NRRC-R-01 Radiation Safety V2 PDF

2022 Regulation Radiation Safety NRRC-R-01 Preamble In accordance with the provisions of the Law of Nuclear and Radiological Control issued by Royal Decree No. (M/82) dated 25/7/1439 AH, and the mandate of Nuclear and Radiological Regulatory Commission (NRRC) stated in its Statute is...

2022 Regulation Radiation Safety NRRC-R-01 Preamble In accordance with the provisions of the Law of Nuclear and Radiological Control issued by Royal Decree No. (M/82) dated 25/7/1439 AH, and the mandate of Nuclear and Radiological Regulatory Commission (NRRC) stated in its Statute issued by Cabinet Resolution No. (334) dated 25 /6/1439 AH, the NRRC prepared regulations that ensure control over radiological activities and practices as well as nuclear and radiological facilities. This regulation has been prepared on the basis of International Atomic Energy Agency (IAEA) standards, international best practices and the experiences of similar international regulatory bodies, and in accordance with the Kingdom's international commitments. This regulation has been approved by the NRRC’s Board of Directors in resolution No. (Q/1/1/2022), dated 9/19/1443 AH. Radiation Safety – NRRC-R-01 Table of Contents Chapter 1: Objective, Scope, Exclusions and Definitions.............................................................. 6 Objective................................................................................................................................................... 6 Scope........................................................................................................................................................ 6 Exclusions................................................................................................................................................. 6 Definitions................................................................................................................................................ 7 Chapter 2: General Requirement on the Application of System of Protection............................ 25 Justification............................................................................................................................................. 25 Demonstration of the justification of practices...................................................................................... 25 Optimization of Protection and Safety................................................................................................... 26 Dose Constraints..................................................................................................................................... 26 Reference Levels..................................................................................................................................... 27 Dose Limits......................................................................................................................................... 27 Chapter 3: Responsibilities for Protection and Safety................................................................ 28 General Responsibilities..................................................................................................................... 28 Management System......................................................................................................................... 29 Safety Culture..................................................................................................................................... 29 Human Factors................................................................................................................................... 30 Chapter 4: Bases of Protection in Planned Exposure Situations................................................. 31 General Requirement......................................................................................................................... 31 Categorization of Sealed Sources....................................................................................................... 31 Prohibition of Practices...................................................................................................................... 31 Requirements for Notification........................................................................................................... 31 Exemption of Practices and Sources.................................................................................................. 32 Exemption Under a Decision by the NRRC......................................................................................... 33 Requirements for Authorization........................................................................................................ 33 Authorization Process........................................................................................................................ 34 Release From Regulatory Control...................................................................................................... 34 Chapter 5: Requirements for the Management of Protection and Safety................................... 34 Prime Responsibility for Protection and Safety................................................................................. 34 Radiation Protection Program............................................................................................................ 35 Radiation Safety Officer..................................................................................................................... 35 Qualified Expert................................................................................................................................. 36 Technical Service Organization.......................................................................................................... 36 Investigations and feedback of information on operating experience.............................................. 36 Regulatory Inspection of Facility........................................................................................................ 37 Information Requested by the NRRC................................................................................................. 37 2 Radiation Safety – NRRC-R-01 Chapter 6: Prevention and Mitigation of Accidents................................................................... 37 Good Engineering Practice................................................................................................................. 37 Defence in Depth............................................................................................................................... 37 Prevention of Radiation Safety Deviations......................................................................................... 38 Chapter 7: Verification of Safety............................................................................................... 38 Safety Assessment.............................................................................................................................. 38 Monitoring, Testing and Verification of Compliance......................................................................... 39 Chapter 8: Emergency Preparedness and Response.................................................................. 39 Emergency Planning........................................................................................................................... 39 Implementation of the Emergency Plan............................................................................................ 40 Action in an Emergency Situation...................................................................................................... 40 Chapter 9: Human Imaging for Purposes other than Medical Diagnosis, Medical Treatment or Biomedical Research................................................................................................................ 40 Justification of Practices Involving the Deliberate Exposure of Humans for Non-Medical Imaging Purposes........................................................................................................................................................... 40 Optimization of Protection and Safety............................................................................................... 41 Chapter 10: Occupational Exposure.......................................................................................... 41 Principal Responsibilities.................................................................................................................... 41 Management Requirements for the Protection of Workers, Apprentices, and Students................. 42 Controlling occupational exposure for outside workers.................................................................... 43 Responsibilities of Workers................................................................................................................ 43 Classification of Areas........................................................................................................................ 44 Requirements for Controlled Areas................................................................................................... 44 Requirements for Supervised Areas................................................................................................... 45 Local Rules and Procedures................................................................................................................ 45 Personal Protective Equipment.......................................................................................................... 46 Workplace Monitoring....................................................................................................................... 46 Individual Monitoring and Assessment of Occupational Exposure.................................................... 46 Records of Occupational Exposure.................................................................................................... 47 Access to Records of Occupational Exposure and Reporting of Dosimetry Results........................... 48 Workers’ Health Surveillance for Radiation Exposure....................................................................... 