Ch. 3 Safety Flashcards
(80 cards)
Radiation that possesses the ability to remove electrons from atoms by a process called ionization
Ionizing radiation
Effects of radiation on the body being irradiated
Somatic effects
Effects of radiation on the genetic code of a cell; affects the next generation
Genetic effects
Radiation contained in the unpolluted environment
Natural background radiation
Also called man-made radiation (medical x-rays)
Artificially produced radiation
Radiation exiting the x-ray tube
Primary radiation
X-rays that emerge from the patient and strike the image receptor
Exit radiation (remnant radiation or image-producing radiation)
Absorption and scatter (loss of intensity) of the x-ray beam as it passes through the patient
Attenuation
X-ray beam that contains photons of many different energies
Heterogeneous beam
Absorption of x-ray photons in the atoms of the body
Photoelectric effect
Organization that publishes radiation protection guidelines for the United States
National Council on Radiation Protection and Measurements (NCRP)
Scatter of x-ray photons from the atoms of the body
Compton effect
Unit of exposure
Air kerma
Unit of absorbed dose, measured in joules per kilogram (J/kg), 1 Gy = 1 J/kg
Gray
Unit of radiation absorbed in air
Gray a
Upper boundary dose that can be absorbed, either in a single exposure or annually, with a negligible risk of somatic or genetic damage to the individual; effective dose implies whole-body radiation exposure
Effective dose limit
Unit of radiation absorbed in tissue
Gray t
Unit of effective dose and equivalent dose
Sievert
Lifetime occupational exposure must not exceed the radiographer’s age multiplied by 10 mSv
Cumulative effective dose
Equal to the effective dose multiplied by the radiation weighting factor
Equivalent dose
Concept of radiologic practice that encourages radiation users to adopt measures that keep the dose to the patient and themselves at minimal levels
As low as reasonably achievable (ALARA)
Graphs that illustrate the relationship between radiation dose and the response of the organism to exposure; may be linear or nonlinear, threshold or nonthreshold
Dose-response curves
Randomly occurring effects of radiation; the probability of such effects is proportional to the dose (increased dose equals increased probability, not severity, of effects)
Stochastic (probabilistic) effects
Effects of radiation that become more severe at high levels of radiation exposure and do not occur below a certain threshold dose
Tissue reactions (deterministic)