Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Imaging > Lecture 9- Radiation Safety > Flashcards

Lecture 9- Radiation Safety Flashcards

1
Q

what is the biggest source of radiation to the US momulation

A

radon or medical imaging

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the biggest source of radiation to the US momulation

A

radon or medical imaging

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is the difference between Denver and New ORleans

A

Denver has more radiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is the typical annual radiation to a human

A

.2mSV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is cosmic radiation

A

cosmic ray particles originate from outside the solar system and from solar flares. When striking the earths upper atmosphere, particles are defected by van Allen belts. Radiation at Earths surface includes primary ET radiation secondary radiation showers which are particles from the upper atmosphere having collisions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

does radiation decrease with elevation

A

no it doubles every 5000 feet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

is exposure higher with air travel

A

yes, and frequent fliers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how much extra radiation do airline crews and frequent fliers recieve

A

1mSv annullay

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

is radiation higher at equator or poles

A

it is higher at the poles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the dose percent decrease between indoor and outdoor

A

indoor is 20% less than outside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is terrestrial radiation

A

radioactive things in the soli and primordial radionucelotides. Radioactive atoms with half-lives comparable to the age of the earth.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what primordial radio nucleotides are most radioactive

A

K-40 and uranium 238 and thorium 232

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is beta radiation

A

it is electrons like aluminum foil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is beta radiation

A

it is electrons like aluminum foil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the difference between Denver and New ORleans

A

Denver has more radiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is the typical annual radiation to a human

A

.2mSV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is cosmic radiation

A

cosmic ray particles originate from outside the solar system and from solar flares. When striking the earths upper atmosphere, particles are defected by van Allen belts. Radiation at Earths surface includes primary ET radiation secondary radiation showers which are particles from the upper atmosphere having collisions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

does radiation decrease with elevation

A

no it doubles every 5000 feet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

is exposure higher with air travel

A

yes, and frequent fliers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

how much extra radiation do airline crews and frequent fliers recieve

A

1mSv annullay

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

is radiation higher at equator or poles

A

it is higher at the poles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is the dose percent decrease between indoor and outdoor

A

indoor is 20% less than outside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is terrestrial radiation

A

radioactive things in the soli and primordial radionucelotides. Radioactive atoms with half-lives comparable to the age of the earth.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what primordial radio nucleotides are most radioactive

A

K-40 and uranium 238 and thorium 232

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is alpha radiation

A

helium nun which is lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what is beta radiation

A

it is electrons like aluminum foil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

hw does the radiation from the terrrestrial sources get into the body

A

into the lungs because partcles are inhaled from the soil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

how does radon usually get into the body and what kind of radiation is it

A

alpha radiatin and it is breathed in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what is the largest background source of radiation

A

radon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what is radon from and the half life

A

it is from uranium 238 and it is from alpha decay with a half life of 3.8 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what building feature is important for radon exposure

A

ventilation is important

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what unit are radon levels measured

A

it is measured through picoCuries per Liter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what is the disadvantages to film badge

A

requires processing and no direct readout, and excessive moisture and heat may damage the film

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what is the primary internal radiation and where is it found

A

muscle and pottasium-40

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what are the highest source of artificial radiation

A

medical exposures and mostly diagnostic xrays

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what causes cigarettes to be radioactive

A

they have polonium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

what is the dose from cigarettes

A

it is usually 16- mSV to bronchial epithelium and 13 mSV effective dose. More than a CT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what occupation has the highest occupational exposure and how does that compare to people working in radiology

A

uranium miners have 12 mSV as dose and radiologists and radiology techs are 1-.7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what is the typical dose for a an interventional radiologist and cardiac cath lab staff

A

it is 18 and 5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

where do you wear a personal dosimeter

A

front torso when no apron or collar with apron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

what are the three main types of peronnel dosimeters

A

film badges, storage phosphor dosimeters, pocket dosimeters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

how does a film badge work

A

radiation darkens the film proportional to the dose. Energy of radiation is determined by including metal filters in front of part of the film.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

what does the report include for film badges

A

a shallow does (skin dose) and beta radiation. It has a deep dose which is penetrating radiation and includes X-ray

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

what are the advantages of a film badge

A

wide recorded exposure range, durable and rugged, permanent record, and economical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

what is the range for x-rays and beta radiation of a film badge

A

xray is 100uSV-15SV

beta radiation- 500uSV-10SV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

what is the disadvantages to film badge

A

requires processing and no direct readout, and excessive moisture and heat may damage the film

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

what are storage phosphor dosimeteres

A

includse a material that traps radiation even in excited energy state. Some storage process with trap plus record event and event changing electronstrugcture energy is given off proportional todos record

