Rad Bio Test 11/30

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Rad Bio Test 11/30
2014-01-03 15:47:33
Radiation biology rad bio radiation therapy science

Rad Bio Test 11/30
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  1. The amount of ionization produced by photons in air per unit of mass of air:
    • Exposure
    • 1R = 2.58 x 10-4 C/kg
  2. What are the units of measure for exposure?
    • Roentgen and Coloumb of charge per kilogram of air
    • 1R = 2.58 x 10-4 C/kg
  3. What are the units of measure for absorbed dose?
    • Rad and Gray
    • 1 Gy = 100 rad
    • 1 rad = .01 Gy
  4. What takes in to account the fact that different types of radiation produce different amounts of biologic damage?
    Dose Equivalent

    100 rem = 1 Sv
  5. What are the units of measure for dose equivalent?
    • Rem  and Sievert
    • 100 rem = 1 Sv
  6. What are the units of measure for activity?
    • Curie (Ci) and Becquerel (Bq)
    • 1 Ci = 3.7 x 1010 Bq
  7. The rate at which a radioactive isotope undergoes nuclear decay:
    • Activity
    • 1 Ci = 3.7 x 1010 Bq
  8. The energy absorbed per unit mass of any material:
    Absorbed Dose

    1Gy = 100rad
  9. Effects that have no threshold and for which the probability of occurrence is a function of dose.
  10. Effects for which a threshold exists and for which the severity of the effect increases with dose.
  11. LD50/30
    • 4.5 Gy (450 rads)
    • Lethal Dose 50% of the population / 30 days of the event
  12. A measure of the genetic risk to a population as a whole from exposure to ionizing radiation of some or all members of that population:
    • Genetically Significant Dose (GSD)
    • measured in rem or Sievert
  13. Dose equivalent to the gonads weighted for the age and sex distribution in those members of the irradiated population expected to have offspring.
    • Genetically Significant Dose (GSD)
    • measured in rem or Sievert
  14. ☆What is the formula used to calculate a person's cumulative exposure dose limit?
    ☆10 mSv X age in years
  15. Shielding is measured in terms of:
    Half value layers
  16. The amount of material needed to reduce radiation exposure to half it's original value:
    Half Value Layer
  17. *What is the effective dose equivalent limit for stochastic effects?
    * Effective Dose Equivalent limit for Stochastic Effects:

    50 mSv (5rem)
  18. *What is the dose equivalent limits for tissues & organs such as red bone marrow, breast, lung, gonads, skin & extremities? (nonstochastic effect)
    • Dose Equivalent Limit for Tissues & Organs
    • (Nonstochastic Effects)

    500 mSv (50rem)
  19. *What is the dose equivalent limit for the lens of the eye? (nonstochastic effects)
    Dose Equivalent Limit for Lens of the Eye (Nonstoctastic)

    150 mSv  (15rem)
  20. Public annual effective dose equivalent limit for continuous or frequent exposure:
    1 mSv  (.1 rem)
  21. Public annual effective dose equivalent for infrequent exposure:
    5 mSv  (.5 rem)
  22. What is the total dose equivalent limit for the fetus?
    • Fetus - total
    • 5 mSv ( .5 rem)
  23. What is the dose equivalent in a month for the fetus?
    • Fetus - month
    • 0.5 mSv  (.05 rem)
  24. The NCRP recommends that the annual effective dose equivalent limit for the genreal population be ____ for those frequently exposed and ____ for those infrequently exposed.
    • Frequent: 1 mSv  (.1rem)
    • Infrequent: 5mSv (.5rem)
  25. Regulatory agencies require individuals to be monitored if it is expected that _____ of the effective dose equivalent limit will be exceeded.
  26. What are the three purposes of monitoring radiation doses received by individual radiation workers?
    • 1. It allows the worker to know how much radiation they are receiving.
    • 2. It allows the facility safety officer to determine whether certain areas or workers are receiving more than expected.
    • 3. It provides a permanent record of radiation received.
  27. The overall accuracy of the film badge is approx:
    + 20%
  28. What kinds of personnel monitors are sent out to be read?
    • TLDs and Film badges are sent out to be read.
    • OSLs are sent out to be read but can be re-stimulated numerous times to confirm accuracy.
  29. What kind of personnel monitors use laser light to stimulate rearrangement of electrons trapped in aluminum oxide (Al2O3) when irradiated?
    Optically Stimulated Luminescence (OSL) dosimeters
  30. Are OSL dosimeters more or less sensitive than film badges?
  31. What are the minimum readings of the film badge and the OSL dosimeter?
    OSL minimum reading: 1mrem

