radiation protection program in workplace
5 likes1,596 views
This document discusses the principles of radiation protection in the workplace. It begins with an introduction to radiation safety and why it is needed. It then defines key terms like hazard, radiation, and radiological units. The document outlines occupational exposure limits and the requirements of radiation protection programs, including justification, optimization and dose limitation. It discusses methods for protecting against external exposure through time, distance and shielding. Protection against internal exposure and contamination is also covered. The document concludes with an overview of monitoring requirements in radiation protection programs.
radiation protection program in workplace
- 1. R.P.P. in Workplace Rehab O. Abdel Rahman Associate Prof. of Chemical Nuclear Engineering Hot Laboratory & Waste Management Center AEAE alaarehab@yahoo.com
- 2. Atomic Energy Authority of Egypt Content • Introduction • Radiological Units • Occupational exposure limits • RP. Requirements • Protection against external/internal exposure and contamination. • Monitoring in R.P.
- 3. Atomic Energy Authority of Egypt Introduction Why we need RP? Safety : the prevention of accidents through • use of appropriate technologies to identify the hazards of workplace • eliminate them before an accident occurs Hazard: chemical or physical condition has the potential for causing damage to people, property, or the environment
- 4. Atomic Energy Authority of Egypt Chemical Hazard (Safety Precautions) a) Toxicity b) Reactivity c) Ignition d)Corrosion e)Radioactive Cyanide Peroxides Oils, Paints Acids Pesticide Hypochlorite Organic cleaning , Alkaline solvents 4 Introduction
- 5. Atomic Energy Authority of Egypt Hazard (Safety Precautions) • Carcinogenic: Examples include waste benzene. • Teratogenic: Examples include waste containing ethylene thiourea, tetra ethyl lead, lead alkylates. • Mutagenic: Examples include vinyl chlorides, DDT, aldrin and dieldrine Introduction
- 6. Atomic Energy Authority of Egypt Radioactive Materials Radioisotope N.F.C By product
- 7. Atomic Energy Authority of Egypt Radioactive materials • Radiation Safety aims to keep radiation exposures--both internal and external--As Low As Reasonably Achievable (ALARA). Safeguard Safety Security Safeguard Safety Security
- 8. Atomic Energy Authority of Egypt Introduction What is radiation? Types of Radiation Non-Ionizing Radiation: Radiation that does not have sufficient energy to dislodge orbital electrons. , i.e. microwaves, ultraviolet light, lasers, radio waves, …. Ionizing Radiation: Radiation that has sufficient energy to dislodge orbital electrons., alpha particles, beta particles, neutrons, gamma rays, and x-rays.
- 9. Atomic Energy Authority of Egypt Introduction
- 10. Atomic Energy Authority of Egypt Introduction • Natural vs Induced
- 11. Atomic Energy Authority of Egypt Current uses • Electricity generation • Radioisotope tracing • Radiography • Gauging • Smoke detectors • Insect control • Increasing genetic variability • Food preservation • Medicine Industry Agriculture
- 12. Atomic Energy Authority of Egypt Introduction 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%
- 13. Atomic Energy Authority of Egypt Exposure Sources
- 14. Atomic Energy Authority of Egypt Early use
- 15. Atomic Energy Authority of Egypt Modern Discovery • 1789, discovery of uranium oxide • 1841, isolation of pure metallic element. • 1896, discovery of radioactive properties of uranium • 1898, discovered two new radioactive elements, polonium and radium.
- 16. Atomic Energy Authority of Egypt Early uses • U, Th, and/or K-40, were used to produce glazes used for tiles, pottery, and other ceramics. • As recently as the 1930s, Fiestaware used uranium oxides to create the distinctive orange-red color of its dinnerware.
