RAD-171 Ch.8 Radiation Concepts and Equipment

  1. What is the responsibility of the radiographer when producing a diagnostic image while being consistent with the requirements of the examination?
    to make sure each patient recieves the minimal dose of radiation
  2. what is ionizing radiation capable of doing when interacting with matter
    it is capable of creating charged particles when interacting with matter
  3. what sources can ionizing radiation come from
    natural sources and man made
  4. Can ionizing radiation affect tissues and various organs of the body
  5. why can exposure to radiation be bad for you
    the energy posessed by ionizing radiation is capable of displacing atomic electron bonds that hold molecules of matter together resulting in chemical changes, which can lead to harmful effects
  6. what are the two properties of ionizing electromagnetic radiation
    excitation and ionization
  7. what biologic damages are related to ionizing electromagnetic radiation (2)
    and explain them
    • direct interaction - damage to DNA due to ionization
    • indirect interactions - decomposition of water in the cell
  8. what two categories is radiation grouped in
    ionization radiation is grouped as either particulate (particle) or electromagnetic
  9. are x-rays electromagnetic
  10. what energy particles are included in partciulate radiation
    what do they produce
    • high energy electrons, neutrons and protons 
    • they produce ionizations in matter by direct atomic collisions
  11. what two principal types that are associated with radioactive decay (particulate radiation)
    alpha and beta particles
  12. where does uranium come from
    the ground
  13. what does a gamma ray behave as
    an x-ray photon penetrates through the skin
  14. what radiation particle is the least penetrating and easily stopped in tissue
    alpha particle
  15. how many protons and neutrons are in an alpha particle
    2p 2n
  16. what particle does more damage in a small area of tissue, and has the ability to change the dna
    alpha particle
  17. what particle has moderate penetration and is much smaller
    what is its charge
    • beta particles
    • negative (electron)
  18. what ray or particle is the most penetrating and is made up of pure energy
    gamma rays which also penetrate as photons
  19. which particle has no mass allowing it to penetrate more
  20. what particle has the most mass and is the least penetrating
    alpha particles
  21. List the four characteristics of alpha particles
    • 2protons 2 neutrons
    • decaying radioactive material
    • large amount of mass and charge
    • can travel 5 cm in the air
  22. list the characterisitics of the beta particle
    • its electrons are from decaying radioactive material
    • little mass and charge
    • can tracel 10-100 cm in the air
  23. what photon rays are the same but differ in origin
    xrays come from a machine and gamma rays come from a nucleus
  24. what is the process in which electromagnetic radiation occurs
    photolelectric absorption and compton scattering
  25. what the non ionizing types of photons
    visible light infrared microwaves and radio
  26. waves of high frequency have what wavelengths
    short wavelength
  27. waves of low frequency have what wavelength
    long wavelengths
  28. the effects from ionizing radiation are classified into what 2 categories
    genetic (changes DNA) or somatic (effects on skin and tissue)
  29. what are the biological effects influenced by
    • dose recieved
    • rate dose was recieved
    • type of radiation
    • the age at exposure - the younger you are the worse b/c the cells are still fresh and developing
    • sensitivity of cells
    • body part irridaiated
  30. what are the genetic effects on reproductive cells
    defects in offspring
  31. what are some of the somatic effects and skin conditions
    • skin erythema
    • cataracts
    • radiation induced malignancies
  32. what are the different modes of exposure
    external exposure (outside of body) and internal exposure (inhaling, ingesting, beta, alpha and gamma rays)
  33. List some sources of natural ionizing radiation exposure
    • cosmic radiation (space)
    • terrestrial radiation (ground)
    • radionuclides naturally present (both internal and external)
  34. list some sources of ionizing radiation exposure
    • x-rays
    • radiopharmeceuticals
    • consumer products
    • air travel
    • nuclear fuel production
    • fallouts (bombs and explosions)
  35. what quantities and units are elevant to radiation protection
    • exposure
    • absorbed dose
    • equivalent dose
    • effective dose
  36. what is radiolysis
    when there is decomposition of a water cell
  37. what particle is most penetrating
    least penetrating
    most ionizing
    • gamma
    • alpha
    • alpha
  38. what are sensitive cells
    they are cells that are more likely to divide and undergo mitosis
  39. what cells are radiosensitive
    • wbcs, rbcs, thyroid cells, spermegonia, oogenia cells, skin cells
    • because they are constantly dividing to give us more and more
    • we give blood away, our body undergoes mitosis to create more blood
