2. Radiation Safety and Operations Ibrahim Fibres Ltd.

3. How most of us feel about radiation until we understand the principles of safe use:

4. Radiation Types Non-Ionizing Radiation Ionizing Radiation

5. Radiation from High to Low Frequency

6. Radiation and Radioactive Material are a Natural Part of Our Lives We are constantly exposed to low levels of radiation from outer space, earth, and the healing arts. Low levels of naturally occurring radioactive material are in our environment, the food we eat, and in many consumer products. Some consumer products also contain small amounts of man-made radioactive material. Smoke Detector

7. Unstable Atoms Decay The number of “decays” that occur per unit time in the radioactive material tell us how radioactive it is. – Decays per minute (dpm), and Becquerels (decays per second). When an unstable atom decays, it transforms into another atom and releases it’s excess energy in the form of radiation. Radiation can be – Electromagnetic radiation (like X or gamma rays), and – Particles (like alpha, beta, or neutron radiation) Sometimes the new atom is also unstable, creating a “decay chain”

8. How Unstable Is It? The “Half-Life” describes how quickly Radioactive Material decays away with time. It is the time required for half of the unstable atoms to decay. Some Examples Example: – Some natural isotopes (like uranium and thorium) have half-lives that are billions of years,

9. Some Isotopes & Their Half Lives ISOTOPE ½ Life APPLICATIONS Uraniumbillions of years Natural uranium is comprised of several different isotopes. When enriched in the isotope of U-235, it’s used to power nuclear reactor or nuclear weapons. Carbon-14 5730 y Found in nature from cosmic interactions, used to “carbon date” items and as radiolabel for detection of tumors. Cesium-137 30.2 y Blood irradiators, tumor treatment through external exposure. Also used for industrial radiography. Β- (beta decay): 0.5120 & Γ (gamma-rays): 0.6617 Β- (beta decay)Γ (gamma-rays) Cobalt-60 5.27 y Medical use consists primarily of cancer radiotherapy. Industrial uses include testing welds and castings and a large variety of measurement and test instruments Γ (gamma-rays)Γ (gamma-rays): 1.1732,1.3325 & Β (beta decay): 0.3171.1732,1.3325Β (beta decay) Irridium-19274 dImplants or "seeds" for treatment of cancer. Also used for industrial radiography. Molybdenum-9966 hParent for Tc-99m generator.

10. Alpha particles are the least dangerous in terms of external exposure. Each particle contains a pair of neutrons and a pair of protons. They don't penetrate very deeply into the skin. in fact, clothing can stop alpha particles. Unfortunately, alpha particles can be inhaled or ingested, usually in the form of radon gas. Once ingested, alpha particles can be very dangerous. However, even then they don't typically cause radiation sickness, instead they lead to lung cancer Alpha Particles

11. Beta particles are electrons that move very quickly, that is with a lot of energy. Beta particles travel several feet when emitted from a radioactive source, but they're blocked by most solid objects. A beta particle is about 8,000 times smaller than an alpha particle and that's what makes them more dangerous. Their small size allows them to penetrate clothing and skin. External exposure can cause burns and tissue damage, along with other symptoms of radiation sickness. If radioactive material enters food or water supplies or is dispersed into the air, people can inhale or ingest beta particle emitters unknowingly. Internal exposure to beta particles causes much more severe symptoms than external exposure Beta Particles

12. Gamma rays are the most dangerous form of ionizing radiation. These extremely high energy photons can travel through most forms of matter because they have no mass. It takes several inches of lead or several feet of concrete to effectively block gamma rays. If you're exposed to gamma rays, they pass through your entire body, affecting all of your tissues from your skin to the marrow of your bones. This causes widespread systemic damage. Gamma Rays

13. Four Primary Types of Ionizing Radiation Alpha particles Beta particles Gamma rays (or photons) X-Rays (or photons) Neutrons

14. Shielding for ,  and  BASIC CONCEPT is to: Place materials between the source and person to absorb some or all of the radiation

15. Direct Ionization Protons Alpha Particles Beta Particles Positron Particles Cell damage can be caused by direct or indirect ionization. Direct ionization occurs when charged particles, e.g., electrons, with sufficient kinetic energy interact with cellular atoms or molecules to create free radicals. The process is known as direct because the interaction occurs directly between a particle and a cellular component without an intermediary step. The charged particle can continue to interact with other molecules until all its kinetic energy is lost.

