Safety Questions Flashcards
1
Q
- Natural background radiation represents what percentage of humans’ radiation exposure?
a. 21% b. 50% c. 82% d. 5% - The greatest source of natural background radiation
exposure is: a. Cosmic rays b. Radioactive materials
c. The body itself d. Radon gas - Cosmic radiation:
a. Is present only in space
b. Is a source of exposure only to persons who lie in the sun
c. Is of concern only to space travelers
d. Is a part of natural background exposure
A
- B. Natural and artificial background are each approximately 50% of human’s exposure.
- D. Radon gas is part of humans’ natural background
exposure, which totals 50% of humans’ total exposure. - D. Earth’s atmosphere and magnetic fields help shield
us from cosmic radiation.
2
Q
- Radon gas:
a. Presents a danger when undetected
b. Is present in doses proportional to other sources
c. Is entirely human-made
d. Is the source of 100% of annual background dose - X-rays and gamma rays used in diagnostic imaging are:
a. Not of concern because the beam is filtered
b. Part of the natural background dose
c. Part of an artificial background radiation dose
d. An insignificant dose to the general population because they are used safely - A feature of fluoroscopic x-ray machines that automatically adjusts kVp and mA so as to maintain image brightness for necessary image quality is called:
a. Automatic imaging
b. Automatic brightness control (ABC)
c. Automatic image processing
d. Constant exposure output
A
- A. Radon gas may be present in homes, particularly
basements. Special kits should be used to determine
its presence.
C. Artificial, or human-made, radiation represents
close to 50% of the total human exposure.
- B.
3
Q
- What term best describes the approximate skin dose
where the x-ray beam is entering the patient?
a. Effective dose. b. Nonoccupational dose
c. In-air exposure d. Air kerma - Sievert is calculated by multiplying gray by
a. WR b. Wa c. Wt d. mAs - The total of air kerma over the exposed area of the
patient is called:
a. Dose area product b. Mean marrow dose
c. Genetically significant dose d. Total patient dose
A
- D. Air kerma is radiation depositing energy at a specific point.
- A. WR, radiation weighting factor.
- A.
4
Q
- Which of the following is also known as coherent scattering?
a. Photoelectric interaction. b. Compton interaction
c. Classical scatter d. Pair production - Which of the following photon–tissue interactions
does not occur in diagnostic radiography?
a. Photoelectric interaction b. Compton interaction
c. Coherent scatter d. Pair production - Which of the following is responsible for creating the
conditions for contrast on the image?
a. Photoelectric interaction b. Compton interaction
c. Coherent scatter d. Pair production
A
- C. This form of scatter has no effect on the image
below 70 kVp and does not cause ionization. It is negligible above 70 kVp. - D. Pair production occurs above 1.02 million electron
volts. - A. Photoelectric interaction results in absorption of
the incident, or incoming, x-ray photon. The difference between this interaction and the rays that pass
through the body unaltered to strike the image receptor is what provides contrast. Compton scatter, with
its resultant fog, certainly affects contrast, but it does
not produce contrast itself.
5
Q
- Which of the following produces scatter radiation
that exits the patient and may fog the image?
a. Photoelectric interaction b. Compton interaction
c. Coherent scatter d. Pair production - Which of the following produces scatter as a result of
vibration of orbital electrons?
a. Photoelectric interaction b. Compton interaction
c. Coherent scatter d. Pair production - Which of the following results in total absorption of
an incident x-ray photon?
a. Photoelectric interaction b. Compton interaction
c. Classic scatter d. Pair production
A
- B. Compton scatter that is not absorbed by a grid may
strike the image receptor and reduce contrast. - C. This is also known as classical or Thompson’s scattering. It has no effect on the image below 70 kVp. It
is negligible above 70 kVp. - A. This complete deposition of energy results in contrast being produced on the image.
6
Q
- Which of the following is the only photon–tissue
interaction that does not result in ionization?
a. Photoelectric interaction b. Compton interaction
c. Coherent scatter d. Pair production - Which of the following involves interaction between
an incident photon and an atomic nucleus?
a. Photoelectric interaction b. Compton interaction
c. Coherent scatter d. Pair production - Which of the following photon–tissue interactions
primarily involves K-shell electrons?
a. Photoelectric interaction b. Compton interaction
c. Coherent scatter d. Pair production
A
- C. No electrons are removed from the atoms being
struck. - D. Pair production occurs at megavoltage levels.