  40. what is the most radioresistant cell in the body
    • cells of CNS b/c they do not regenerate if they are damaged they can repair but we cant make more nerve cells
    • spinal cord
    • muscle cells
  41. List examples of radiosensitive cells (anything that can regenerate itself)
    • skin
    • blood
    • wbc
    • thyroid cells
    • sperm cells
    • these cells are always dividing so they can regenerate which makes them sensitive to radiation
  42. what is skin erythema
    skin reddening
  43. what are radiation induced malignancies
  44. what are the 2 largest man made sources of radiation
    Medical xray (cat scan) and nuclear medicine
  45. what has highest amt of radiation that is a from a natural source
  46. what is the new total annual background per person
    6.25 mSv
  47. what is the measurement of the number of ionizations in a given quantity in a chamber of air
    roentgen (R)
  48. what measurement measures the amt of energy absorbed
    • Traditional/Conventional - RAD(absorbed Dose)
    • SI unit - Gray (Gy)
  49. what is the measurement that measures the type of radiation, weighing factor, the product of the aabsorbed dose and radiation weight
    • T.U. - REM (equivalent dose)
    • SI Unit - Sv
  50. how do we convert the following back and forth:
    RAD - Gy
    REM - Sv
    • divide by 100 from RAD + REM to Gy & Sv
    • multiply from vice versa
  51. what measurement determines how sensitive the sum of the equivalent doses of specific tissue
    Effective Dose (E)
  52. what is a dosimeter
    dose measuring device
  53. What are the two classification os detection and measurement of ionizing radiation
    • field survey instruments
    • personnel monitoring devices
  54. what are the natural sources of natural radiation
    cosmic (space) and terrestrial (ground)
  55. what is BERT
    background equivalent radiation time
  56. what is the BERT for taking a chest xray
    it is compared to living on earth for ten days
  57. what field survey instrument detects spilled radioactivity
    Geiger mueller survey instruments
  58. which field instrument has a gas filled detector betweentwo electrodes and has ionizing radiationion pairs in gas
    GM survey instruments
  59. what particles are GM instruments not so good at picking up
    • x-ray and gamma
    • better at picking up alpha and beta
  60. what detection device emits a light when simulated by ionizing radiation in which the light is converted to an electri signal (commonly used CT scan)
    scintillation detection devices
  61. what instrument meaures in roetngen and is used to evaluate equiment performence leakage radiation and patient exposure
    ionization chamber instruments
  62. Peronnel monitoring devices are given to workers who accumulate how much radiation of the reccomended dose
    1/10 = 5 rem
  63. where should monitoring devices be worn and wear if you only have one
    • one out side the collar
    • and under the shirt at waist level
    • if you have one wear it outside the collar
    • if you are weating a lead apron make sure both, one is under the apron at waist level and the other is collar level outside the apron
  64. what are the five different monitoring devices
    • optically stimulated luminescence OSL
    • thermoluminescent TLD
    • Film badge dosimeter  
    • pocket dosimeter
    • care of personnel monitoring devices
  65. what is the best dosimeter
  66. In an OSL monitor what detects the radiation
    thin layer of aliminum dioxide
  67. in an OSL dosimeter the level of luminiscence is porportional to what? the
    the amt of radiation recieved
  68. In an OSl dosimeter what is the purpose of the filters of copper and tin
    it gives an idea of how strong the radiation you were exposed to
  69. which dosimeter is sensitive to 1mrem
    OSL dosimeters
  70. what is the metal that detects the radiation in a TLD
    what is the purpose of the crystals
    • lithium fluoride crystals
    • the crystals store energy when exposed to radiation
    • but the stored energy is exposed to heat and emits a light poprptional to the amt of radiaition exposed to
  71. what monitoring device is least sensitive and how much
    TLD and 10mrem
  72. the TLD is very sensitive to what other factors
    • environmental factors
    • heat, humifity temp pressure and prolonged exposure to light
  73. what dosimeters are sensitive to environmental factors and not as sensitive as the others
    • TLD and film badge monitors
    • 10 mrem
  74. how is the detector in a film badge detect radiation
    • it has two pieces of film in light tight packet
    • filters provide info on the energy
  75. which dosimeter has a small ionization chamber (measures ionization in air) and has a hairline fiber that moves on an exposure scale
    pocket dosimeters
  76. which dosimeter can be used by anyone and is used for short period puproses i.e. visiting a certain radioactive spill somewhere)
    pocket dosimter looks like a pen
  77. what is downfall of the pocket dosimeters
    it doesnt keep cumulative record of the persons radiation exposure and is then calibrated back to back zero once done
Card Set
RAD-171 Ch.8 Radiation Concepts and Equipment
radiation safety