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

what materials are used

A

TLD- lithium fluoride, and OSL which is aluminum oxide activated with carbon. Both types are configured with filters for radiation energy determination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

what is the advantage to storage phosphor dosimeters

A

wide recorded energy range and can be reused. It is 10uSV to 10SV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

what is the disadvantage to storage phosphor dosimeters

A

requires processing-no direct readout, destructive readout for TLD and OSL can be verified by repeating a few times. higher cost than film

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

what is a pocket dosimeter

A

used for high exposure situations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

what are the types of pocket dosimeters

A

G-M tubes, radiation, ion chamber, sensitive diodes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

what is the main region for the gas filled detector

A

it is the geiger muller region draw it and it is the cascade of events happen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

what are the disadvantages

A

initial cost

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

make a summary chart for these

A

see slide on the 11 page

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

how does gas-filled detector work

A

gas is ionized by radiation ions are collected and converted to signal. Incoming radiation ionizes the gas and converted to electrical signal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

how does a scintillator work

A

there is emission of light from radiation interactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

how does a semi-conductor reactor work

A

they are semi-conductor crystals of Silcon or geranium with impurities so they act as a diode and allows current flow after a radiation interaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

what are the types of detector in terms of usage

A

counters, spectrometers, dosimeters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

what is a counter detector

A

determines the number of radiation interactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

what are spectrometers

A

they determine the energy distribution or spectra of radiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

what are dosimeters in terms of use

A

determine total energy deposited by many interactions

63
Q

how does a gas filled detector work

A

two electrons with voltage applied and radiation forms ion pairs with gas and this charge is collected by electrodes and is calibrated by meter

64
Q

what is an example of ionization chamber

A

nuclear medicine survey meter, and x-ray exposure meter

65
Q

what are the issues with the amount of electrical charge felt by gas-filled detectors

A

gas filled are different based on electrical charge carried. IF there is not enough voltage then there is too little. Want to hit the proportional region where single is determinedly voltage but area lower were radiation is only factor.

66
Q

what is the main region for the gas filled detector

A

it is the geiger muller region draw it and it is the cascade of events happen

67
Q

what does the detector absorption of radiation depend on

A

photon energy
detector atomic number
detector density
detector thickness

68
Q

describe a scintillation detector

A

it emits UV or visible light after interaction. Interaction raises electrons to excited energy level, light emitted when electrons fall back to lower energy level.

69
Q

what is the difference between phosphorescence and flourescence

A

fluoro is prompt emission

phosphorescence- delayed emission

70
Q

what are trapped electron scintillarotsi

A

after interaction, electrons remain trapped in excited state until heated or scanned with laser. Thermoluminescent dosimeters- used for personnel Photostimulabel phosphorus used as imaging plates for computed radiography

71
Q

what are modes of detector operation

A

current mode which individual interactions are averaged together. Pulse mode each interaction is processed individually. Dead time can be problematic. 2 interactions must be separated by a finite time interval to produce distinct signals. iF a second interaction occurs during the dead time interval following another interaction, it is not counted and may disrupt the operation of the detector

72
Q

what is dead time for non-paralyzable

A

it is high interaction rates and detector resprtss an underestimated signal

73
Q

what is dead time for paralyzable

A

it is a high interaction rates, detector reports that no radiation is present

74
Q

detection efficiency is measured by

A

number detected/number emitted or efficiency= geometric efficiency times intrinstic efficiency

75
Q

what is geometric efficiency

A

fraction of photons emitted that reach the detector

76
Q

what is intrinsic efficiency

A

fraction of photons reaching the detector that are absorbed

77
Q

what is geometric efficiency dependent on

A

it is dependent on size of detector, shape and proximity to the source of radiation

78
Q

what is the best for increasing geometric efficiency

A

it is best if it is in a well, so if it is put in a box it is best

79
Q

what is intrinsic efficiency

A

it depends on how well the detector absorbs radiation, which is a factor of photon energy, detector atomic number, detector density and detector thickness

80
Q

what does radiation protection and control depend on

A

time, distance, shielding

81
Q

how do you minimize time

A

minimize the fluoroscopy on time and image acquisition. Exposure should not be activated if unprotected individuals are in the procedure room. Leave the procure room during exposure when possible, particularly image acquisition

82
Q

how do you control for distance

A

radiation source is like a point at the center of a sphere. Exposure is determined by the inverse square law

83
Q

what is the formula for the inverse square law

A

it is E2=E1(D1/D2)squared

84
Q

what can you do to help with shielding

A

material absorebs radiation abd best protection is by distance and shielding.