- A. Photoelectric effect occurs as incident photons
deposit their energy in the K-shell.
7
Q
- Which of the following primarily involves loosely
bound outer-shell electrons?
a. Photoelectric interaction b. Compton interaction
c. Coherent scatter d. Pair production - Which of the following results in the production of a
photoelectron that is ejected from the atom?
a. Photoelectric interaction b. Compton interaction
c. Coherent scatter d. Pair production - Which of the following photon–tissue interactions
necessitates the use of a grid?
a. Photoelectric interaction b. Compton interaction
c. Coherent scatter d. Pair production
A
- B. Compton interaction primarily involves outer shell
electrons, wherein both the electron and the photon
scatter, causing the atom to become ionized. - A. The inner shell electron is ejected, becoming a photoelectron. The atom becomes ionized.
- B. Because Compton interaction causes the production of scatter, a grid is needed to attempt to absorb the scatter before it reaches the image receptor.
8
Q
- Which of the following may result in occupational
exposure for a radiographer?
a. Photoelectric interaction b. Compton interaction
c. Coherent scatter d. Pair production - What unit of measurement is used for absorbed dose
in tissue?
a. Gya b. Gys c. Gyb d. Gyt - What unit of measurement is used for effective dose
limits?
a. Becquerel b. Gyt c. Sievert d. Gya
A
- B. Compton produces scatter, which during fluoroscopy or mobile procedures may expose the radiographer. Hence a lead apron is required when either one
is performed. - D. Gyt indicates gray in tissue.
- C.
9
Q
- Which of the following units would be used to describe the radiation present in a fluoroscopic room?
a. Bq b. Sv c. Gya d. Gyt - The amount of energy deposited by radiation per unit
length of tissue being traversed is:
a. LET, which determines the use of a WR when the equivalent dose is being calculated
b. Linear energy transfer
c. Higher for wave radiations than for particulate radiations
d. LET, which is expressed as a WR when absorbed dose is being calculated - What agency publishes radiation protection standards
based on scientific research?
a. Nuclear Regulatory Commission (NRC)
b. American Society of Radiologic Technologists
(ASRT)
c. National Council on Radiation Protection and
Measurements (NCRP)
d. Bureau of Radiological Health (BRH)
A
- C. Gray indicating absorbed dose, a indicating in air.
- A. Actually, choice B is a good choice as well, but A
is more complete. Remember, LET stands for linear
energy transfer. Choice C is incorrect because particulate radiations deposit more energy than wave
radiations. Choice D is incorrect because a radiation
weighting factor is used in the calculation of equivalent dose, not absorbed dose. Keep in mind that the
certification exam will require you to choose the one
best answer. - C. NCRP reports are the standards on which radiation protection practices are based.
10
Q
- The agency that enforces radiation protection standards relating to radioactive material at the federal level is the:
a. Nuclear Regulatory Commission (NRC)
b. International Commission on Radiation Protection (ICRP)
c. National Council on Radiation Protection and
Measurements (NCRP)
d. Bureau of Radiological Health (BRH) - Effective dose limit is defined as the upper boundary dose that:
a. Can be absorbed annually with a negligible risk of
somatic or genetic damage to the individual
b. Can be absorbed, either in a single exposure or
annually, with no risk of damage to the individual
c. Can be absorbed, either in a single exposure or
annually, with no risk of somatic or genetic damage to the individual
d. Can be absorbed, either in a single exposure
or annually, with a negligible risk of somatic or
genetic damage to the individual - ALARA is an acronym for:
a. As long as reasonably achievable
b. As little as reasonably achievable
c. As long as radiologist allows
d. A radiation protection concept that encourages radiation users to keep the dose to the patient as low as reasonably achievable
A
- A. The NRC has the authority to enforce radiation
protection standards relating to radioactive material. - D. Choice A is not as complete. Choices B and C are
incorrect because they imply that there is no risk of
damage to the individual. - D. ALARA stands for as low as reasonably achievable.
