Safe Care of Radiation Patients Annual Radiation Safety Training Surgery-7 Staff Andrés Sinisterra Assistant Radiation Safety Officer for Medicine
Yet Another Radiation Safety Session Eh… Mes Amis !!!!!! Brought to you by your neighborhood radiation safety professionals Dedicated to the Health, Safety and Welfare of our Community
Yet Another Radiation Safety Session Brought to you by your neighborhood radiation safety professionals Dedicated to the Health, Safety and Welfare of our Community
S taff Safety Protocols P atient Safety Objectives G eneral Safety Principles
Overview Purpose of Radiation Safety Training Basic Radiation Principles Sources of Radiation Exposure Regulatory Compliance Radiobiology and Risk UCHC Requirements
Radiation Vs. Radioactivity Radiation - energy in transit in the form of high speed particles and electromagnetic waves. Ionizing radiation - radiation with enough energy so that during an interaction with an atom, it can remove tightly bound electrons from their orbits, causing the atom to become charged or ionized. Radioactivity - spontaneous transformation of an unstable atom and often results in the emission of radiation. This process is referred to as a transformation, a decay or a disintegration of an atom.
External vs. Internal Radiation Exposure External Exposure – X-rays, Diagnostic Procedures. Internal Deposition – Contamination from nuclear medicine patient undergoing a diagnostic or therapeutic procedure resulting in an ingestion of radioactive materials by the staff.
Radiation Exposure Limits Type of Exposure Type of Exposure Total Effective Dose Equivalent (TEDE) which is the sum of the Deep-Dose Equivalent (for external exposures) and the Committed Effective Dose Equivalent (for internal exposures) for the whole body Sum of the Deep-Dose Equivalent and the Committed Dose Equivalent to any individual organ or tissue other than the lens of the eye Sum of the Deep-Dose Equivalent and the Committed Dose Equivalent to any individual organ or tissue other than the lens of the eye Eye Dose Equivalent (lens of the eye) Shallow Dose Equivalent to the skin or to any extremity Rem Per Year Rem Per Year 5 or 5,000 mrems 50 or 50,000 mrems 15 or 15,000 mrems 50 or 50,000 mrems
Radiation Exposure Limits Whole body; head and trunk; active blood-forming organs; lens of eyes, or gonads. Hands and forearms; feet and ankles. Skin of whole body. 1.2518.757.5 ( 1,250 mrem) (18,750 mrem) (7,500 mrem) Rem Per Calendar Quarter Type of Exposure (State of Connecticut Administrative Regulations Sect. 19-24-5)
Units of Radiation Exposure Roentgen Measure of electrical charge produced in air 1,000 mr = 1R Fluoro @ SSD ~3-10 R/min Measure of energy absorbed, usually in tissue or bone. 200 rad = transient erythema 1 Gray = 100 Rad Rad (Gray)
Units of Radiation Exposure Rem (Sievert) Measure of occupational risk (cancer) from radiation exposure 1,000 mrem = 1 Rem 1 Sievert = 100 Rem 5 Rem/yr maximum limit 1 R = 1 Rad = 1 Rem Diagnostic & Fluoro X-Rays +-20%
Basic Radiation Safety Principles T ime D istance C ontamination Control S hielding
Brachytherapy 137 cs 192 ir 125 I Brachytherapy 137 cs 192 ir 125 I Temporary Implant Interstitial or Intracavitary Sealed – Encapsulated Sources No Contamination Concern Unless Encapsulation is Compromised gamma radiation
Inverse Square Law ( 137 Cs 192 Ir) For a point source, the intensity varies inversely as the square of the distance from the source. gamma radiation 1 cm 10,000 2 cm 2,500 5 cm 400 10 cm 100 20 cm 25
Radiopharmaceutical Therapies 131 I 153 Sm 32 P Unsealed Radioactive Liquid or Radioactive Capsule (IV or PO) Extreme Contamination Concern All Body Fluids Will Be “Contaminated”
Nuclear Medicine Diagnostic Procedures Radionuclides With Short Half Lives (e.g., 99m Tc @ 6 hrs) No Significant External Radiation Exposure Hazard To Staff or Family Contamination Precautions and Universal Precautions Should Always Be Followed
NRC requires a signed declaration of pregnancy for occupational workers to limit exposures to 500 mrem/9months or 50 mrem in any one month. Pregnancy Declaration
