Quiz #1 -Radiation Protection (Chapters 1 & 2)
Define milligray
A subunit of gray Equal to one one-thousandth of a gray
What organization was founded in 2007 that continues their pursuit to raise awareness of the need for dose reduction protocols by promoting pediatric-specified scan protocols to be used for both radiology and nonradiology users of CT?
Alliance for Radiation Safety in Pediatric Imaging.
What is equivalent dose?
Amount of energy absorbed by humans Measured in millisievert
Why should the selection of technical exposure factors for all medical imaging procedures always follow ALARA?
Because radiation-induced cancer does not appear to have a dose level below which individuals would have no chance of developing this disease.
Define ionizing radiation
Conversion of atoms to ions Makes tissues valuable for creating images Radiation dose
What is exposure measured in?
Coulomb per kilogram-SI unit Milliroentgen
Which of the following provides the basis for determining whether an imaging procedure or practice is justified?
Diagnostic efficacy
What are the 2 largest sources of artificial radiation?
Diagnostic x-ray and Nuclear medicine
Which of the following radiation quantities is intended to be the best overall measure of the biologic effects of ionizing radiation?
Effective dose
Define Alpha particles
Emitted from nuclei of very heavy elements during the process of radioactive decay Each contains 2 protons and 2 neutrons Approximately four times the mass of a hydrogen atom and a positive charge twice that of an electron Lose energy quickly
What is particulate radiation?
Form of radiation that includes alpha particles, beta particles, neutrons, and protons They possess sufficient kinetic energy to be capable of causing ionization by direct atomic collision High speeds
As frequency increases, penatration
Increases
What can ionizing radiation cause?
Injury in normal biological tissue
Define Beta particles
Inside nucleus Identical to high-speed electrons except for their origin
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
What 2 parts is the electromagnetic spectrum divided into?
Ionizing radiation and Non-ionizing radiation
Define Background equivalent radiation time (BERT)
Method to compare the amount of radiation received from a radiologic procedure with natural background radiation
What are examples of Non-ionizing radiation?
Microwaves and radio waves
What is absorbed dose measured in?
Milligray
How is effective dose measured?
Millisievert
Define ionizing radiation
Radiation that produces positively and negatively charged particles when passing through matter
In a hospital setting, which of the following professionals is expressly charged by the hospital administration with being directly responsible for the execution, enforcement, and maintenance of the ALARA program?
Radiation Safety Officer
Define Coulomb per kilo
SI unit for radiation exposure
Define effective dose
Takes into account the dose from all types of ionizing radiation
Define absorbed dose
The amount of energy per unit mass absorbed by an irradiated object
What is absorbed dose?
The amount of kinetic energy per until mass that has been absorbed in a material Measured in milligray
What is Effective dose?
The dose for all types of radiation Measured in millisievert
Define exposure
The total electric charge of one sign (all + or -)
What are examples of ionizing radiation?
X-ray, gamma rays
Electromagnetic waves are characterized by their:
frequency and wavelength
The degree to which a diagnostic study accurately reveals the presence or absence of disease in the patient
diagnostic efficacy
The quantity that is used for radiation protection that provides a measure of overall risk of exposure to humans from ionizing radiation.
effective dose
Typically, people are more willing to accept a risk if they perceive that the potential benefit to be obtained is:
greater than the risk involved.
X-rays are a form of which of the following kinds of radiation?
ionizing
Define radiation
kinetic energy that passes from one location to another
Define energy
the ability to do work
Define electromagnetic spectrum
the range of wavelengths or frequencies over which electromagnetic radiation extends.