- 17. Atomic Energy Authority of Egypt Early uses The hands and faces of some clocks, watches, and ship and airplane instruments were painted with paints containing radium (α, β, γ) to make them glow in the dark Radium was actually thought to be a health-giving substance and was used in tonics! Curietherapy in France
- 18. Atomic Energy Authority of Egypt Early health effect • Radium Girls • Mine worker • X-ray specialist Stochastic vs. deterministic
- 19. Atomic Energy Authority of Egypt Health effect • 5-50 rem changes in blood chemistry • 50-90 rem nausea, Fatigue, Vomiting, hair loss, Diarrhea (2-3weeks) • 100-400 Hemorrhage, possible death within 2 months • 1,000 Destruction of intestinal lining, internal bleeding and death(1-2 weeks) • 2,000 Damage to central nervous system loss of consciousness; and death minutes hours to days Sv is defined as the dose equivalent arising from an absorbed dose of 1 Gy. 1Sv= 100 rem),
- 20. Atomic Energy Authority of Egypt Radiological Units • Radioactivity • Exposure • Absorbed Dose • Dose Equivalent
- 21. Atomic Energy Authority of Egypt Radiological Units Radioactivity====== Strength • Rate of Decay / Potential to Decay • Becquerel (Bq) = 1 disintegration/second (dps) • Curie (Ci) - 1 gram of radium disintegrates 3.7 X 1010 disintegration/second (dps) • 1 mCi = 37 MBq
- 22. Atomic Energy Authority of Egypt Radiological Units • Exposure: Charge produced in air from ionization by gamma and x-rays (up to 3MeV) – ONLY for photons in air – Measured in Roentgens (R) – Exposure rater R/s or mR/h Emission of 1 esu (3.336 l0–10 C) of charge of either sign produces in 1 cm3 of air at atm. pressure and 0 C
- 23. Atomic Energy Authority of Egypt Radiological Units Absorbed dose: amount of energy deposited per unit mass • 1 rad = 100 erg/g of medium • Gray (Gy)===SI unit • 1 Gy =1 J/kg= 100 rad
- 24. Atomic Energy Authority of Egypt Radiological Units • Dose equivalent: different radiations produce • different amounts of biological damage even though the deposited energy may be the same • Rem=Q * rad – (Roentgen Equivalent Man) • Q=quality factor risk • 1 Sv = 100 rem (SI unit) • Normally 1-3 mSv/year • In areas of high background, 3-13 mSv/year
- 25. Atomic Energy Authority of Egypt Radiological Units
- 26. Atomic Energy Authority of Egypt Occupational exposure limits NRC exposure limits 10CRF PART 20: • No worker at a nuclear facility will receive an acute whole body radiation exposure sufficient to trigger the radiation syndrome • Risk of cancer (although not zero) will not be higher than the risk of cancer from other • occupations
- 27. Atomic Energy Authority of Egypt Radiation protection requirements • Justification of practice • Optimization of protection • Individual dose limits
- 28. Atomic Energy Authority of Egypt Radiation protection requirements Justification • Decisions on justification are largely influenced by broader political, economic and social concerns • Medical exposures is justified by weighing the diagnostic/ therapeutic benefits against radiation detriment • Disposal of radioactive wastes: consequences or parts of practices need to be justified
- 29. Atomic Energy Authority of Egypt Radiation protection requirements Dose limitation • Restrictions are required on the dose that might be incur or their likelihood of exposure (potential exposure) • It is supplemented by risk limits (probability & consequences).
- 30. Atomic Energy Authority of Egypt Radiation protection requirements Optimization: Protection and safety shall be optimized in order that the magnitude of • individual doses, • number of people exposed and • likelihood of incurring exposures Kept as ALARA, economic and social factors are considered,
- 31. Atomic Energy Authority of Egypt
- 32. Atomic Energy Authority of Egypt
- 33. Atomic Energy Authority of Egypt • time • distance • shielding Protection against external exposure
- 34. Atomic Energy Authority of Egypt Protection against external exposure Methods to minimize the time minimize the time spent in a radiation field • Plan and review the job under realistic conditions • Know the exact location of work prior to entering the radiation area • Ensure all necessary tools are available at the job location • Establish good communications
- 35. Atomic Energy Authority of Egypt Protection against external exposure Some ways to increase the distance on a job are: • Using extension tools, • Utilizing remote operating stations, and • Staying away from hot spots.
- 36. Atomic Energy Authority of Egypt Protection against external exposure Shielding types • Installed: permanent to reduce the radiation levels in some areas. (i.e. concrete shield walls located in the containment). • Temporary: to reduce radiation levels in large areas or shaped to provide the maximum shielding effectiveness (i.e lead sheets, bricks, or bags filled with lead shot.