11
Q
- What are graphs called that show the relationship between dose of radiation received and incidence of effects?
a. Nonlinear-nonthreshold effect
b. Linear-nonthreshold effect
c. Radiation-effect curves
d. Dose-response curves - Which of the following is the basis for all radiation protection standards?
a. Nonlinear-nonthreshold effect
b. Linear-nonthreshold effect
c. Linear-threshold effect
d. Nonlinear-threshold effect - Which of the following means there is no safe level of radiation and the response to the radiation is not directly proportional to the dose received?
a. Nonlinear-nonthreshold effect
b. Linear-nonthreshold effect
c. Linear-threshold effect
d. Nonlinear-threshold effect
A
- D. The effects mentioned in choices A and B are
graphically demonstrated on dose-response curves. - B. It is assumed that for every dose of radiation there
is some response in the organism. This does not mean
there is damage, just a response. - A
12
Q
- Which of the following means there is no safe level of
radiation and the response to the radiation is directly proportional to the dose received?
a. Nonlinear-nonthreshold effect
b. Linear-nonthreshold effect
c. Linear-threshold effect
d. Nonlinear-threshold effect - Which of the following means there is a safe level of radiation for certain effects and those effects are directly proportional to the dose received when the safe level is exceeded?
a. Nonlinear-nonthreshold effect
b. Linear-nonthreshold effect
c. Linear-threshold effect
d. Nonlinear-threshold effect - Which of the following means there is a safe level of radiation for certain effects and those effects are not directly proportional to the dose received when the safe level is exceeded?
a. Nonlinear-nonthreshold effect
b. Linear-nonthreshold effect
c. Linear-threshold effect
d. Nonlinear-threshold effect
A
- B.
- C.
- D
13
Q
- Effects of radiation where the probability of occurrence, not severity of occurrence, is proportional to the dose are called:
a. Stochastic effects b. Deterministic effects
c. Genetic effects d. Somatic effects - Effects of radiation that become more severe as dose
increases are called:
a. Dose-response curves b. Deterministic effects
c. Genetic effects d. Somatic effects - According to NCRP Report #116, what is the embryo or fetus equivalent dose limit per month?
a. 0.5 mSv b. 0.1 mSv c. 5 mSv d. 0.05 mSv
A
- A. Increased dose equals increased probability of
effects, although it does not increase severity of effects. - B. Deterministic effects have threshold doses below
which the effects do not occur. - A. Note the answer is in millisievert.
14
Q
- According to NCRP Report #116, the occupational cumulative effective dose limit = age in years × what dose?
a. 5 mSv b. 0.1 mSv c. 0.5 mSv d. 10 mSv - According to NCRP Report #116, the annual occupational effective dose limit is:
a. 50 mSv b. 10 mSv c. 0.50 mSv d. 0.05 mSv - According to NCRP Report #116, what is the annual effective dose limit radiography students older than age 18?
a. 50 mSv b. 10 mSv c. 0.50 mSv d. 0.05 mSv
A
- D. For example, a 29-year-old radiographer could
have a cumulative exposure of 29 mSv. - A. This is the dose to remember when you are asked
about radiographers’ annual exposure limit. - A. The same as radiographers’ annual exposure limit.
15
Q
- According to NCRP Report #116, what is the annual effective dose limit for the general public, assuming infrequent exposure?
a. 5 mSv b. 0.1 mSv c. 10 mSv d. 0.05 mSv - According to NCRP Report #116, what is the embryo
or fetus equivalent dose limit for gestation?
a. 5 mSv b. 10 mSv c. 0.5 mSv d. 0.05 mSv - According to NCRP Report #116, what is the annual
effective dose limit for the general public, assuming frequent exposure?
a. 5 mSv b. 1.0 mSv c. 0.5 mSv d. 0.05 mSv
A
- A.
- A. This is the same as the annual general public dose
for infrequent exposure. - B.
16
Q
- According to NCRP Report #116, what is the annual effective occupational dose limit for the lens of the eye?
a. 1.5 mSv b. 1.0 mSv c. 100 mSv d. 150 mSv - The WR used in calculating sievert takes into account
which of the following?
a. Meiosis b. Age. c. LET d. Pregnancy - LET and biological damage are:
a. Directly proportional b. Indirectly proportional
c. Inversely proportional d. Unrelated
A
- D. Be sure to master all of the effective dose limits
for occupational exposure and exposure of the general
public. - C. The radiation weighting factor takes into account
the source of exposure, which may be wave or particulate, and the actual amount of energy deposited per
unit length of tissue—the LET (linear energy transfer). - A. The amount of energy deposited in tissues is
directly responsible for any biologic damage that may
occur.
17
Q
- The ability of different types of radiation to produce the same biological response in an organismis called:
a. LET b. WR. c. RBE d. Doubling dose - The phases of the cellular life cycle, in order, are:
a. Prophase, metaphase, anaphase, telophase
b. Interphase, prophase, metaphase, anaphase, telophase
c. G1, S, G2, telophase
d. Interphase (G1, S, G2), prophase, metaphase, anaphase, telophase - The process of cell division for germ cells is called:
a. Mitosis b. Spermatogenesis c. Organogenesis. d. Meiosis
A
- C. Relative biologic effectiveness.
