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Basic Radiation Safety Awareness Training Radiation Safety Program 713-500-5840 Environmental Health and Safety.

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1 Basic Radiation Safety Awareness Training Radiation Safety Program 713-500-5840 Environmental Health and Safety

2 Outline History of Radiation History of Radiation Natural & Man-Made Background Sources of Radiation Natural & Man-Made Background Sources of Radiation Fundamentals Fundamentals Exposure Limits & Regulations Exposure Limits & Regulations Detection of Radiation Detection of Radiation Safe Practices with Radiation Safe Practices with Radiation Biological Effects of Radiation Biological Effects of Radiation Where to Find Further Information Where to Find Further Information

3 First Known Human Use of Uranium 79 A D 79 A D Roman artisans produce yellow colored glass in mosaic mural near Naples, Italy Roman artisans produce yellow colored glass in mosaic mural near Naples, Italy

4 Radium Effects Confirmed 1925 1925 Suspicions develop around watch dial painters’ jaw lesions Suspicions develop around watch dial painters’ jaw lesions Dentists diagnose lesions as jaw necrosis due to radium deposits in jaw bone Dentists diagnose lesions as jaw necrosis due to radium deposits in jaw bone Doctor notes bone changes and anemia in dial painters Doctor notes bone changes and anemia in dial painters

5 What is Radiation? What is Radiation? Radiation: energy in motion Radioactivity: spontaneous emission of radiation from the nucleus of an unstable atom Isotope: atoms with the same number of protons, but different number of neutrons Radioisotope: unstable isotope of an element that decays or disintegrates spontaneously, emitting radiation. Approximately 5,000 natural and artificial radioisotopes have been identified

6 Types of Radiation  Non-Ionizing Radiation: Radiation that does not have sufficient energy to dislodge orbital electrons. Examples of non-ionizing radiation: microwaves, ultraviolet light, lasers, radio waves, infrared light, and radar.  Ionizing Radiation: Radiation that has sufficient energy to dislodge orbital electrons. Examples of ionizing radiation: alpha particles, beta particles, neutrons, gamma rays, and x-rays.

7 Radiation Spectrum

8 Radioactive Waste Radon X-Rays Consumer Products Nuclear Power Nuclear Medicine Solar Radiation Cosmic Rays Terrestrial Radiation Food & Drink Each Other     RADIOACTIVE SOURCES

9 Terrestrial Radiation  Common radionuclides created during formation of earth: –Radioactive Potassium (K-40) found in bananas, throughout the human body, in plant fertilizer and anywhere else stable potassium exists. –Radioactive Rubidium (Rb-87) is found in brazil nuts among other things. Terrestrial radiation comes from radioactivity emitting from Primordial radio nuclides - these are radio nuclides left over from when the earth was created.

10 Terrestrial Radiation Greatest contributor is 226 Ra (Radium) with significant levels also from 238 U, 232 Th, and 40 K. Greatest contributor is 226 Ra (Radium) with significant levels also from 238 U, 232 Th, and 40 K. Igneous rock contains the highest concentration followed by sedimentary, sandstone and limestone. Igneous rock contains the highest concentration followed by sedimentary, sandstone and limestone. Fly ash from coal burning plants contains more radiation than that of nuclear or oil-fired plants. Fly ash from coal burning plants contains more radiation than that of nuclear or oil-fired plants.    

11 Let’s Compare Backgrounds Sea level - 30 mrem/year Sea level - 30 mrem/year from cosmic radiation from cosmic radiation 10,000 ft. altitude - 140 mrem/year 10,000 ft. altitude - 140 mrem/year from cosmic radiation from cosmic radiation

12 Consumer Products and Radioactive Material  There are more sources of radiation in the consumer product category than in any other. Television sets - low energy x-rays. Television sets - low energy x-rays. Smoke detectors Smoke detectors Some more products or services: treatment of agricultural products; long lasting light bulbs; building materials; static eliminators in manufacturing; and luminous dials of watches, clocks and compasses Some more products or services: treatment of agricultural products; long lasting light bulbs; building materials; static eliminators in manufacturing; and luminous dials of watches, clocks and compasses