- 37. Atomic Energy Authority of Egypt Protection against external exposure
- 38. Atomic Energy Authority of Egypt Protection against external exposure • Posting label and precautions
- 39. Atomic Energy Authority of Egypt Protection against internal exposure • Intakes of radioactive material are controlled by the Annual Limit on Intake (ALI) • One ALI equals 5 rems internal dose
- 40. Atomic Energy Authority of Egypt Protection against contamination • Utilize containments • Maintain access control • Conduct frequent surveys • Utilize protective clothing • Wear respiratory protection • Practice good housekeeping • Conduct follow up bioassays • Minimize radioactive leakage • Lab coat • Eye protection • Closed toe shoes • Personnel monitoring • Gloves
- 41. Atomic Energy Authority of Egypt Monitoring Requirements for monitoring equipment selection should be based on – Sensitivity: equipment should have sufficient sensitivity to assess dose below limit, i.e. NORM <1mSv /y – Accuracy: (avoid bias, minimize uncertainties) – Equipment suitability
- 42. Atomic Energy Authority of Egypt Monitoring • Graded approach for establishing a monitoring program Two kinds of monitoring are used • Survey (used to determine the extent of possible contaminations, exposure rate i.e. gm) • Personal (Radiation film badges , pocket dosimeter )
- 43. Atomic Energy Authority of Egypt Radiation safety in workplace
- 44. Atomic Energy Authority of Egypt • Thanks
- 45. Atomic Energy Authority of Egypt Thermoluminescent dosemeters (TLD) • Measurement range 0. 1 mSv to 5 Sv • Only issued if risk assessment concludes they are required
- 46. Atomic Energy Authority of Egypt Electronic Dosimeters • Give an instant reading of dose. • Measurement range 0.001 mSv to 1 Sv
- 47. Atomic Energy Authority of Egypt Other Monitoring • Extremity – rings - tlds or electronic • Eye - tlds • Internal – e.g Iodine uptake – doserate measurements – swabs – samples
- 48. Atomic Energy Authority of Egypt Other Monitoring • Extremity – rings - tlds or electronic • Eye - tlds • Internal – e.g Iodine uptake – doserate measurements – swabs – samples
- 49. Atomic Energy Authority of Egypt Part 4, lecture 1: General principles 52
Editor's Notes
- #5: Toxic wastes are harmful when ingested, inhaled or absorbed through the skin. Reactive wastes are unstable material under normal condition and can cause explosion, Toxic fumes, and gases or vapour. Ignitable wastes are those which readily catch fire and sustain combustion Corrosive wastes are acid or alkaline and can readily corrode or dissolve flesh, metal or other materials acids from metals cleaning processes eg ferric chloride from printed circuit board manufacture liquor from steel manufacture
- #6: Ecotoxic: waste which may have toxic effects on biotic systems and which if released may present immediate or delayed environmental adverse impacts by means of bioaccumulation and/or toxic effects on one or more sectors of the environment. Carcinogenic waste which, if inhaled or ingested or penetrates the skin, may induce cancer in man or increase its incidence Teratogenic: waste containing substances and preparations which if inhaled or taken internally or penetrates the skin may induce non-hereditary genetic deformations, or increase their incidence. Mutagenic: waste containing substances and preparations, which if inhaled or taken internally or penetrates the skin may induce hereditary inherent deformations, or increase their incidence.
- #8: What are the sources in each area?? depleted uranium sheild of some sources, and Pu sources
- #9: The cautious assumption that a proportional relationship exist between dose and effect for all doses
- #12: Radioactive Potassium (K-40) found in bananas, throughout the human body, in plant fertilizer and anywhere else stable potassium exists. For example, the radiation exposure from consuming a banana is approximately 1% of the average daily exposure to radiation, which is 100 banana equivalent doses (BED). The maximum permitted radiation leakage for a nuclear power plant is equivalent to 2,500 BED (250 μSv), while a chest CT scan delivers 70,000 BED (7 mSv). A lethal dose of radiation treatment is approximately 80,000,000 BED (8 Sv). A person living 10 miles from the Three Mile Island nuclear reactor received 700 BED of exposure to radiation It makes up 0.012% (120 ppm) of the total amount of potassium found in nature. Radioactive Rubidium (Rb-87) is found in brazil nuts among other things Greatest contributor is 226Ra (Radium) with significant levels also from 238U, 232Th, and 40K. 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 40K constitutes 120 parts per million of stable potassium which is an essential trace element in every human body 40K has a half-life of 1.28 x 109 years, decaying by beta emission (Emax 1.3 MeV) An 80 kg adult male contains about 180 g of potassium -&gt; 18 mg of 40K This gives an annual internal effective dose of 170 µSv
- #14: Annual Dose from Background Radiation
- #15: EPA
- #16: 79 A D Roman villa on Cape Posillipo in the Bay of Naples, Italy Roman artisans produce yellow colored glass in mosaic mural near Naples, Italy (1%UO2) ,
- #17: German chemist, Martin Heinrich Klaproth, announced the discovery of a new element in 1789. He had been analysing a mineral called pitchblende and discovered in it a black powder. This powder was incorrectly called uranium, but was actually one of its oxides. It was not until 1841 that French scientist, Eugene Péligot isolated the pure metallic element. In 1896, the French physicist Antoine Becquerel discovered the radioactive properties of uranium. Marie and Pierre Curie, the French/Polish scientists, continued to explore radioactivity, and in 1898 found that it was associated with atoms. They also discovered two new radioactive elements, polonium and radium, from pitchblende