- D. Remember that the cellular life cycle always begins
with interphase. The reason D is the correct answer is
because the three steps in interphase are listed in their
proper order. This makes choice D a better answer
than choice B. - D. Choice A defines cell division for somatic cells
only
18
Q
- Which of the following occurs when radiation transfers its energy to DNA?
a. Indirect effect. b. Target theory.
c. Direct effect. d. Mutations - Which of the following states that each cell has a master molecule that directs all cellular activities and that, if inactivated, results in cellular death?
a. Indirect effect. b. Target theory
c. Direct effect. d. Mutations - Which of the following describes the amount of radiation required to increase the number of mutations in a population by a factor of 2?
a. Indirect effect b. Target theory
c. Doubling dose d. Mutations
A
- C. The DNA in the cell’s nucleus has been directly
struck by the photons. - B. The master molecule is the DNA in the cell’s nucleus.
- C.
19
Q
- What occurs when radiation transfers its energy to the cellular cytoplasm?
a. Indirect effect b. Target theory
c. Direct effect d. Doubling dose - Which of the following induces radiolysis?
a. Indirect effect b. Target theory
c. Direct effect d. Doubling dose - What is the name for changes in genetic code passed
on to the next generation?
a. Indirect effect b. Target theory
c. Direct effect d. Mutations
A
- A. The energy is deposited in the cytoplasm, causing
radiolysis to occur, which poisons the cell. This indirectly causes the damage to the cell’s nucleus. - A. Radiolysis causes the production of hydrogen peroxide in the cytoplasm, a poison to the cell.
- D. Most radiation-induced mutations are recessive.
20
Q
- Which of the following is responsible for producing
free radicals?
a. Indirect effect. b. Target theory
c. Direct effect d. Doubling dose - What occurs when the master molecule is struck by
radiation?
a. Indirect effect. b. Target theory
c. Direct effect d. Doubling dose - Which of the following poisons the cell with H2O2?
a. Indirect effect b. Target theory
c. Direct effect d. Doubling dose
A
- A. Free radicals are produced as a result of radiolysis.
- C. The master molecule is DNA, located in the cellular nucleus.
- A. This is a result of radiolysis.
21
Q
- Most of the damage to a cell occurs as a result of:
a. Direct effect. b. Mutations
c. Law of Bergonié and Tribondeau d. Indirect effect - Cell radiosensitivity is described by the:
a. Inverse square law. b. Law of Bergonié and Tribondeau
c. Reciprocity law d. Ohm’s law - The law that states that cells are most sensitive to radiation when they are nonspecialized and rapidly dividing is the:
a. Inverse square law. b. Law of Bergonié and Tribondeau
c. Reciprocity law d. Ohm’s law
A
- D. Because the cellular cytoplasm is so much larger
than a cell’s nucleus, it is more likely to be struck by
an incoming x-ray photon. Therefore, statistically
speaking, more damage will occur to cells because of
indirect effect than from the less probable occurrence
of direct effect. - B. The Law of Bergonié and Tribondeau states that
cells are most radiosensitive when they are immature,
undifferentiated, and rapidly dividing. - B. This law describes cell radiosensitivity.
22
Q
- Cells are more radiosensitive when:
a. Fully oxygenated. b. Deoxygenated
c. Slowly dividing d. Near the skin - Blood count can be depressed with a whole-body dose of:
a. 0.25 Sv b. 25 Sv c. 1 Sv d. 10 Sv - The most radiosensitive cells in the body are:
a. Lymphocytes b. Epithelial cells
c. Nerve cells d. Muscle cells
A
- A. This is known as oxygen enhancement ratio (OER).
- A.
- A. The least radiosensitive cells are nerve and muscle
cells.
23
Q
- Cells that are least sensitive to radiation exposure include:
a. Ova and sperm b. Epithelial cells
c. Nerve and muscle cells. d. Blood cells - Compared with ova in younger and older women, ova in women of reproductive age are:
a. More radiosensitive b. Less radiosensitive
c. About the same - Most somatic effects occur:
a. At doses delivered during diagnostic radiography
b. At doses beyond doses used during diagnostic radiography
c. In middle age
d. In old age because of an increase in medical care
A
- C. Epithelial cells are very radiosensitive.
