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Comprehensive Personnel Monitoring in Radiation Control

This course provides an overview of personnel monitoring focusing on regulations, exposure limits, internal and external monitoring methods, dose calculations, and reporting. Understand dose terms, regulatory compliance, dosimetry devices, and actions for abnormal situations. Gain knowledge of internal dosimetry, biological risks, and radiation dose units. Learn about exposure limits and monitoring requirements for various situations.

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Comprehensive Personnel Monitoring in Radiation Control

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  1. Personnel Monitoring ACADs (08-006) Covered Keywords Description Supporting Material

  2. PersonnelMonitoring HTP001.012

  3. Course Overview • Introduction • Terms & Definitions • Regulations, Exposure Limits & Guidelines • External Exposure Monitoring • Internal Exposure Monitoring • Dose Terms & Dose Calculations • Dose Tracking & Reporting

  4. Enabling Objectives: 1 • Identify Dose Terms • State Regulations & Limits • Familiar with Radiation Monitoring Devices • Describe Operation of Various Dosimeters • Explain Dosimetry Administrative Controls • Use of Multiple & Extremity Dosimeters • Dosimetry for Various Situations

  5. Enabling Objectives: 2 • Describe Actions for Abnormal Situations • Explain Concepts of Internal Dosimetry • Primary Radionuclides of Concern • Describe Biological Effects & Risks • Explain Dose Calculation Methods • Assessment of Radioactivity Uptake • Dose Tracking and Reporting

  6. Units of Radiation Dose:Absorbed Dose • Gray – The SI Unit of Absorbed Dose1 Gray = 1 Joule/Kilogram (1 gray = 100 rads) • Rad – The Special Unit of Absorbed Dose1 rad = 100 ergs/gram or 0.01 Joule/kg (1 rad = 0.01 gray)

  7. Units of Radiation Dose:Dose Equivalent • Rem – The Special Unit of Any Quantities expressed as Dose Equivalent (DE)DE = Absorbed Dose times Quality Factor(1 rem = 0.01 sievert) • Sievert (Sv) – The SI Unit of Quantities expressed as Dose Equivalent (DE)(1 Sv = 100 rems)

  8. Quality Factors Type of RadiationQuality FactorX-Rays, γ, or β 1Alpha, FissionFragments, etc. 20Neutrons (Unknown Energy) 10High-Energy Protons 10

  9. Personnel Monitoring:Required by 10CFR20.1501

  10. Purposesfor Monitoring • Regulations Comply with • Evaluate: - Magnitude & Extent of Radiation Levels - Quantities of Radioactive Materials - Potential Radiological Hazards

  11. Conditions Requiring External Monitoring • Dose > 10% of 10CFR20.1201 Limits • DDE > 0.1 rem (1 mSv) for Minors • LDE > 0.15 rem (1.5 mSv) for Minors • SDE/Extremity Dose > 0.5 rem for Minors • DDE > 0.1 rem (1 mSv) During Pregnancy • Entering High or Very High Radiation Area

  12. Conditions Requiring Monitoring for Internal Exposures • Greater than 10% of Applicable ALI • CEDE > 0.1 rem (1 mSv) for Minors • CEDE > 0.1 rem (1 mSv) During Pregnancy

  13. Exposure Limits & Guidelines • TEDE </= 5 rems (0.05 Sv), or DDE + CDE </= 50 rem (0.5 Sv) • LDE </= 15 rem (0.15 Sv) • SDE/Extremity </= 50 rem (0.5 Sv) • DE </= 0.5 rem (5 mSv) to Embryo/Fetus • TVA Administrative Limit: TEDE </= 1 rem (0.01 Sv)

  14. Planned Special Exposures (PSE) Conditions: - Authorized in Writing Before Exposure Occurs - Individuals Informed of Purpose - Individuals Informed of Doses- Individuals Instructed in Measures to Keep Doses ALARA

  15. Emergency Dose Limits Voluntary Only Individuals Informed of Risk - 10 Rem TEDE to Prevent: Serious Damage to the Plant Serious Hazard to Personnel - 25 Rem TEDE to Save a Life

  16. Exposure to Pregnant Women • DDE </= 0.5 rem (5 mSv) to Embryo/Fetus • Copy of Regulatory Guide 8.13 • No Airborne or Contaminated Areas • Initial Whole Body Count Performed