    Film badge minimum reading: 10mrem
  32. OSL dosimeters are capable of a precision of ______.
    1 mrem
  33. Luxel dosimeters are used for:
    X-rays, gamma rays, & beta radiation
  34. The ________ dosimeter allows for differentiation of a single exposure or continous exposure over days or weeks.
  35. ______ the distance from the souce reduces the exposure to _____ its original level.
    • Doubling
    • One-Fourth
  36. _______ is the most important method for protection of operators & members of the general public.
  37. The choice of shielding material depends on the:
    Energy of the beam
  38. ________ is the preferred material for superficial units because it is more effective than concrete or steel at stopping photons at low energies at which photoelectric collisions dominate.
  39. All materials _______ ______ equally gram for gram for higher energies at which Compton interactions dominate.
    Attenuate radiation
  40. The number of patients X the amount of radiation for each
    Workload (W)
  41. The fraction of time the beam is aimed at a particular wall:
    Primary Beam Use Factor (U)
  42. The fraction of time an area will be occupied:
    Occupancy Factor (T)
  43. Distance from the source to the occupied area:
    Distance (d)
  44. The limit for the occupied area:
    Effective Dose (P)
  45. All walls (incl the door) are considered primary walls if _____ or _______ is used.
    IMRT or Cyberknife
  46. Areas where the general public are found:
    • Uncontrolled areas
    • ie. waiting rooms, stairs, hallways
  47. For controlled areas, the occupancy factor (T) is always assumed to be _____
    • equal to 1
    • (this implies that a worker is always present)
  48. Caution: High Radiation Area
    1 mSv in 1 hour  (100 mrem 1 hour)
  49. Grave Danger: Very High Radiation Area
    5 Gy in 1 hour  (500 cGy in 1 hour)
  50. "Beam On" warning lights are required on:
    • The control panel
    • At the entrance door
    • The treatment unit itself
  51. The Cobalt 60 unit is required to have an additional warning light on the _____ of the unit that should be illuminated whenever the unit is energized.
  52. Entrance doors to therapy rooms must be equipped with ______ that will shut off the machine if the door is _____ during the treatment.
    • Interlocks
    • Opened
  53. Regulations require that ______ and ______ communication must be maintained with the patient at all times.
    • Visual (closed circuit tv monitors)
    • Audio
  54. High energy therapy units are required to have an independent ______ _______ in the therapy room to alert the therapist to exposure if they enter the room
    Beam-On Monitor
  55. The independent "beam-on" monitor must have a provision for  ________ in the event  of an electrical failure and ________
    be connected to the therapy machine in any way.
    • Battery Operation
    • Must Not
  56. Cobalt decays to:
  57. In case of an emergency, the therapist must be concerned first with the care of the _______.
    the Patient
  58. The video and audio communication systems must be tested _______
    Every Day
  59. Testing of the ________ may cause harm to the treatment unit, so manufacturers recommendations should be followed carefully.
    Emergency off buttons
  60. A license from the NRC (or an agreement state) is required to _______, _____ and ______ live sources.
    • Receive
    • Possess
    • Use
  61. Brachytherapy sources may only be obtained from Facilities or Firms _________ to distribute them.
    Facilities or Firms licensed to distribute them
  62. Sources must be stored in ______ ______ ______ in an area secure from theft or loss .
    • Heavily shielded safes  
    • "pigs"
  63. Before an implant is prepared, a _________ must be completed by the requesting physician and certification must be made that the implant was assembled in accordance with the  _________.
    • Written Directive
    • Directive
  64. Anytime sources are removed or returned, a ____ _____ must be made and a complete ______ performed.
    • Log Entry
    • Inventory
  65. Inventories of brachytherapy sources are required at least _______, even if no sources have been removed from or returned to the safe.
  66. If brachytherapy sources must be transported through a hospital, the route is planned ahead to minimize the:
    • Exposure to other hospital personnel & the general public
    • (ie. avoid the NICU, busy waiting areas)
  67. While ______ in care of the brachytherapy patient should wear a personnel monitor, _________ need to receive radiation safety instructions but are not required to wear a personnel monitor..
    • Nurses
    • Ancillary Staff/Personnel (maintenance, housekeeping)
  68. The entrance door to a brachytherapy patient's room must be posted with a:
    Caution Sign
  69. Visitation for a brachytherapy patient should be limited to:
    20 minutes per visitor per day.
  70. When visiting a brachytherapy patient, visitors must remain behind a line established by the:
    Radiation Safety Officer
  71. The brachytherapy patient has warning signs posted on the patient's _______, _______, and _______ to avoid inadvertant exposure.
    • Wrist
    • Bed
    • Chart
  72. A _________ of all the contents of the patient's room must be completed before they are discharged to ensure that eveything contaminated is accounted for.
    Survey / Inventory
  73. Because it is possible for the material encapsulating the radioactive material in implant sources to sustain damages and leak, brachytherapy sources must be leak tested at intervals:
    Not to exceed 6 month
  74. Leak tests must be performed on cobalt-60 units:
    Every 6 months
  75. ______ sources are NOT to be handled under any circumstances
    HDR sources
  76. A wall that is struck by the useful beam is considered a _______ wall.
    Primary wall
  77. What are the factors that determine the necesary barrier thickness?
    • Workload (w)
    • Primary beam use factor for each wall (u)
    • Occupancy factor (T)
    • Distance (d)
    • Effective dose
  78. A wall that is struck by scatter radiation or leakage radiation:
    a Secondary wall
  79. While pregnant, the therapist should wear:
    • an Extra Monitor 
    • one at the level of the collar and one at the level of her waist as a fetal monitor.
  80. QA of Simulators:
    All are ________ except for_________
    All are +/- 2  except for:

    Monthly Gantry/Collimator Angle Indicators +/-1°
  81. QA of CT Simulators:
    All are ________ except for_________
    All are +/-2 except for:

    Monthly Table Vertical & Longitudinal +/-1
  82. QA of LINACS:
    All are _____ except for:

    (4 items)
    • All are +/-2 except for:
    • 1. Daily Dosimetry X-ray & Electron Output constancy 3%
    • 2. Monthly Dosimetry Electron Beam Flatness Constancy 3%
    • 3. Monthly Dosimetry X-Ray & Electron Symmetry 3%
    • 4. Monthly Gantry/Collimator Angle
    • Indicators 1°