- B. Ova are more radiosensitive in young girls and after
middle age. - B. It is important to remember that most somatic
effects of exposure to ionizing radiation do not occur
at doses used during diagnostic procedures, unless
repeated procedures are performed at high dose levels.
It is always important to practice ALARA.
24
Q
- Somatic effects manifest in:
a. The person who has been irradiated b. The next generation
c. Newborns d. Imaging technologists - Which of the following is considered a late somatic effect?
a. Carcinogenesis. b. Genetic effect
c. Alzheimer disease. d. Parkinson disease - Which of the following is used to limit the area of the patient being irradiated?
a. Grid b. Lead mask
c. Collimator. d. Compensating filter
A
- A. Genetic effects may occur in the next generation as
mutations. - A. Alzheimer disease and Parkinson disease have not
been linked to radiation exposure. - C.
25
Q
- Gonadal shields may reduce exposure to female gonads by up to:
a. 50% b. 95% c. 10% d. 75% - Which of the following sets of exposure factors would result in the lowest dose to the patient?
a. High mAs, low kVp b. Low mAs, high kVp
c. Low mAs, high kVp, small focal spot
d. Low mAs, high kVp, large focal spot - Which of the following is used as part of an effort to practice the ALARA concept?
a. Grids b. Increased mAs
c. Collimation d. Thinner filtration
A
- A. Gonadal shields may reduce exposure to males by
up to 95%. - B. Use of low-mAs, high-kVp techniques always
results in a lower patient dose. Focal-spot size is not
related to patient dose. - C. The other choices all result in increased dose to the
patient
26
Q
- The cardinal rules of radiation protection include:
a. Collimation, gonadal shielding, no repeats
b. Collimation, short exposure time, no repeats
c. Shielding, distance, time
d. Time, distance, collimation - Which of the following is used to survey an area for
radiation detection and measurement?
a. TLD b. Film badge
c. Handheld ionization chamber
d. Geiger-Mueller detector - Which of the following is accurate as low as 100
μGya?
a. TLD. b. Film badge.
c. OSL d. Handheld ionization chamber
A
- C. These are the three basic methods for providing
optimal radiation protection. - C. TLDs and film badges are used for personnel measurement, whereas a Geiger-Mueller detector is used
to detect the location of a specific source of radiation
such as a radionuclide. - B.
27
Q
- Which of the following includes filters for measurement of radiation energy?
a. TLD. b. Film badge
c. OSL d. Handheld ionization chamber - Which of the following may be used to measure in-air
exposures in a fluoroscopic room?
a. TLD b. Film badge
c. Handheld ionization chamber
d. Geiger-Mueller detector - What detection device sounds an alarm to indicate the presence of radioactivity?
a. TLD b. Film badge
c. Pocket ionization chamber d. Geiger-Mueller detector
A
- B. Metal and plastic filters are incorporated into the
film badge case. - C. This is the monitor of choice to be used when surveying radiation dose in a fluoroscopic installation.
The TLD and film badge are used for personal monitoring, and the Geiger-Mueller detector surveys for radioactive particles. - D.
28
Q
- Which of the following is accurate as low as 50 μGya?
a. TLD b. Film badge
c. Pocket ionization chamber
d. Handheld ionization chamber - Which of the following is a digital monitor that may be used to measure dose in an area?
a. TLD b. Film badge
c. Pocket ionization chamber
d. Handheld ionization chamber - Which of the following may be used for 3 months at
a time?
a. TLD b. Film badge
c. Pocket ionization chamber d. Geiger-Mueller detector
A
- A.
- D. The TLD and film badge are not digital and are
used to measure personal dose. - A. The optically stimulated luminescent dosimeter
may also be used up to 3 months.
29
Q
- Which of the following is sensitive to extremes in environment?
a. TLD b. Film badge
c. Pocket ionization chamber
d. Handheld ionization chamber - Which of the following is used to represent the mean
marrow dose?
a. GSD b. ALARA. c. MMD. d. DMM - The radiation dose that would cause the same genetic injury to the population as the sum of doses received by individuals actually being exposed is called:
a. GSD b. ALARA c. MMD d. MPD
A
- B. The film badge is sensitive to extremes in temperature and humidity. It is being phased out of use.
- C. MMD stands for mean marrow dose.
- A. GSD stands for genetically significant dose.
