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Radiation Safety: Present and Future Challenges Associated with the Use of Ionizing Radiation. Miroslav Pinak Radiation Safety and Monitoring Section International Atomic Energy Agency. Today’s presentation. from THEORY . to preparing STANDARDS.
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Radiation Safety:Present and Future Challenges Associated with the Use of Ionizing Radiation Miroslav Pinak Radiation Safety and Monitoring Section International Atomic Energy Agency
Today’s presentation from THEORY to preparing STANDARDS to addressing CHALLENGES in APPLICATION
Approach in general What are the developments in the system of radiation protection? Conservative approach in preparing standards Experience and challenges in application Scientific knowledge and assumptions
How to move the best possible way from THEORY to preparing STANDARDS
Current System of Radiological Protection – three categories of exposure The system follows three principles • Justification (all exposure situations) • Optimization of protection with dose constraints (all exposure situations) • Dose limitation (planned exposure situations except for patients)
Current System of Radiological Protection – three categories of exposure The principles are applied in threeexposuresituations Planned Existing Emergency
Current System of Radiological Protection – three categories of exposure and in three categories of exposure Occupational Medical Public
Exposure situations and categories of exposure Types of exposure situations Planned exposure situation Emergency exposure situation Existing exposure situation • = situations involving the planned introduction and operation of sources (including decommissioning, disposal of radioactive waste, rehabilitation) • = unexpected situations such as those that may occur during of a planned situation, or from a malicious act, requiring urgent attention • = situations that already exist when a decision on control has to be taken, such as those by natural background radiation and residues from past practices operated outside the system
STANDARDS in radiation protection and safety preparing STANDARDS
Role of the IAEA in the area of radiation safety As defined in Statute (1989):
Way to establish standards in radiation protection Essentialprinciples (moral obligation) 103 The 2007 Recommendations of the International Commission on Radiological Protection Effects of radiation Recommendations for protection Essentialrequirements (legal obligation)
International Basic Safety Standards (BSS) The International BSS: • is one of the core IAEA standards dealing with radiation safety • is aimed to be the basis for national legislation • establishes criteria for radiation protection of workers, patients, the public and the environment • is based on radiation protection system introduced by ICRP in 2007
Recently released standards A COMPLETE SAFETY GUIDANCE IN RADIATION PROTECTION SSG-46: Radiation Protection and Safety in Medical Uses of Ionizing Radiation GSG-7: Occupational radiation protection GSG-8: Radiation Protection of the Public and the Environment GSG-9: Regulatory Control of Discharges to the Environment GSG-10: Prospective Radiological Environmental Impact Assessment for Facilities and Activities
Few challenges in moving forward to APPLICATION… associated with CHALLENGES from STANDARDS
Few challenges in moving forward • Radiation protection in medicine: • Optimization and justification • Occupational radiation protection: • Increasing number of workers exposed to radiation in the course of their work • Radon: • Awareness and knowledge of the risks • Appropriate regulations and building codes • Exemption and clearance: • Identifying scenarios when regulatory control of the practice or the source produces no net benefit • Food & Drinking Water: • Effort towards harmonized international guidance
Radiation protection in medicine: What is the issue? Statistics • Medical exposure is overwhelmingly the most significant manmade source of exposure to the population from ionizing radiation • Issues around the optimization (e.g. wide variation in doses reported for the same type of CT-scan, order of magnitude) • Issues around the justification (a substantial fraction, ~20-40% of all diagnostic imaging examinations may be inappropriate*) *conclusions of the 2009 IAEA workshop on justification
Radiation protection in medicine: What is the issue? *UNSCEAR Report 2008
Radiation protection in medicine: International guidance • Safety Guide SSG-46 published in October 2018 • Jointly sponsored byIAEA, WHO, PAHO, ILO • Cooperation in development from international/regional professional organizations: • International Organization for Medical Physics (IOMP) • International Society of Radiology (ISR) • International Society of Radiographers and Radiologic Technologists • World Federation of Nuclear Medicine and Biology (WFNMB) • European Society for Therapeutic Radiology and Oncology (ESTRO)
Occupational radiation protection: what is the issue? • The development of the nuclear industry and the more widespread application of radiation and nuclear technologies have led to a steady increase of the number of workers who might be exposed to radiation in the course of their work. • 23 million workers worldwide are exposed occupationally to ionizing radiation, some 75 per cent of them working in the medical field
Occupational radiation protection: International guidance • Implementation of the ORPA Requirements in compliance with International Basic Safety Standards • Jointly developed with ILO • It is applicable to all areas concerning occupational exposure, including medicine, nuclear fuel cycle, industries involving NORM, radiation application industries and scientific as well as educational facilities.
