LSU Radiation Safety

Card Set Information

LSU Radiation Safety
2015-01-21 12:09:06
Radiation safety

LSU Radiation Safety
Show Answers:

  1. Which particles have mass & volume?
    • Alpha
    • Beta
    • Neutrons
  2. Alpha particle
    • has + charge
    • has mass
    • very easy to shield; a sheet of paper will stop alpha
    • if alpha is next to live tissue it can traverse 6-10 cell layers
    • It give up its energy in a very short distance.
    • This fact in part the reason that alpha has a quality factor of 20
  3. Beta particle
    • Has a - charge
    • has mass
  4. Uncharged types of radiation
    • photon
    • neutron
  5. Ionizing
    Has enough energy to completely remove an electron from an atom
  6. MeV and meV
    multiples and submultiples of the electron volt unit referring to 1,000,000 eV and 0.001 eV, respectively.
  7. Gray (Gy)
    SI unit of absorbed dose
  8. rad
    traditional unit of absorbed dose
  9. sievert (Sv)
    • SI unit of dose equivalent
    • 100 rem = 1 Sv
  10. Deep Dose Equivalent (Hd)
    • The dose equivalent at a tissue depth of 1 cm due to external radiation
    • usually only penetrating radiation like x-ray or gamma
  11. Eye Dose Equivalent (Heye)
    The dose equivalent at a tissue depth of 0.3 cm due to external radiation
  12. Shallow Dose Equivalent (H5)
    • The dose equivalent at a tissue depth of 0.007 cm due to external radiation
    • x-ray and gamma plus beta
  13. Committed Dose Equivalent (HT50)
    The dose equivalent received by a tissue (T) over the next 50 years due to an intake of radioactive material
  14. Committed Effective Dose
    • Committed Equivalent (CEDE or HE50) – The sum of the products of the committed dose equivalent to a tissue and a weighting factor for that tissue
    • HE50 = SwT HT50
  15. Approval Letter will include
    • Lists Approved Isotopes
    • Lists Maximum Activity of Each Isotope That Can Be Ordered
    • Lists Maximum Activity Of Each Isotope That May Be In The Laboratory
    • Lists Approved Laboratory Locations
  16. What is Provided?
    • Contamination and/or other radiological surveys
    • Radiation badges, if applicable
    • Waste pick up and storage of short lived waste
    • Assure compliance with regulations
  17. What Is Not Covered?
    • Maintenance fee charged by the state on x-ray machines
    • Disposal of long lived radioactive waste
  18. How frequent does Radiation Safety Office survey each laboratory where radioactive material is used or stored?
    • every 3 months
    • must be no more than 100pCi/100 square cm
  19. What is required every time 0.5 mCi of a radioactive material is handled by a worker in the lab?
    In-Lab surveys which must be kept and documented in the labs copy of the Radiation Safety Manual in the appropriate section
  20. What is included in the Laboratory Audits where
    radioactive material is used or stored?
    • Every 6 months
    • Inventory logs must be up-to-date
    • In laboratory surveys must be recorded
    • Instruments must be calibrated and operating properly
    • Warning and emergency signs must be posted
    • In-laboratory training must be up-to-date
  21. Common Violations
    • Eating and drinking in laboratories
    • Leaving radiation-producing equipment and/or radioactive material unsecured
    • Failure to follow proper waste procedures
    • Failure to conduct and record In Laboratory surveys
    • Failure to maintain source inventory forms
    • Failure to wear appropriate dosimeters
  22. Consequence of violation
    • Initial Violation: Principal investigator will be placed on probation for one year in accordance with PS-99
    • Violations while on Probation: Principal investigator will lose privileges to use radioactive material and/or sources of radiation
  23. Chain of Events for Direct Action
    • Incident particle or photon
    • Excitation or Ionization
    • Dissociation of a molecule due to the excitation or ionization on one of the molecules atoms
    • Possible biological effects depending on the molecule dissociated
  24. Direct Action
    A break in the DNA molecule due to direct action from the radiation or from an electron that it frees from an atom.
  25. Chain of Events for Indirect Action
    • Incident Particle or Photon
    • Ionization of Water Molecule
    • Dissociation of Water Molecule
    • Free Radicals Produced
    • Chemical Changes
    • Possible Biological Effects
  26. Stochastic Effects
    • Are random effects
    • Occur by chance
    • Occur in both exposed and unexposed individuals
    • Are not unequivocally related to radiation exposure
    • Become more likely as dose increases Severity is independent of the dose
  27. Linear No Threshold Model
    • Assumes that any amount of radiation has a detrimental effect
    • Is not a predictive model
    • Is used to establish regulatory dose limits (NRC)
  28. Cancer
    • A stochastic effect
    • Radiation induced tumors are most frequent in the hemopoietic system, thyroid, and skin.
    • Cancer induction is well documented at doses of 100 rad or more
    • Induction at lower doses is inconclusive (possible exceptions are leukemia and thyroid cancer)
    • Tumor induction has a latent time of 5-20 years
    • Radiation induced leukemia in Atomic bomb survivors has been documented at doses above 40 rad
    • Bone Cancer induction has been documented in laboratory animals for large injection of “bone seeking” radionuclide
    • Radiation induced lung cancer is seen mainly in underground miners exposed to high Radon concentrations
  29. Mental Retardation
    • A stochastic effect
    • Most pronounced in those exposed between the 8th and 17th week of pregnancy
    • Brain cells divide rapidly during this period
    • Has been observed in children exposed in-utero to radiation from the atomic bombs in Japan
  30. Genetic Effects
    • A stochastic effect
    • No radiation induced genetic effects have been observed in humans
    • Genetic effects have been observed in animal studies
  31. Non-stochastic / Deterministic Effects
    • A certain minimum dose must be exceeded before the effect occurs