30
Q
- The timer used in fluoroscopy:
a. Must be 3 minutes
b. Should always be reset before the alarm sounds so
that it does not annoy the radiologist
c. Sounds an alarm after 3 minutes
d. Is used to alert the fluoroscopist after 5 minutes of fluoroscopy scanning have elapsed - The most effective protection against radiation exposure for the radiographer is:
a. Lead apron b. Lead gloves
c. Lead glasses d. Distance - If the dose of scatter radiation in fluoroscopy to the radiographer is 10 mGya at a distance of 2 feet from the table, where should the radiographer stand to reduce the dose to 2.5 mGya?
a. 8 feet from the table b. 4 feet from the table
c. At the foot of the table. d. Directly behind the fluoroscopist
A
- D. Choice A is incorrect because the timer must
sound an alarm after 300 seconds (5 minutes). Choice
B is incorrect because the purpose of the alarm is to
sound an alert. Choice C is incorrect because the
alarm sounds after 5 minutes. - D. This is one of the three cardinal principles of radiation protection; the others are time and shielding.
- B. This problem is different from many you have been
asked: you are being given the new dose and asked
to figure out what the new distance should be. You
should not need to use an equation on paper or a calculator to solve this problem. The question wants you
to reduce your dose to ¼ the amount you receive at a
distance of 2 feet. Keeping in mind the inverse square
law, you may recall that doubling distance causes the
dose to drop to ¼. Therefore the correct answer would
be to step back to a distance of 4 feet from the table.
Choice A implies that you need to quadruple your distance from the table to reduce the dose to ¼. Choice
D would result in a decrease in dose because of shielding but not the specific reduction in dose mentioned
in the problem.
31
Q
- Lead aprons used in fluoroscopy must be at least:
a. 0.5-mm lead b. 0.25-mm lead
c. 0.1-mm lead d. 0.25-mm lead equivalent - Which of the following is true concerning holding of
patients for radiographic exams?
a. May be performed routinely to obtain a diagnostic
exam
b. Should be done only when absolutely necessary,
and then the holding should be done by a competent radiographer so that a repeat will not be
needed
c. Should be done only when absolutely necessary,
and then the holding should be done by a nonpregnant member of the patient’s family
d. May be performed using a student radiographer to
hold because students are not exposed as often as
staff radiographers - The factors that must be considered in the design of
structural shielding for a radiology room or department include:
a. Use, occupancy, workload
b. Time, distance, shielding
c. Occupational and nonoccupational exposure
d. Number of employees and number of students
A
- D. This thickness is the minimum that must be worn;
0.5-mm lead equivalent should be worn. This is tricky
and is used here to make the point that careful reading
of the question is very important. - C. Choice A is incorrect because holding patients
should never be routine. Choice B is incorrect because
a radiographer should be the last choice to hold the
patient. Choice D is incorrect because routinely using
student radiographers is unacceptable in practice. - A.
32
Q
- The lowest intensity of scatter radiation from the patient is located:
a. At the head of the table
b. At a 90-degree angle from the patient
c. At a 180-degree angle from the patient
d. At the foot of the table - Minimal (M) readings on dosimeter reports mean:
a. A dose below the sensitivity of the dosimeter has
been received
b. A maximum dose has been received
c. A mean (average) dose has been received
d. Much radiation has been received - A readout on the fluoroscopic monitor that indicates
air kerma striking the surface of the patient is:
a. mA meter b. DAP meter
c. ESD meter d. kVp meter
A
- B. Hence this is the best place to stand whenever possible, when necessary.
- A.
- B. Dose area product meter
33
Q
- Which of the following is the most sensitive personnel monitoring device?
a. TLD b. Film badge.
c. OSL dosimeter. d. Geiger-Mueller detector - Minimum source-to-skin distance for mobile radiography must be:
a. 15 inches b. 12 inches c. 36 inches d. 55 inches - Positive beam limitation is also known as:
a. Use of collimators. b. Beam limitation used for all exams
c. Use of beam restrictors. d. Automatic collimation - Added tube filtration should be adjusted by the radiographer:
a. To “harden” the x-ray beam
b. To remove the soft rays from the x-ray beam
c. To exercise radiation protection
d. Never
A
- C. The OSL dosimeter is most sensitive, followed by
the TLD and film badge. - B.
- D. It is also known by its abbreviation of PBL.
- D. Choices A, B, and C are all reasons filtration is
used; however, filtration should never be adjusted
by the radiographer. A qualified radiation physicist
should be the only person adjusting x-ray beam
filtration.
