A
the number of protons in the nucleus
24
Q
the electrons and the protons are highley attracted to each other, how come the protons don’t fly out to see the electrons, how come the electrons do not fly inward:
A
Because you have two counteractive forces competing with each other, syntripical vs syntripical force.
25
The binding energy of the K-shell of Tungsten?
69.53 kEV or 70 kEV
26
What is the atomic number of Tungsten?
z=74 (74 protons 74 electrons)
27
The number of electrons in the last or outermost shell:
valence number
28
What is the maximum number of electrons you can have in the 3rd shell (M)?
2 (3)^2 2x9= 18 electrons
29
What is the maximum number of electrons in any one shell?
2n^2
30
What is the maximum number of electrons in the valance shell?
maximum of 8
31
The definition of Isotropic Emission:
X-rays are emitted by the focal spot in all directions
32
The definition of Attenuation:
The reduction of the intensity of the beam as it passes through matter
33
The definition of Ionization:
The removal of an orbital shell electron
34
An atom of tungsten, if ionization takes place and drop the electron. The previously uncharged atom will have an electrical charge. After ionization takes place what charge will the atom carry?
positively charged (74 protons 73 electrons)
35
In x-ray production when x-rays get produced/when x-rays get produced in the tube:
Bremsstrahlung
Characteristic
36
When x-rays interact with matter:
Compton
Coherent
Photoelectric
37
Projectile (high speed) electron interacts with the electrostatic field of the (tungsten) nucleus:
Bremsstrahlung
38
The projectile electron undergoes three processes:
Slows Down
Changes Direction
Loses some of its energy
39
When the electron becomes under the influence of the nucleus, what continues on:
the momentum effect of the production of an unknown ray (x-ray)
Bremsstrahlung x-ray emission*
40
Average x-ray energy beam about:
30% of peak
41
In order to produce characteristic radiation:
70 kV and above
42
If the technologist does a hand x-ray at 60 kVp:
the electron can not ionize an remove it
43
44
4 requirements of production x-rays:
Source of free electrons
Accelerate electrons across the tube
Focus the electrons
Deceleration
45
Send a current to the wire, the wire gets hot and electrons get boiled off through in the process of:
Thermionic Emission
46
The _____ determines the amount of current that will be sent to the filament (step down transformer)
MA
47
As the number of secondary turns decreases voltage:
Decreases
Current increases proportionally
48
Rhenium:
Bigger stronger faster to stand up to the high speed electrons bombarding it constantly
49
Atoms exist with a net nuetrality of:
0
50
We produce two types of radiation in the diagnostic imaging world;
Bremsstrahlung
Characteristic
51
When there is an interaction with the k-she’ll, ionization takes place and the L shell fills the void:
Characteristic Interaction
52
All photons always maintain four properties:
Frequency
Wavelength
Velocity
Amplitude
53
An x-ray is considered to be:
Photon
54
A light photon is considered an
X-ray
55
X-radiation is:
Electromagnetic Energy
56
Which of the following are examples of particulate radiation?
Alpha
Beta
57
The rate of the rise and fall or how often:
Frequency
58
The distance between two coressponding points:
Wavelength
59
At 60 kv; ______ wavelength, _____ frequency
Longer, lower
60
At 90 kV, ______ wavelength; ______ frequency
Shorter, higher
61
Is there a difference in velocity in a 60 kEV photon and a 90 kEV photon?
No difference
Velocity is a constant factor
62
X-ray photons move:
At the speed of light or not at all
63
What is the speed of light?
186,000 miles/second
3 x 10^8 meters per second
64
What is the relationship between wavelength and frequency?
Inversely proportional
As wavelength increases frequency decreases
65
What is the relationship between wavelength and energy?
Inversely proportional
As wavelength increase energy decrease
66
What is the relationship between frequency and energy?
Directly proportional
Increase frequency increase energy
67
Which controls the quality kvp or mAs?
kVp
68
Which controls the energy? kVp or mAs
kVp
69
Which controls the penetrability?
kVp
mAs
kVp
70
Which controls the quantity?
mAs
71
The rate of exposure:
mAs
72
The intensity of exposure?
mAs
73
Patient dose is: mAs or kVp
mAs
74
What controls the wavelength?
kVp
75
A Radiographic examination is performed with 70 kV, 10 mAs and a patient receives a dose of 18 C/kG (mR) a new exposure is made with 25 mAs to increase receptor exposure. What new intensity is to be delivered?