16. Indirect Ionization Neutrons Gamma Rays X-Rays Indirect ionization occurs when non-charged particles, e.g., photons, interact with cellular water. The energy absorbed by an H 2 O molecule results in the formation of ion pairs and reactive oxygen metabolites such as hydroxyl radicals. In turn, these free radicals interact with cellular atoms and molecules damaging cellular proteins and may form additional free radicals. The process is known as indirect because of the intermediate step of H 2 O- based free radical formation.

17. Radiation at the Cellular Level Causes breaks in one or both DNA strands or; Causes Free Radical formation

18. Our Bodies Are Resilient DNA damage is most important and can lead to cell malfunction or death. Our body has ~ 60 trillion cells – Each cell takes “a hit” about every 10 seconds, resulting in tens of millions of DNA breaks per cell each year. – BACKGROUND RADIATION causes only a very small fraction of these breaks (~ 5 DNA breaks per cell each year). Our bodies have a highly efficient DNA repair mechanisms

19. Dividing Cells are the Most Radiosensitive Rapidly dividing cells are more susceptible to radiation damage. Examples of radiosensitive cells are; – Blood forming Cells – The intestinal lining – Hair follicles – A fetus This is why the fetus has a exposure limit (over gestation period) of 500 mrem (or 1/10 th of the annual adult limit)

20. Effects of ACUTE Exposures Dose (Rads*) Effects 25-50 First sign of physical effects (drop in white blood cell count) 100 ~ 1 J/kg Threshold for vomiting (within a few hours of exposure) 320 - 360 ~ 50% die within 60 days (with minimal supportive care) 480 - 540 ~50 % die within 60 days (with supportive medical care) 1,000 ~ 10J/kg ~ 100% die within 30 days

21. Radioactivity Exposure Maximum Dose/year = 5 REM or 50 mSv Maximum Dose/year for Declared Pregnant Woman & Minors= 0.5 REM or 5 mSv

22. Annual Dose Limits External/Internal Exposure Limits for Occupationally Exposed Individuals Adult ( +18 yrs) Minor (< 18 yrs) Whole body*5000 mrem/yr500 mrem/yr Lens of eye15000 mrem/yr1500 mrem/yr Extremities50000 mrem/yr5000 mrem/yr Skin50000 mrem/yr5000 mrem/yr Organ50000 mrem/yr5000 mrem/yr

23. Radiation sickness occurs when high-energy radiation damages or destroys certain cells in your body. Regions of the body most vulnerable to high-energy radiation are cells in the lining of your intestinal tract, including your stomach, and the blood cell-producing cells of bone marrow. Signs and symptoms are also affected by the type of exposure — such as total or partial body. The severity of radiation sickness also depends on how sensitive the affected tissue is. For instance, the gastrointestinal system and bone marrow are highly sensitive to radiation. Causes Radiation is the energy released from atoms as either a wave or a tiny particle of matter. Radiation Sickness

24. The initial signs and symptoms of treatable radiation sickness are usually nausea and vomiting. The amount of time between exposure and when these symptoms develop is a clue to how much radiation a person has absorbed. After the first round of signs and symptoms, a person with radiation sickness may have a brief period with no apparent illness, followed by the onset of new, more-serious symptoms. If you've had a mild exposure, it may take hours to weeks before any signs and symptoms begin. But with severe exposure, signs and symptoms can begin minutes to days after exposure. Possible symptoms include: Nausea and vomiting Diarrhea Headache Fever Dizziness and disorientation Weakness and fatigue Hair loss Bloody vomit and stools from internal bleeding Infections Low blood pressure Initial Signs and Symptoms

25. Incoming Shipments LOOK FOR DAMAGE OR LEAKAGE Use the appropriate survey meter to confirm the TYPE and AMOUNT of detectable radiation is proper Wipe test outer package and run wipes in LSC Check each inner increment of packaging Record the Results on your inventory sheet in the Rad Manual

26. Spill Response On Skin—flush completely On Clothing—remove If Injury—administer first aid Radioactive Gas Release—vacate area, shut off fans, post warning Monitor all persons and define the area of contamination

27. Dose Reduction A.L.A.R.A. As Low As Reasonably Achievable. Limits are the maximums allowable Reduce radiation exposure as much as possible –Improvement/efficiency of procedures and techniques –Better Shielding

28. Radiation Exposure Reduction – Occupational Dose Time – minimize the duration of your exposure Distance – maximize your distance from the source of radiation Shielding – use appropriate shielding