Radon: What is the issue? • Need for awareness, lack of remediation requests and experts • Need for knowledge on potentially problematic workplaces and risk based approach to identification • Regulations, building codes and involvement of interested parties • Efficient verification of compliance mechanisms
Radon: International guidance • Documents under development: • Design and Conduct of Indoor Radon Surveys (in press) • Indoor Radon: Preventative and Corrective Methods (under development) • Regulatory control of building and construction materials (under development) • Protection of Workers against Exposure due to Radon (submitted for approval by RASSC in June 2019)
Exemption and clearance: What is the issue? • Some uses of radiation have such a low level of risk that they can be exempted from regulatory control. • In some cases, regulatory control over certain radiation material or radioactive objects is no longer necessary; this is called clearance.
Exemption and clearance: What is the issue? • The general criteria of exemption and clearance are: • Radiation risks are sufficiently low as to not warrant regulatory control; or • Regulatory control of the practice or the source would produce no net benefit, i.e. no reasonable control measures would achieve a worthwhile return in terms of reduction of individual doses or of health risks • The individual dose is 10 µSvin a year or less • For low probability scenarios, the dose does not exceed 1 mSvin a year.
Exemption and clearance: International guidance • Exemption from Regulatory Control of Goods Containing Small Amounts of Radioactive Material
Food and drinking water: What is the issue? • Not just important after a nuclear or radiological emergency Sources of Radionuclides in the Environment: Natural • Radionuclides of natural origin, particularly radionuclides in the uranium and thorium decay series and 40K, all of which are present throughout the environment. Man-made • Fallout from the testing of nuclear weapons, which occurred primarily in the 1950s and 1960s — the main radionuclides of interest are 90Sr and 137Cs. • Accidental releases of radionuclides e.g. Windscale nuclear reactor fire (1957), Kyshtym accident (1957), Chernobyl NPP (1986), Fukushima Daiichi NPP (2011) Natural and man-made • Authorized discharges from nuclear facilities and other licensed facilities: these are primarily of artificial origin, but may also be of natural origin. • Residual activity from past practices and non-regulated activities.
Food & Drinking Water: International guidance Food and drinking water: What is the issue? BSS Requirement 51: Exposure due to radionuclides in commodities The regulatory body or other relevant authority shall establish specific reference levels for exposure due to radionuclides in commodities such as construction materials, food and feed, and in drinking water, each of which shall typically be expressed as, or be based on, an annual effective dose to the representative person that generally does not exceed a value of about 1 mSv. The regulatory body or other relevant authority shall consider the guideline levels for radionuclides in food traded internationally that could contain radioactive substances as a result of a nuclear or radiological emergency, which have been published by the Joint FAO of the WHO Codex Alimentarius Commission. The regulatory body or other relevant authority shall consider the guideline levels for radionuclides contained in drinking water that have been published by the WHO.
Food & Drinking Water: International guidance Food and drinking water: International guidance IAEA TECDOC 1788: Criteria for Radionuclide Activity Concentrations for Food and Drinking Water Codex Alimentarius Standard 193-1995 (1995) WHO Guidelines for Drinking–water Quality (4th Edition – 2011) International Basic Safety Standards (5th edition – 2014) Different approaches Different timeframes Different purposes
Food & Drinking Water: International guidance Thank you for your kind attention!