I1= 18 C/kg
I2= x
mAs1= 10 mAs
mAs2= 25 mAs
I1/I2= mAs1/mAs2
76
With the use of filters:
Increase quality and decrease quantity
77
Half-Value Layer definition:
Thickness of an absorbing material required to reduce x-ray intensity by one-half its original value
78
The amount of material necessary to reduce the intensity by 1/2 of its original value:
HVL
Half Value Layer
79
List the technical factors that affect HVL:
kVp
Filtration
80
The intensity is inversely proportional to the square of the distance
Inverse Square Law
81
If distance ever gets doubled or cut in half the intensity always gets changed:
By a factor of 4
4xs more
4xs less
82
If the patient is lying down on the table and they are your source of scatter if you are standing 40 inches away from the patient (100cm) your dose is 20 C/kg. 100 cm to 200 cm?
50 c/kg
83
A Radiographic examination is performed 80 kV, 20 mAs, 100 cm SID and the patient receives a dose of 15 C/kg. A new exposure is made with a 200 cm SID to reduce magnification. What is my new exposure/intensity/dose?
I1/I2 (D2/D1)^2
84
A Radiographic examination is performed with 80 kV 20 mAs with 100 cm SID. A new exposure is made with a 200 cm SID. What new technique can be used to maintain receptor exposure?
mAs1/mAs2 = (SID1/SID2)^2
Exposure Maintenance Formula
Direct Square Law
85
As useful radiation and consists of the x-ray photons directed through the x-ray tube’s window port in a direction toward the patient.
Pre-interaction (Primary Radiation)
86
The x-ray beam prior to the interaction with the patient:
Primary Radiation
87
Radiation that is emitted from atoms of matter after an x-ray photon from the primary beam interacts with matter (characteristic radiation)
Secondary Radiation
88
Also known as exit radiation
Remnant radiation
89
Image forming radiation
Remnant Radiation
90
Remnant radiation is also known as:
Exit radiation
91
A reduction in x-ray intensity as it passes through matter:
Attenuation
92
Fundamental properties of x-ray:
Power packed bundles of energy
Highly penetrating invisible rays that are a form of electromagnetic radiation
Herterogenous or polyenergetic (0 to peak 60)
X-rays travel in straight lines
Can ionize matter and release small amounts of energy upon passing through matter
Can produce chemical and biological changes
Produce secondary and scattered radiation
Travel at the speed of light 3 x 10^8 meters/second
No mass or electrical charge-not affected by electric or magnetic fields
93
A tech is exposed to 15 mGy/min for 7 minute flouro exam at 3 feet from the patient. What would the techs exposure be if he/she was 5 feet from the patient?
15 x 7 = 105 total exposure
105/x = 5^2/3^2
X= 37.8 Mgy
What would the exposure rate be at 5 feet?
15/x = 5^2/3^2
5.4 mGy/min
94
Where does the Compton interaction take place?
Outer shell electron
95
Partial absorption of the incident x-ray photon?
Compton
96
Who or what is your biggest source of scatter?
The patient
97
At what angle as your standing in the room at a flouroscopic situation, what angle would you receive the least amount of radiation as a technologist?
90 degree angle
Right angle
Perpendicular to the source
98
What is the maximum number of times an x-ray photon can be scattered before it loses all of its energy?
Twice (tube ounce theory)
99
Everytime an x-ray photon gets scattered it will leave with how much of its original intensity?
1/1000
.001
.1 %
100
One incoming, two leaving:
Compton
101
What photon will always have a longer wavelength in the Compton interaction?
Scattered photon because it is leaving with less energy that’s why it got deflected laterally
102
Which interaction is more prevelant? Compton or photoelectric?
Compton
103
The electron that you knock out on the edge of the Compton interaction is called:
Recoil or secondary electron
104
Incident photon interacts with an innermost shell electron of a target atom and removes an electron
Photoelectric
105
All of the remaining energy of an incident photon is transferred to the the ejected electron this is called:
Photoelectron
106
Which of the following is responsible of the patient dose effect?
Photoelectric effect
107
An incident photon interacts with an orbital shell electron, no ionization take place and no energy has been given up:
Coherent effect (classical)
108
An incident photon interacts with an orbital shell electron, no ionization take place and no energy has been given up:
Coherent effect (classical)
109
An incident photon interacts with an orbital shell electron, no ionization take place and no energy has been given up:
Coherent effect (classical)
110
Happens at very low x-rays less than 10 kEV:
Coherent (classical)
111
1% of x-rats incident on the patient reach the IR:
Differential Absorption
112
Difference is x-ray interaction by various body tissue:
Differential Absorption
113
X-ray image is formed by those x-rays that undergo photoelectric absorption and those that are transmitted to the image receptor:
Differential Absorption
114
As thickness increases (mass density):
Attenuation increases
The probability of photoelectric and Compton interactions increases, decreased x-ray transmission
115
How tightly compacted at the atomic level
Atomic number
116
Do you have different amounts of scatter with 10 cm of air vs 10 cm of bone?