Sources and Doses of Radiation Radiation Dose Received from Various Sources of Natural Background Radiation TypeSource Natural Radiation Source Dose Received (mrem/year) Cosmic: Quasars, Sun, Supernovas Protons; Electrons Neutrons; Muons 26 (at sea level) 50 (Denver, CO) Terrestrial: Oceans, Lakes, Streams, Rocks, Soil Natural Radiation Thorium; Radium; Polonium-210; Lead-210, Potassium-40 16 (Gulf Coast), 30 (Iowa), 63 (Rocky Mtns.) Internal: Food, Milk, Water Potassium-40; Lead-210; Polonium-210 39 Atmospheric:AirPrimarily Radon200 Source of Exposure
Radiation Dose Received From Other Sources of Radiation Type of ExposureRadiation SourceDose Received OccupationalIndustrial, Medical and Academic 0-5000 mrem/year, (Average-500 mrem/year) Cigarettes - 1.5 packs/dayLead-210 and Polonium-210 1300 mrem/year (0.12 mrem/cig) Nuclear Medicine Bone ScanRadioactive Technetium430 mrem Living in a Brick HouseUranium and Thorium75 mrem/year Watching TVLow Energy X-rays30 mrem/year Routine Chest X-rayX-rays10 mrem/film Cooking/Heating with Natural Gas Radon9 mrem/year Airplane Flight - Cross-CountryCosmic Radiation4 mrem/trip Smoke DetectorsAmericium-241<1 mrem/year Nuclear Weapons FalloutCesium-137; Strontium-90<0.3 mrem/year Nuclear Fuel Cycle/Power Plants Nuclear Fuel0.1 mrem/year Source of Exposure
Radiation Exposures from Consumer Products 1 1 Adapted from NCRP 95
Radiation Exposures From ? Smoking a pack and a half of cigarettes a day will add about 1,300 mrem/year to one's effective dose Flying from New York to London results in the absorption of an extra 2-3 mrem of cosmic radiation 6-8 mrem from NY to Japan
For Astronauts ~ 17,000 mrem / yr From Cosmic Radiation
Various degrees of sensitivity to radiation exist due to the type of tissue which receives the exposure RadiosensitiveRadioresistant Breast tissueHeart tissue Bone marrow cellsLarge arteries Mucosa lining of small intestinesLarge veins Sebaceous (fat) glands of skinMature blood cells Immune response cellsNeurons All stem cell populationsMuscle cells Lymphocytes
Biologically Significant Radiation Exposures (Absorbed/Acute Exposure) Risk of contracting cancer increased 0.09%1,000 mrem Temporary blood count change25,000 mrem Permanent sterilization in men100.000 mrem Permanent sterilization in women250.000 mrem Skin Erythema300,000 mrem Cataract formation (20 slices)600,000 mrem
Common Radiation Exposures (Natural Sources and Human Made) One Coast to Coast Flight3 mrem Natural Background Radiation in the U.S. 150 - 300 mrem/year Chest Radiograph, A/P view 15 - 25 mrem/view Chest Radiograph, Lateral view 50 - 65 mrem/view Screening Mammography (film/screen combination) 60 - 135 mrem/view Computerized Tomography of Body (20 slices) 3000 - 6000 mrem
Skin Response (external Radiation) Effect Dose threshold (rad) Approx. Onset Peak Early Transient Erythema 200Hours24 hours Temporary Epilation3003 weeks Main Erythema60010 days2 weeks Permanent Epilation7003 weeks Dry Desquamation1,0004 weeks5 weeks Late Erythema1,5006 – 10 weeks Source: Journal of Vascular and Interventional Radiology, 1994: 5:71-84).
Figure 2(a). Condition of patient's back six to eight weeks following multiple coronary angiography and angioplasty procedures Source: Thomas B. Shope, Ph.D. (HFZ-140) FDA/Center for Devices and Radiological Health
Figure 2(b). Appearance of skin injury approximately 16 to 21 weeks following the procedures with small ulcerated area present. Source: Thomas B. Shope, Ph.D. (HFZ-140) FDA/Center for Devices and Radiological Health
Figure 2(c). Appearance of skin injury approximately 18 to 21 months following procedures, evidencing tissue necrosis. Source: Thomas B. Shope, Ph.D. (HFZ-140) FDA/Center for Devices and Radiological Health
Minimum Latent Periods for Radiation Induced Cancers Leukemia 2 - 3 years Bone Cancers 3 - 4 years Solid Tumors 10 years Medical Management of Radiation Accidents, 1990, p.209, 211 Table 3.
Risks which Increase Chance of Death by 1 in 1 million a a B.L. Cohen and I.S. Lee, ”Catalog of Risks Extended and Updated”, Health Physics, Vol. 61, Sept. 1991.
More Risks which Increase Chance of Death by 1 in 1 million a a B.L. Cohen and I.S. Lee, “Catalog of Risks Extended and Updated”, Health Physics, Vol. 61, Sept. 1991.
Emergency Procedures Follow radiation patient code procedures. If the patient should die or require emergency surgery, contact a member of the Radiation Safety Office immediately at X-2250. Address medical emergency first !! Contact Radiation Safety immediately. Contact Radiation Oncology or Nuclear Medicine immediately as appropriate.