13 Annual Dose to the General Population From Natural and Man-made Sources

14 Annual Dose from Background Radiation Total US average dose equivalent = 360 mrem/year Total exposure Man-made sources Radon Internal 11% Cosmic 8% Terrestrial 6% Man-Made 18% 55.0% Medical X-Rays Nuclear Medicine 4% Consumer Products 3% Other 1% 11%

15 The Anatomy of the Atom

16 Ionization Formation of a charged and reactive atom - - - - The neutral absorber atom acquires a positive charge Beta particle - Colliding coulombic fields Ejected electron

17 Ionizing radiation Occurs from the addition or removal of electrons from neutral atoms Occurs from the addition or removal of electrons from neutral atoms Four main types of ionizing radiation Four main types of ionizing radiation alpha, beta, gamma and neutrons alpha, beta, gamma and neutrons  Alpha  Alpha  Beta  Beta  Gamma (X-ray)  Gamma (X-ray) nNeutron nNeutron

18 Linear Energy Transfer

19 ALARA As Low As Reasonably Achievable As Low As Reasonably Achievable How? How? Time Distance Shielding Why? Why? Minimize Dose

20 Time  Less time = Less radiation exposure  Use RAM only when necessary  Dry runs (without radioactive material)  Identify portions of the experiment that can be altered in order to decrease exposure times  Shorten time when near RAM  Obtaining higher doses in order to get an experiment done quicker is NOT “reasonable”!

21 Distance Effective & Easy Effective & Easy Inverse Square Law Inverse Square Law Doubling distance from source, decreases dose by factor of four Doubling distance from source, decreases dose by factor of four Tripling it decreases dose nine-fold Tripling it decreases dose nine-fold More Distance = Less Radiation Exposure More Distance = Less Radiation Exposure Tongs, Tweezers, Pipettes, Pliers Tongs, Tweezers, Pipettes, Pliers

22 Shielding Materials “absorb” radiation Materials “absorb” radiation Proper shielding = Less Radiation Exposure Proper shielding = Less Radiation Exposure Plexiglass vs. Lead Plexiglass vs. Lead

23 Shielding Examples

24 Shielding used where appropriate Shielding used where appropriate Significantly reduces radiation effects Significantly reduces radiation effects Lead Plexiglas Radiation Shielding

25 labeled Radiation use will be labeled on door, work area & storage area Research laboratories work with very low levels of radioactive materials Safety can check for potential contamination prior to work in a lab that uses radioactive materials wear gloves, safety glasses and wash hands As a precaution: wear gloves, safety glasses and wash hands Radiation Postings

26 Inappropriate Lab Attire

27 Appropriate Lab Attire Lab coat Lab coat Eye protection Eye protection Closed toe shoes Closed toe shoes Personnel monitoring Personnel monitoring Gloves Gloves

28 Route of Entry for Exposure

29 Laboratory Wipe Tests Fill out form RS-8 Fill out form RS-8 Draw map of laboratory Draw map of laboratory Take wipes of surfaces (10 cm 2 ) throughout lab Take wipes of surfaces (10 cm 2 ) throughout lab Run wipes monthly for possible contamination Run wipes monthly for possible contamination Document all information on form and place in Radiation Safety Binder Document all information on form and place in Radiation Safety Binder

30 Common Units Radioactivity Radioactivity Exposure Exposure Absorbed Dose Absorbed Dose Dose Equivalent Dose Equivalent Units are Cool

31 Radioactivity Rate of Decay / Potential to Decay Rate of Decay / Potential to Decay “Strength” “Strength” Curie (Ci) - 1 gram of radium disintegrates Curie (Ci) - 1 gram of radium disintegrates 3.7 X 10 10 disintegration/ second (dps) 3.7 X 10 10 disintegration/ second (dps) Becquerel (Bq) Becquerel (Bq) = 1 disintegration/second (dps) 1 mCi = 37 MBq 1 mCi = 37 MBq

32 Exposure Radioactivity is measured in Roentgens (R) Radioactivity is measured in Roentgens (R) Charge produced in air from ionization by gamma and x-rays Charge produced in air from ionization by gamma and x-rays ONLY for photons in air ONLY for photons in air Rather infrequently used unit Rather infrequently used unit A measure of what is emitted A measure of what is emitted