No effect
Same amount of scatter
117
An atomical part that measured 10 cm and 20 cm which one has more scatter?
20 cm
118
100 Rads = _____ Gy
1 Gy
100/100= 1 Gy
Traditional number and multiply by .01
119
The unit of absorbed dose?
Gray
120
The unit of absorbed dose equivalent?
Sievert
Sv
121
Measurement of the biological effectiveness of radiation?
SV
Dose equivalent
122
Used in radiation protection only- measurement of occupational exposure
SV
123
If the radiation monitor of a radiation worker records that the worker received 2 mGy of x-rays, 1 mGy of fast neutrons, and 1 mGy of alpha particles, what is the absorbed dose equivalent for this worker?
2(1) + 1 (10) + 1 (20) = 32 mSv*
124
The unit of exposure in air:
C/kg (mc/kg) (uc/kg) or AIR KERMA
125
1st, 2nd, 3rd trimester, what is the most sensitive?
1st
126
1st, 2nd, 3rd trimester, what is the least resistant?
1st
127
X-ray QF:
1
128
Gamma ray QF:
1
129
Beta Particles QF
1
130
Protons QF:
2
131
Fast neutrons QF:
10
132
Alpha particle QF:
20
133
There is no safe dose:
Non-threshold
134
Used to compare the risk of cancer based on different types of radiation and different types of tissues:
Effective dose (SV)
135
KERMA stands for:
Kinetic energy released per unit mass
136
1 gy=
1 J/kg
137
Measures the ENERGY of ionizations in air:
AIR KERMA
138
Is the study of methods of interaction and the effects of ionizing radiation on living systems
Radiobiology
139
Some amount of radiaiton is required before a measurable effect can be detected
Threshold
140
Any given dose of radiation will yield some measurable effect
Non-threshold
141
Which number defines itself to be non-linear threshold? On the graph
3
142
Which number on the graph defines x-ray?
1 linear non-threshold
143
Cell division
Mitotic Activity
144
The more immature cell=
The more sensitive
145
Nerve and muscle cells:
Less sensitive
More radio resistant
146
What is the single most radio sensitive cell of the body?
Lymphocyte
147
Stem
Cell
Lymphocyte
Muscle
Nerve
List in order from least sensitive to greatest
Nerve
Muscle
Stem cells (intestinal crypt)
Lymphocyte
148
Stem
Cell
Lymphocyte
Muscle
Nerve
List in order from most sensitive to least sensitive
Lympcyte
Stem Cell (intestinal crypt)
Muscle
Nerve
149
Rate of energy deposited per unit track length through an absorber:
Linear energy transfer
150
Amount of radiation that is transferred to the body as the X-ray beam travels through the body
Linear Energy Transfer (LET)
151
What is the relationship between LET and RBE?
Directly proportional
152
Ability to produce biological damage
RBE
153
Diagnostic x-rays are considered: _____ LET radiaiton and _____ RBE
LOW, LOW
154
Defines the ability of aerobic conditions to enhance the effectiveness of radiation
Oxygen Effect
155
Which is more lethal
LD 50/30
LD 50/60
LD50/30
156
LD50/
Lethal dose of 50% of the population over a ____ number of days.
157
Equal doses of radiation that are delivered with time interval separations (time between exposures)
Fractionation
158
Radiation dose that is delivered continuously but at a loaner dose rate:
Protraction
159
Offers a cell the greatest ability to survive and recover from radiation exposure
Fractionation
160
Radiation interaction with water
Radiolysis
161
Radiation is:
Indirect interaction of biological damage
162
Free radicals can combine to form toxic substances such as:
Hydrogen peroxide
-OH* + OH = H2O2
163
Positive water molecule can split into a:
Free radical highly reactive and unstable substance
164
If what phases is the cell considered to be the most radiosensitive?
Metaphase
M-phase
During the cell division process
165
Cell division
Mitosis
166
Germ cell division
Miosis or meosis
167
What is a germ cell?
Sex cell
Reproductive cell
168
Mitotic activity resumes after a
Short delay
169
1 rad
1 Gy
.01 mGy
170
Is Mitotic delay considered to be a threshold or non threshold dose response?
Can occur at :01 gy or 10 mGy
Threshold!
171
Mitotic delay can occur at:
.01 Gy or 10 mGy
172
Reproductive failure can occur as little as:
1-10 Gy
173
Cell goes through one or more Mitotic phases and then dies
Mitotic (genetic) death
174
Phases of cell division in order
Prophase
Metaphase
Anaphase
Telophase
175
Master molecule or target molecule
Target
176
Somatic effect (changes)
Effect individual cell of the body
Cancer
177
A high radiation dose delivered to the long bones of the lower extremities that results in a suppression of the of the hemopoietic system and causes loss in the volume of circulating red blood cells in the body
General somatic effects