    • The severity of the effect increases as dose increase
    • There is a clear causal relationship between exposure and occurrence
  32. Nonlinear Threshold Response
    • No response is seen until the threshold dose is exceeded
    • At some dose, all individuals experience the effect
    • Applies to non-stochastic effects
  33. List of Non-stochastic Effects
    • Sterility
    • Cataracts
    • Skin Erythema
    • Hemopoietic Syndrome
    • Gastrointestinal (GI) Syndrome
    • Central Nervous System Syndrome
  34. Sterility
    • Temporary sterility had been observed:
    • In men at doses as low as 30 rads
    • In women at doses as low as 300 rads
    • The higher the dose the longer the the period of sterility
  35. Cataracts
    • Threshold eye dose of about 200 rads of beta or gamma radiation
    • Threshold may be as low as 60 rads for neutron radiation
    • Long latent period
  36. Erythema & Other Skin Effects
    • Reddening of the skin (erythema) occurs at photon or beta doses of about 300 rads
    • Higher does may cause epilation, blistering, necrosis, and ulceration
  37. Hemopoietic Syndrome
    • Blood changes may be seen at doses as low as 14 rads
    • Blood changes are almost certain at doses above 50 rads
    • Appears at about 200 rads
    • Characterized by depression or ablation of the bone marrow
    • May be accompanied by nausea, vomiting, fatigue, and increased temperature
    • Death occurs within 1-2 months unless medical treatment is successful
  38. Gastrointestinal Syndrome
    • Occurs at a whole body dose of 1000 rads or greater
    • Characterized by the destruction of the intestinal epithelium and complete destruction of the bone marrow
    • Accompanied by severe nausea, vomiting, and diarrhea soon after exposure
    • Death occurs within a few weeks
  39. Central Nervous System Syndrome
    • Occurs at whole body doses of 2000 rads or more
    • Damages the central nervous system as well as all other organs and systems
    • Unconsciousness occurs within minutes
    • Death follows in a matter of a few hours to a few days
  40. What Needs to be Regulated ?
    • Byproduct Material
    • Source Material
    • Special Nuclear Material
    • Naturally occurring and Accelerator produced Radioactive Material (NARM)
    • Ionizing Radiation Producing Devices
  41. Source Material
    Uranium or thorium or any combination of uranium and thorium in any physical or chemical form
  42. Special Nuclear Material
    Plutonium, uranium-233, uranium enriched in the isotope 233 or in the isotope 235.
  43. NARM
    Naturally occurring or accelerator- produced radioactive material, such as radium, and not classified as source material.
  44. Ionizing Producing Devices
    • Electronic devices that are capable of emitting ionizing radiation.
    • Examples are linear accelerators, cyclotrons, radiofrequency generators that use cyclotrons or magnetrons, and other electron tubes that produce x-rays.
  45. Hierarchy of Standards
    • Federal Laws and Regulations
    • State Laws and Regulations
    • Accreditation Standards
    • National and International Consensus Standards and Guidance
  46. LA Environmental Code PART XV
    • The state of LA, not the NRC, regulates the use of radiation at LSU.
    • Louisiana Radiation Protection Division of the Department of Environmental Quality is the proponent.
    • The LARPD issues specific licenses for the receipt, possession, distribution, use, transportation, transfer, and disposal of radioactive material.
  47. NRC
    • Nuclear Regulatory Commission
    • It governs the use of special nuclear material in excess of 200 grams
  48. Title 29 CFR
    • Occupational Safety and Health Administration (OSHA) is the proponent.
    • Governs the use of all ionizing radiation to include alpha rays, beta rays, gamma rays, X-rays, neutrons, high-speed electrons, high speed protons, and other atomic particles.
    • Part 1910.1096, Ionizing Radiation, includes requirements for dose limits, instructions to employees, posting requirements, and reports of over-exposure.
    • Memorandum of understanding with Nuclear Regulatory Commission.
  49. Title 49 CFR
    Transportation of Radioactive Materials
  50. Radiation Protection Goals
    • Limit probability of radiation bioeffects
    • Develop acceptable risk with derived benefits
    • Protect human kind and its environment
  51. Prevention Of Non-Stochastic Disease
    • Severity varies with magnitude of dose
    • Health effects have a threshold dose
    • Examples: Cataracts, impairment of fertility
  52. Prevention Of Non-Stochastic Disease
    • Severity varies with magnitude of dose
    • Health effects have a threshold dose
    • Examples: Cataracts, impairment of fertility
  53. ALARA
    As Low As Reasonably Achievable
  54. Meaning of Dose
    Exposure x Time = Dose
  55. Ways to reduce exposure
    • increase distance
    • put something in between you and the source
  56. Personnel Monitoring Program
    A systematic process for monitoring, recording, evaluating, and reporting the radiation doses received by occupationally exposed individuals
  57. Moonlighting
    Individuals who incur additional radiation exposure from off-duty employment must provide records of any doses received to the Radiation Safety Office.
  58. Radiation surveys must be made:
    • annually
    • whenever beam-target or specimen-detector geometry is changed
    • whenever shielding arrangements are altered
    • after maintenance work.
    • All operating personnel must be intimately familiar with the principles of operation, principles of radiation safety, and potential general and specific hazards of their particular machine.
    • Radiation surveys must be made
    • Situations which require interlocks to be temporarily disabled require prior approval of the campus Radiation Safety Officer.
    • All radiation producing equipment must have clearly visible warning lights to indicate when the equipment is generating radiation.
    • Unusual operations or unexpected machine behavior must be reported to the campus Radiation Safety Office immediately