85
Q

what are the two types of shields

A

structural and personnel protection devic

86
Q

what do we do for CT rooms for structural shields

A

consider scatter and leakage only, primary beam is always intercepted

87
Q

what must the exposure no exceed for adjacent to x-ray rooms

A

50mSV for occupational workings, 1mSVper year for pibic or 20mSV in any hour for for other personnel or public

88
Q

what is the primary radiation

A

it is the useful beam

89
Q

what is the scatter radiation

A

it is the exposure rate for generally .1% and primary form patient to a 20x20 field size increases with field size

90
Q

what is the leakage radiation

A

xray is not in primary beam

91
Q

what are the design parameters

A

workload, use factor, occupancy factor, distance,

92
Q

what is the workload for shield

A

amount of X-rays produced

93
Q

what is the use factor for shield

A

fraction of time the radiation source is directed at specific surface

94
Q

what is the occupancy factor for shield

A

fraction of time someone occupies an adjacent area

95
Q

what is the distance for shield

A

from source to a specific surgace

96
Q

what do we do for radiography and fluoroscopy rooms for structural shields

A

if walls are gypsum, generally added lead is required but concrete or brick may be used

97
Q

what do we do for mammography rooms for structural shields

A

generally no lead is needed due to low X-ray energy an minimal scatter

98
Q

what do we do for CT rooms for structural shields

A

consider scatter and leakage only, primary beam is always intercepted

99
Q

what are lead gloves used for

A

they are used if the hangs are directly in the beam

100
Q

what is used to protect the thyroid

A

it is thyroid held and it is used if there is high exposure

101
Q

what is the mammography program under

A

MQSA

102
Q

what is the lead with lead glasses

A

it is optional use in high exposure situations, and side shields are important, but they can be heavy

103
Q

what can happen if the intervention radiologist doesn’t protect themselves with eye wear

A

it can lead to cataracts

104
Q

what are portable barriers and what are the specifications for it

A

it is transparent lead-acrylic plates which have .5-1mm lead equivalent. It is flor mounted or ceiling mountd or it can be on wheels. There can be lower body shelved for blocks and back scatter and tube leakage

105
Q

what can increasing tube filtration do to help

A

increasing tube filtration minimum HVL of 2.3 mm AL at 80 KVP required added filtration decreases the skin dose

106
Q

what does colimating to the body part do

A

it can reduce dose to areas outside the primary beam reduces scatter to improve image contrast

107
Q

do you shield the patient or use shields only for personell

A

it can be used for the rest of the patient too

108
Q

what should you do with source to patient distance

A

it should be increased to a certain dose so that patient is towards detector

109
Q

what is the recommended screen film speed

A

fast speed image receptor screen-film: 400 speed recommended and CR is 200 speed

110
Q

what should be implemented at the institution to prevent accidents

A

it is quality control to reduce errors

111
Q

what does NRC stand for and what does it do

A

it is the US nuclear regulatory commission- rgulates the nuclear materials, and agreement states can carry out NRC regulation enforcement. Rules include persona exposure monitoring, and radioisotope control and disposal, and personnel training, reporting misadministration

112
Q

what does the FDA do with this

A

it regulates radoopharmaceuticals and X-ray equipment maufacturers.

113
Q

what is the mammography program under

A

MQSA

114
Q

what is the dose limit to the whole body

A

50 mSV

115
Q

what is the dose limit to the individual organ

A

500 mSV

116
Q

what is the dose limit to the eye

A

150 mSV

117
Q

what is the dose limit to the skin

A

500 mSV

118
Q

what is an effective dose

A

it is a calculated quantity that reflects the radiation detriment of a non-uniform exposure in terms of a whole body exposure that would yield the same biological. Radiology takes in the radiation sensitivity

119
Q

what is the dose limit to embyro

A

5 mSV

120
Q

what is the dose limit to members of the public

A

1 mSV

121
Q

what is ALARA

A

it is dose limites that are not meant to be indications of what is considered safe. Radiation protection doctrine is ALARA. Radiation exposure is to be kept as low as reasonably achievable

122
Q

what does ALARA stand for

A

as low as reasonable achievable

123
Q

what are patients where patient dose is nescessary

A

after exposure, a patient discovered that they are pregnant, and research protocols to include the exposure to ionizing radiation, and regulatory requirements for mammography, and estimated skin dose to avoid radiation burns, and general patient requests

124
Q

what are the organ doses important

A

it is the dose absorbed by an organ, and energy imparted to organ/mass of organ, and it is used full for organ specific risk estimates/epidemiology, and unites are gray. typical are tends of grets

