Unit 1 Flashcards
Who was the first American radiation worker to die from radiation-induced cancer on October 2, 1904?
Clarence Madison Dally
Once the x-ray photon exits the x-ray tube, but before it enters the patient:
Primary radiation
The probability of Photoelectric (PE) interaction occurring is increased when:
- There is increased mass density of biologic material
- The use of positive contrast media is used
- A primary photon whose energy is at least 1.022 MeV
1 and 2
There is increased mass density of biologic material
The use of positive contrast media is used
Photoelectric (Absorption)
Inner shell electron gets
ejected (ionized).
Occurs between 23-150 kVp
Which is the best method of measuring the overall risk of ionizing radiation?
Absorbed dose
Equivalent dose
Effective dose
Effective dose
Absorbed dose- amount of energy per unit mass that has been absorbed in a material
Equivalent dose- takes into account the type of ionizing radiation that was absorbed. Includes the different degrees of tissue interaction that could be caused by the different
types of ionizing radiation.
Effective dose- estimate of overall harm that might be produced by a given absorbed dose of radiation in human tissue. It takes into account both the type of radiation and the part of the body irradiated.
Which of the following is a form of radiation that is capable of creating electrically charged particles by removing orbital electrons from the atom of normal matter through which it passes?
Ionizing radiation
Which of the following radiation quantities is intended to be the best overall measure of the biologic effects of ionizing radiation?
Effective dose
Which of the following is another term for coherent scatter?
- Characteristic
- Classical
- Elastic
- Unmodified
2, 3, and 4
Classical
Elastic
Unmodified
Characteristic (Photoelectric absorption)- when an electron gets ejected (ionized) from inner shell, the other electrons move from lower level shells to higher levels. Low energy photon is released from this process and it is easily absorbed from the body.
In a hospital setting, which of the following professionals is expressly charged by the administration to be directly responsible for the execution, enforcement, and maintenance of the ALARA program
Radiation safety officer
Cataract formation, reduced fertility and sterility are classified as:
Late tissue reactions of ionizing radiation
Early tissue reactions of ionizing radiation
Late tissue reactions of ionizing radiation
What is the most common unit of measure of equivalent dose?
Millisevert
Same as effective dose
Permanent inherent filtration is helpful in which ways?
- Hardens the beam
- Removes lower energies of the photon beam
- Keeps fast-moving electrons from escaping the tube
1 and 2
Removes lower energies of the photon beam
Keeps fast-moving electrons from escaping the tube
The main adverse effect of the Chernobyl nuclear power plant accident is:
Thyroid cancer
The millisievert (mSv) is equal to:
1/1000 of a sievert
When the radiographer selects 100 kVp on the x-ray console, the x-ray beam will:
Contain primary photons with a maximum energy of 100 kVp and have an average energy of 35 kVp
The millisievert (mSv) is equal to:
1/1000 of a sievert
The amount of energy per unit mass absorbed by an irradiated object:
Absorbed dose
The electromagnetic spectrum can be divided into which two categories?
Non-ionizing
Ionizing
What is the average dose the US resident receives from background radiation per year?
3.1 mSv
What unit is used to measure radiation exposure in the metric international system of units?
Coulomb per kilogram
Absorbed dose is measured in which unit?
Gy
Exposure: C/kg
Absorbed dose: Gy
Effective dose: mSv
Absorbed dose- amount of energy that is deposited in a material per unit mass of the material.
Effective- a measure of general harm in humans. It takes into account the amount of absorbed dose that is received by a human, type of radiation, and the specific organs or organ systems irradiated.
Coherent scattering is most likely to occur at energy levels less than:
10 KeV
Photoelectric absorption is an interaction of photons encountering electrons in which of the atom’s shell?
Inner
Outer
Inner
Radioactive materials in the Earth’s crust is considered:
Natural
X-rays are a form of which of the following kinds of radiation?
Ionizing
All are particulate radiation except:
Gamma
Alpha
Protons
Beta
Gamma
Particulate radiation- subatomic particles are ejected from the nucleus of atoms at very high speeds. This includes:
Alpha
Beta
Protons
Nuetrons
Which of the following is essentially the sum total of air kerma over the exposed area of the patient’s surface
Dose area product
Which of the following is classified as nonionizing radiation?
Visible light
Radiographic fog is caused by:
Small angle scatter
Which of the following interactions between x-ray photons with matter involve a matter-antimatter annihilation reaction?
Pair Production
An individual receives the following absorbed doses: 0.5 mGy of X-rays (Wr=1), 0.8 mGy of alpha particles (Wr=20), and 0.3 mGy of Fast neutrons (Wr=20). What is the person’s total Equivalent Dose (EqD)?
(Hint: when calculating, round to the nearest 0. 1/ first decimal place)
22.5 mSv
The reduction in the number of primary photons in the x-ray beam through absorption or scatter as it passes through an object is referred to as:
Attenuation
All are included in the cardinal principles of radiation except:
Radiologist
A radiation weighting factor (WR) has been established for each of the following ionizing radiations: X-rays = 1, Fast neutrons = 20, and Thermal neutrons = 5. What is the total Effective dose (ED) for a person receiving the following exposures to the gonads (WT = 0.2): 2 Gy of x-rays, 1.35 Gy of Fast neutrons, and 2.6 Gy of thermal neutrons?
(Hint: when calculating, round to the nearest 0.1/ first decimal place)
8.4 Sv
EFD = D x WR x WT
0.2 Gy equals ___ mGy
200 mGy
Which of the following provides the basis for determining whether an imaging procedure or practice is justified?
Diagnostic efficacy
lonizing radiation can cause biologic damage on which levels in humans?
- Molecular
- Cellular
- Organic
1,2 and 3
Cosmic radiation occurs in which two forms?
- Artificial
- Man-made
- Solar
- Galactic
3 and 4 only
Utilizing the BERT method:
- does not imply radiation risk, it is simply a means for comparison.
- emphasizes that radiation is an innate part of our environment.
- provides an answer that is easy for the patient to comprehend.
1, 2, and 3
According to the Environmental Protection Agency (EPA) which source is the second leading cause of lung cancer in the United States?
Radon
Exposure is measured in which unit?
C/kg
coulomb/kilogram