  17. Modes of Exposure • External Exposure • Internal Exposure • Combination of the Two

  18. External Exposure Monitoring • Whole Body TLDs • Multiple Partial Body TLDs • Extremity TLDs • Whole Body DRDs • Dose Rate Measurements

  19. Thermoluminescence • Thermo – Hot • Luminescent - Light

  20. Electron Trapping

  21. TLDs • Li2B4O7:Cu and • CuSO4:Tm

  22. Li2B4O7:Cu TLD • Wide Range (10 mR to 100,000R) • Long Data Retention (Low Fading) • Linear Response • Sensitive to β, γ, X-Rays, and Neutrons • Reusable and Economical • Not Susceptible to Radiofrequency Interference

  23. Lithium Borate Response Curves Radiation Response per Roentgen 2 Element 1 1 0 2 Element 2 1 0 0.01 0.1 1 10 Photon Energy (MeV) Phoon

  24. CuSO4:Tm TLDs • Range: 1 mR to 1,000 R • Linear up to about 200 R • Sensitive to β, γ, and X-Rays • Over responds to Low Energy X-Rays • Useful for Environmental Measurements

  25. Calcium SulfateResponse Curves Radiation Response per Roentgen 10 Element 3 5 0 2 Element 4 1 0 0.01 0.1 1 10 Photon Energy (MeV) Phoon

  26. Limitations of Both Types • Sensitive to Heat, Moisture, and Shock • Can be Shielded by the Body • Subject to Improper Wear by Workers • Misuse Results in Incorrect Data • Errors from Logistical/Recordkeeping

  27. Panasonic TLDs

  28. Thermoluminescent Dosimeter

  29. TLD Badge Assembly

  30. TLD Badge

  31. Panasonic 802 TLD Element #TLD MaterialFiltration 1 Li2B4O7:Cu 14 mg/cm2 2 Li2B4O7:Cu 160 mg/cm2 3 CuSO4:Tm 160 mg/cm2 4 CuSO4:Tm 0.7 mg Lead

  32. Measuring Neutrons with TLDs • Use 6Li and 10B Rather Than 7Li and 11B • Fast Neutrons not Directly Measured • Neutrons Moderated by the Body • Slower Recoil Neutrons Measured • “Albedo Effect”

  33. Panasonic 802 TLD Element #TLD MaterialFiltration 1 Li2B4O7:Cu 14 mg/cm2 2 Li2B4O7:Cu 160 mg/cm2 3 CuSO4:Tm 160 mg/cm2 4 CuSO4:Tm 0.7 mg Lead

  34. Reading Panasonic TLDs

  35. System Calibration • Routine Calibration • Daily QC Check • Calibration TLDs • On-Line QC TLDs Daily

  36. System QC/QA • TEDS Accredited by NIST and NVLAP • Intercomparison Tests • Review & Verification Checks • Statistical Review Technology • Assessed by External Organizations • Quality Manager Assessment • Routine Internal Evaluations

  37. Badge Issue & Collection • Issued & Collected by RADCON • Computer Assigns a TLD Number • Issued for a 3-Month Period • Processed by TEDS • Background TLDs Maintained

  38. Special Pulls • Administrative Dose Limits Exceeded • DRD Off Scale or Displays Error • Termination/Relocation of Employee • Quality Control Check • Multiple Badge or Neutron Processing

  39. Wearing the TLD • Front of Body, Neck to Waist • Conditions May Require Change • Wear Inside Coveralls in Contaminated Area • Do Not Open or Pamper With the Badge

  40. Proper Wearing of Dosimetry

  41. Multiple Badging • Nonuniform Radiation Field • Whole Body Dose >/= 100 mrem/h & Variable • Highest Dose Location Unknown • Radiation Levels Unknown and Gradient Nonuniform

  42. Multi-Badge Placement • Forehead • Chest • Back • Gonads • Right Arm • Left Arm • Right Femur • Left Femur • Control (Not Worn)

  43. Extremity Badges • >/= 500 mrem to Extremity • Handling Unshielded Beta Sources • Whole Body (Except Hands) Shielded • Handling Small Non-Shielded γ Sources • Decontamination of Beta • Glove Box Operations • Handling I-125

  44. Extremity Dosimeter

  45. Wearing Extremity Badge

  46. Secondary Dosimetry • In Any RCA • Includes: - EDs -DADs • Read Periodically During Job Assignment • Wear on Front of Person • Wear Inside in Contamination Area

  47. Electronic Dosimeter

  48. Electronic Dosimeter Display

  49. Pocket Chamber

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