33 Absorbed Dose Energy deposited by any form of ionizing radiation in a unit mass of material Energy deposited by any form of ionizing radiation in a unit mass of material Roentgen Absorbed Dose (rad) Roentgen Absorbed Dose (rad) Gray (Gy) Gray (Gy) 1 Gy = 100 rad 1 Gy = 100 rad

34 Dose Equivalent Scale for equating relative hazards of various types of ionization in terms of equivalent risk Scale for equating relative hazards of various types of ionization in terms of equivalent risk Damage in tissue measured in rem Damage in tissue measured in rem (Roentgen Equivalent Man) (Roentgen Equivalent Man) Q:risk of biological injury Q:risk of biological injury rem = Q * rad rem = Q * rad Sievert (Sv) Sievert (Sv) 1 Sv = 100 rem 1 Sv = 100 rem

35 What do we really need to know? 1 R  1 rad = 1 rem 1 R  1 rad = 1 rem For gammas & betas* For gammas & betas* 1 rad  1 rem 1 rad  1 rem For alphas, neutrons & protons For alphas, neutrons & protons 1 rem = 1 rad * Q 1 rem = 1 rad * Q

36 And why do we want to know it? Dosage and dosimetry are measured and reported in rems. Dosage and dosimetry are measured and reported in rems. All the Federal and State regulations are written in rems. All the Federal and State regulations are written in rems. The regulators must be placated with reports in rems. The regulators must be placated with reports in rems.

37 Annual Radiation Exposure Limits Occupationally Exposed Worker: remmrem Whole body 55000 Eye1515,000 Shallow5050,000 Minor0.5500 Pregnant Worker 0.5*500* _____________*9 months_ General Public: 100 mrem/year or 2mrem/hour

38 Why Establish Occupational Exposure Limits? We want to eliminate ability of We want to eliminate ability of non-stochastic effects (Acute) to occur Example: Skin Reddening Example: Skin Reddening We want to reduce the probability of the occurrence of We want to reduce the probability of the occurrence of stochastic effects (Chronic) stochastic effects (Chronic) to same level as other occupations Example: Leukemia Example: Leukemia Established from Accident Data Established from Accident Data

39 Whole Body Total Effective Dose Equivalent (TEDE) Total Effective Dose Equivalent (TEDE) TEDE = Internal + External TEDE = Internal + External Assume Internal Contribution Zero Assume Internal Contribution Zero Unless Ingestion, Absorption or Inhalation Suspected Unless Ingestion, Absorption or Inhalation Suspected Limit = 5 rem / yr Limit = 5 rem / yr

40 Ensuring Compliance to Radiation Exposure Limits Use the established activity limit for each isotope Use the established activity limit for each isotope Compare with similar situations Compare with similar situations Estimate with meter Estimate with meter Calculate Calculate Time, Distance, Shielding, Type, Energy, Geometry Time, Distance, Shielding, Type, Energy, Geometry Measure Measure TLD Chip, Luxel TLD Chip, Luxel Bioassay Bioassay

41 Who should wear radiation dosimeters or badges? Those “likely” to exceed 10% of their annual limit are required Those “likely” to exceed 10% of their annual limit are required Those who would like a badge Those who would like a badge Minors & Declared Pregnant Workers* Minors & Declared Pregnant Workers*

42 Types of Badges Available

43 Rules, Rights & Responsibilities as a Radiation Worker Department of State Health Services Department of State Health Services Radiation Control Radiation Control Texas Regulations for Control of Radiation Texas Regulations for Control of Radiation In Accordance with Texas Radiation Control Act, Health & Safety Code, Ch 401 In Accordance with Texas Radiation Control Act, Health & Safety Code, Ch 401 25 TAC (Texas Administrative Code) 289 25 TAC (Texas Administrative Code) 289

44 Detection of Radiation

45 Radiation Detectors General Classes of Detectors General Classes of Detectors Gas-Filled Detectors Gas-Filled Detectors Solid Detectors Solid Detectors Liquid Detectors Liquid Detectors

46 Gas-Filled Detectors Proportional Counter Proportional Counter Ion Chambers Ion Chambers Geiger-Mueller Counters Geiger-Mueller Counters Main Difference - Charge Multiplication Main Difference - Charge Multiplication