125
Q

what is the effective dose used for

A

it is only for reference phantom. It is organ estimated to these reference phantoms however, the tissue weighting factors are for a reference population of both genders and all ages. It is tissue weighting is not specific to gender but is an average. It has organ doses for these two phantoms are combined to calculate E. While organ dose estimates can be calculated for any phantom model or vowel data set, E is defined only for a singular reference person. E is not defined for any other phantom or person

126
Q

what is the equivalent dose

A

absorbed dose time radiation weighting factor

127
Q

what are the units for equivalent dose

A

it is from gray to sievert

128
Q

what is a radiation weighting factor

A

it is that there are different paths for each

129
Q

what is the difference between effective dose and equivalent dose

A

absorbed dose is in the diagnostic and effective dose is different

130
Q

what does the radiation weighting factor do

A

it rakes into account the type of radiation

131
Q

what does into calculating the effective dose

A

organ estimates, tissue weighting factors, and this means that it is not a physical quantity

132
Q

how are tissue weighting factors determined

A

it is for different tissues, the gonards, retinas and breast are more sensitive

133
Q

what is the MIRD

A

it is the medical internal radiation dosimetry

134
Q

what does MIRD do

A

it is the way that there is a 3D phantom and there is a weight of 70kg. It is good for standard anatomy and development

135
Q

what is an IRCP

A

it is a 3D model of things, and it is Ct image that adjusts for form as reference size and mass. It is for male and female. It is CT adjustments for organs. It helps calculate dose limits. Reference for genderless than gonads added

136
Q

what is the effective dose used for

A

it is only for reference phantom. It is organ estimated to these reference phantoms however, the tissue weighting factors are for a reference population of both genders and all ages. It is tissue weighting is not specific to gender but is an average. It has organ doses for these two phantoms are combined to calculate E. While organ dose estimates can be calculated for any phantom model or vowel data set, E is defined only for a singular reference person. E is not defined for any other phantom or person

137
Q

what is E used for

A

E is for occupational and public protection, but E has changed over time, and the definitions of weighting factors and calculation methodology have changed significantly twice since it was first introduced. E is not a physical parameters than can be measured of validated. E describes the radiation source, not the radiation recipient
E folds together cancer incidence and mortality

138
Q

what is E not for

A

it is NOT for estimating cancer risk, rather it is assesses detriment which includes much more than cancer risk. It is NOT for individuals, and not a patient dose, E is not sued for estimating potential numbers of cancers from small doses in a large population

139
Q

what is the process that this deposits energy in the issue during rad/fluoro

A

the uncharged particles like photons are transformed into kinetic energy of charged particles. Charged particles directly deposit their energy via excitation ionization or radiation. Energy deposition may be some distance from original interaction- two step reaction

140
Q

what is air kerma

A

kinetic energy released in air- one step reaction

141
Q

what is X-ray tube output

A

it is karma/mAs it is in units of mGY/mAs.

142
Q

what is the entrance skin dose

A

entrance skin dose- entrance skin karma times ratio ( tissue to air) of mass energy absorption coefficients

143
Q

what is the diagnostic reference levels

A

DRLs are a form of investigation level used as a simple test to identify situations where patient dose is unusally high. Employ an easily measured and standardized quantity. If consistntly exceeded, a local review of procedures and equipment should be performed. IF possible, dose reduction measures should be taken

144
Q

what is the entrance dose and effective dose for abdomen AP

A

entrance 2.6

effective .5

145
Q

what is the entrance dose and effective dose for extremity

A

entrance .1

effective

146
Q

what is the entrance dose and effective dose for skull (lateral)

A

entrance .7

effective .1

147
Q

what is the entrance dose and effective dose for bone survey

A

entrance 17

effective 2.8

148
Q

what is the entrance dose and effective dose for EXU (KUB+tomo)

A

entrance 38

effective 3.5

149
Q

what happens to the dose area product and effective dose for angiography exams

A

the increase the dose greatly

150
Q

what is the highest angiography exam

A

TIPS procedure

151
Q

does CT have a entrance skin dose

A

no. it just has an effective dose

152
Q

what is the compassion of patient specific risk

A

it is highly realistic virtual models of patients or the specific patients own CT or MRI data to define the tissues in the relevant organs. Performs a Monte Carlo simulation and calculate the organ doses. Refer to reference data on risk per unit absorbed dose to calculate risk on an organ by organ basis

153
Q

what does BEIR stand for

A

biological effects of ionizing radiation

Imaging (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions