Safety

• Gray is what?


  absorbed dose
• Gray(GYa) is what?


  air kerma
• Gray (GYt) is what?

  absorbed dose in tissue
• what is Sievert (Sv)?


  unit of effective and equivalent dose
• what is unit of radioactivity?

  Becquerel (Bq)
• what is used to define radiation exposure or radiation delivered to a specific point?

  Air kerma
• what unit of measurement of tissue?

  Gyt
• the product of absorbed dose (Gy) times the radiation weighting factor (Wr) is what unit?

  equivalent dose (dose equivalent)
• the amount of energy transferred by ionizing radiation per unit length of tissue traveled?

  Linear energy transfer LET
• what high ionization radiations have high LET?

  alpha and neutrons
• why are alpha and neutrons considered high LET?

  cause more biological damage
• what radiation causes less biological damage?

  gamma rays and x-rays
• what is the measurements for tissue?

  sievert (Sv)
• unit of effective dose?

  estimates the risk present when various tissues are irradiated
• 1 Sv= ?


  1Gy
• to measure the quantity of radioactive ,material is what unit?

  radioactivity- becquerel (Bq)
• x-radiation exposure involves what?

  transfer of energy through photon-tissue interactions.
• to remove electrons from atoms by process is called?

  ionization
• examples of results of ionization in human cells?

  1. unstable atoms
  2. free electros
  3. production of low energy x-rays
  4. formation of new molecules harmful to cell
  5. cell damage can be exhibited as abnormal function
• what are the general types of radiation damage?

  somatic and genetic
• damage to the exposed individual is?

  somatic
• damage to the genetic code of the germ cell contained in the DNA; may be passed to the next generation what is it?

  genetic
• what is radiation is present in the environment?

  natural background
• what is the greatest source of natural background exposure to human?

  radon
• radiation exiting the xray tube is called?

  primary radiation
• x-rays that emerge from the patient and strike the IR, composed of primary and scattered photons?

  exit radiation
• absorption and scatter(loss of intensity) of the xray beam as it passes through the patient?

  Attenuation
• xray beam that contains photons of many different energies?

  heterogeneous beam
• what two primary photon-tissue interactions are significant in diagnostic x-ray procedures?


  photoelectric and compton
• what interaction results in complete absorption of an incoming xray photon?

  Photoelectric effect
• what interaction produces contrast in radiographic image?

  photoelectric
• what interaction results in scattering of the incoming xray photon?

  Compton
• scatter produced by this interaction must be removed from the beam before it strikes the IR?

  compton
• which interaction has a incoming x-ray photon that strikes a loosely bound, outer shell electron?

  compton
• which interaction is completely absorbed?


  photoelectric
• what interaction is produced by low energy xray photon?

  coherent scatter
• what KVP does not affect image?

  less than 70
• what interaction does not occur in radiography?

  pair production
• indicates that no level of radiation can considered completely safe?

  Linear non-threshold
• the degree of response to exposure is directly proportional to the amount of radiation received?

  linear nonthreshold relationship