- #18: 1960 (, , ) Starting around 1970, the intentional use of radioactive coloring agents in commercial glazes and glasses dramatically decreased. However their use continues in other countries
- #19: 1970 http://www.epa.gov/radtown/antiques.html http://www.epa.gov/radiation/radionuclides/radium.html http://www.uraniumsa.org/uses/early_uses.htm http://itotd.com/articles/654/the-discovery-of-radium/ Radium was actually thought to be a health-giving substance and was used in tonics! Radium was used as additive in products such as toothpaste, hair creams, and even food items due to its supposed curative powers. One of the first uses of radium was as an anti-cancer treatment, owing to its observed ability to damage tissue. The resulting treatment, known as Curietherapy in France, and radiumtherapy elsewhere
- #21: This slide and the following are from part 3 of the course and hidden at present - the lecturer can include them in the presentation if it appears that deterministic and stochastic effects should be reviewed. Deterministic effects are for example: skin reddening (erythema) skin breakdown (desquamation) cataracts in the lens of the eye tumor cell kill death
- #22: The major stochastic effect is cancer induction - however, also many hereditary effects are stochastic. The risk of having a malformation in a baby increases with dose- the severity of the event though is independent of it.
- #23: IAEA
- #26: Physics for rp, 3rd ed 2013 The roentgen was originally defined as that amount of x-radiation or gamma radiation such that the associated corpuscular emission produces in 0.001293 g of air (1 cm3 of air at atmosphere pressure and 0 C) 1 electrostatic unit (1 esu = 3.336 l0–10 C) of charge of either sign. The ionization produced by the associated corpuscular emissions is due to photoelectric, Compton, and, if applicable, pair production interactions.
- #27: Rad is radiation absorbed dose
- #28: 1 R 1 rad = 1 rem For gammas & betas* 1 rad 1 rem For alphas, neutrons & protons 1 rem = 1 rad * Q
- #31: The primary aim of radiological protection is to provide appropriate standards of protection for humans from practices involving radiation exposure, without unduly limiting the benefits of these practices. The system of radiological protection for proposed and continuing practices is based on the following general principles: The justification of a practice. No practice involving exposure to radiation should be adopted unless it produces sufficient benefit to the exposed individual or to society to offset the radiation detriment it causes. The optimization of protection. All exposures shall be kept as low as reasonably achievable, economic and social factors being taken into account Individual dose limits. The dose equivalent to individuals shall not exceed the recommended dose limits.
- #32: Some practices are not justified in terms of radiation protection because they result in frivolous exposure. Examples of such practices are the incorporation of radioactive substances into foods, cosmetics and toys
- #33: For justified practices, other than those involving medical exposures, restrictions on dose that an individual may incur (dose limits) shall be imposed to ensure that no person be subject to an unacceptable risk attributable to radiation exposure
- #34: Radiaiton sources 1000 dose constraint is the value of an individual dose not to be exceeded in the individual dose distribution considered in the optimization process. It is a source related quantity, i.e. it refers to the source, practice or task to which the optimization process is applied. As a ceiling on the individual dose, the constraint is used to restrict the inequity of the distribution of benefits and detriments amongst the population that could result from economic and social judgements. The value of the dose constraint shall not exceed an appropriate fraction of the relevant dose limit, to take account of the fact that individuals may also accumulate doses from other sources.Dose constraints are not limits. They are used Since radiodiagnosis and radiotherapy necessitate medical exposure of patients, optimization objectives shall be adapted for the protection of patients. Doses shall be optimized consistent with obtaining the desired result from the examination or treatment, and the risk of errors in the delivery of such doses shall be maintained ALARA
- #35: Occupiton al radioation proteciton
- #37: External Exposure External exposure precautions may be necessary when working with photon emitters or high energy beta emitters such as P-32. Exposure is controlled by three basic factors: time, distance and shielding.
- #46: GM-counters are sensitive for low levels of radiation GM counters are sensitive for -, -, and -radiation provided the particle energy is sufficient for penetrating the detector entrancewindow. Warning the mR/hr reading of the GM-counter will be usually lower than the real exposure rate due to the low energy absorption in the monitor window GM counters are best used for radiation detection not for measurement of dose GM counters can be calibrated for absorbed dose reading by usingcalibrated -sources
- #53: The lecturer can point out that a) all are above 2mSv/year b) all are below 10mSv/year c) there is a wide variability