47 Liquid Scintillation Counter (LSC) Liquid Scintillation Counter (LSC)

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49 More Radiation Misconceptions Radiation does not give you super human powers Radiation will not make you glow in the dark

50 Summary of Biological Effects of Radiation Radiation may… Radiation may… Deposit Energy in Body Deposit Energy in Body Cause DNA Damage Cause DNA Damage Create Ionizations in Body Create Ionizations in Body Leading to Free Radicals Leading to Free Radicals Which may lead to biological damage Which may lead to biological damage

51 Radiation Effects on Cells Radio sensitivity Theory of Bergonie & Tribondeau. Radio sensitivity Theory of Bergonie & Tribondeau. Cell are radiosensitive if they : Cell are radiosensitive if they : Have a high division rate Have a high division rate Have a long dividing future Have a long dividing future Are of an unspecialized type Are of an unspecialized type These are the underlying premise for ALARA These are the underlying premise for ALARA

52 Response to radiation depends on: Total dose Total dose Dose rate Dose rate Radiation quality Radiation quality Stage of development at the time of exposure Stage of development at the time of exposure

53 Whole Body Effects Acute or Nonstochastic Acute or Nonstochastic Occur when the radiation dose is large enough to cause extensive biological damage to cells so that large numbers of cells die off. Occur when the radiation dose is large enough to cause extensive biological damage to cells so that large numbers of cells die off. Evident hours to a few months after exposure (Early). Evident hours to a few months after exposure (Early). Late or Stochastic (Delayed) Late or Stochastic (Delayed) Exhibit themselves over years after acute exposure. Exhibit themselves over years after acute exposure. Genetic Genetic Somatic Somatic Teratogenic Teratogenic

54 Most and Least Radiosensitive Cells Low Sensitivity Mature red blood cells Muscle cells Ganglion cells Mature connective tissues High Sensitivity Gastric mucosa Mucous membranes Esophageal epithelium Urinary bladder epithelium Very High Sensitivity Primitive blood cells Intestinal epithelium Spermatogonia Ovarian follicular cells Lymphocytes

55 Comparison of Administrative, Regulatory and Biological Effect Doses 100% of People Die, CNS Syndrome Permanent Infertility Whole Body Regulatory Limit (5 rem/yr) Eye Regulatory Limit (15 rem/yr) 50% of People Die (450 – 500 rad) Nausea & Vomiting (10% of People) Whole Body UTHSCH Administrative Limit (0.125 rem/month) Whole Body Exposure Partial Body Exposure Extremities Regulatory Limit (50 rem/yr) Eye UTHSCH Administrative Limit (0.375 rem/month) Rad or Rem Extremities UTHSCH Administrative Limit (1.275 rem/month) General Public Whole Body Regulatory Limit (0.100 rem/yr) No Clinical Symptoms Seen Below 10 rem Cataract Formation Loss of Hair Skin Reddening Decreased White Blood Cell Count Ulcers on the Skin Molecular Death (> 100,000 rad) Gastrointestinal Syndrome

56 Medical Treatment External Decontamination External Decontamination Mild cleaning solution applied to intact skin Mild cleaning solution applied to intact skin Betadine, Soap, Rad-Con for hands Betadine, Soap, Rad-Con for hands Never use harsh abrasive or steel wool Never use harsh abrasive or steel wool Internal Decontamination Internal Decontamination Treatment which enhances excretion of radionuclides Treatment which enhances excretion of radionuclides

57 How Often Does This Happen? Results of reported exposure-related incidents in Texas 1956 – 2000 Source: Emery, et. al. Only 2% at the Level that Clinical Effects From Radiation Can be Seen (n=3,148)

58 Where to Find More Radiation Safety Information…. Basic Radiation Safety Training (6-hr) Required for All Individuals Working with Radiation Basic Radiation Safety Training (6-hr) Required for All Individuals Working with Radiation July 11 & 12 th – 9 a.m. to Noon (both days) July 11 & 12 th – 9 a.m. to Noon (both days) Call at 713-500-5840 Call at 713-500-5840 Website www.uth.tmc.edu/safety Website www.uth.tmc.edu/safetywww.uth.tmc.edu/safety Radiation Safety Manual Radiation Safety Manual Important Safety Information Posted in Every Laboratory (Yellow) Important Safety Information Posted in Every Laboratory (Yellow)

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