48 Special Health Surveillance................................................................................................................ 49 Information, Instruction, and Training............................................................................................... 49 Conditions of Service.......................................................................................................................... 50 Age Limits for Occupational Exposure and Special Arrangements for Persons Under 18 Years of Age........................................................................................................................................................... 50 Protection of Pregnant and Breastfeeding Workers.......................................................................... 50 Chapter 11: Public Exposure..................................................................................................... 51 Responsibilities for the Protection of the Members of the Public..................................................... 51 Control of Visitors.............................................................................................................................. 52 External Exposure and Contamination in Areas Accessible to Members of the Public..................... 52 3 Radiation Safety – NRRC-R-01 Assessment of Doses to a Member of the Public............................................................................... 53 Monitoring Programs......................................................................................................................... 53 Reporting and Publishing of Monitoring Results............................................................................... 53 Chapter 12: Medical Exposure.................................................................................................. 54 Regulatory Control for Medical Exposure.......................................................................................... 54 Justification of medical exposures..................................................................................................... 54 General Requirements for the Personnel with Responsibilities for Medical Radiological Exposures 55 Primary Requirements for the Control of the Medical Radiological Exposures of a Patient............. 55 Involvement of Medical Personnel in Medical Exposures................................................................. 56 Optimization of Protection and Safety............................................................................................... 56 Procedures......................................................................................................................................... 57 Calibration.......................................................................................................................................... 57 Patients Dosimetry............................................................................................................................. 58 Use of Diagnostic Reference Levels................................................................................................... 58 General Requirements for the Control of the Medical Radiological Equipment............................... 58 Quality Assurance for Medical Exposure........................................................................................... 58 Special Protection of Pregnant or Breast-feeding Female Patients................................................... 59 Release of Patients After Radionuclide Therapy................................................................................ 60 Medical Exposures as Part of a Research Program............................................................................ 60 Protection of Carers and Comforters................................................................................................. 60 Prevention of Unintended and Accidental Medical Radiological Exposure....................................... 61 Investigation of Unintended and Accidental Medical Radiological Exposures.................................. 61 Radiological Reviews.......................................................................................................................... 62 Records............................................................................................................................................... 62 Chapter 13: Safety of Radiation Generators and Radioactive Sources........................................ 63 General Design Requirements........................................................................................................... 63 The commitment of a Supplier for Accepting the Return of a Disused Sealed Source...................... 64 Requirements for the Management of Radiation Generators and Radioactive Sources................... 64 Locations to Use or Storage of Radiation Sources............................................................................. 65 Record-keeping.................................................................................................................................. 65 Reporting to the NRRC....................................................................................................................... 65 Chapter 14: Consumer Products............................................................................................... 66 Authorization of Consumer Products................................................................................................. 66 Responsibilities of Providers of Consumer Products......................................................................... 66 Labeling of Consumer Products......................................................................................................... 66 Information and Instructions to Users of Consumer Products.......................................................... 66 Information and Instructions to Consumer Product Retailers........................................................... 67 Chapter 15: Radioactive Waste Management........................................................................... 67 General Responsibilities for the Management of Radioactive Wastes.............................................. 67 Control of Radioactive Waste Generation......................................................................................... 67 4 Radiation Safety – NRRC-R-01 Characterization, Classification, and Collection of Radioactive Waste.............................................. 67 Acceptance Criteria for Radioactive Waste........................................................................................ 68 Discharge of Radioactive Materials to the Environment................................................................... 68 Clearance and its Control................................................................................................................... 68 Radioactive Waste records and Report.............................................................................................. 69 Chapter 16: Existing Exposure Situations.................................................................................. 69 Regulatory Requirement for Existing Exposure Situation.................................................................. 69 General Responsibilities for the Management of Existing Situations................................................ 70 Specific Requirements for the Remediation of Areas with Residual Radioactive Material............... 70 Occupational Exposure...................................................................................................................... 72 Control of the Aircrew Exposure Due to Cosmic Radiation............................................................... 72 Chapter 17: Emergency Exposure Situations............................................................................. 72 General Responsibilities for the Emergency Response...................................................................... 72 Protection of Workers in Emergency Exposure Situations................................................................ 72 Protection of Workers Involved in the Transition from an Emergency Exposure Situation to an Existing Exposure Situation....................................................................................................................................................... 73 Appendix 1 Categorization of Radioactive Sources.............................................................. 74 Table of References 5 Radiation Safety – NRRC-R-01 Chapter 1: Objective, Scope, Exclusions and Definitions Objective 1. This regulation shall set out the general safety requirements in ensuring protection of people and the environment against the harmful effects of ionizing radiation and for the safety of radiation sources. 2. This regulation shall harmonize the requirements applicable in the Kingdom with the international best practices in order to achieve the highest standards of safety in activities and facilities that give rise to radiation risks. Scope 3. This regulation applies to all activities and facilities including practices, that are carried out in the Kingdom which involve, or could involve, risk from exposure to ionizing radiation in planned, emer- gency and existing situations. 4. This regulation shall be applicable to occupational, public and medical exposure in the Kingdom. 5. The safety requirements set forth in this regulation shall apply to any person involved in activities and facilities including practices defined under the Law as specified in this regulation. 6. Other safety requirements, complementary to this regulation shall apply for certain activities and facilities, such as for nuclear installations. 7. This regulation is complemented by specific requierment for radiation protection and safety as spec- ified by NRRC. Exclusions 8. The following exposures are excluded from the scope of this regulation: (a) Exposures from natural radioactivity in the body; (b) Cosmic radiation at the surface of the earth; (c) Any other radiation sources that are essentially unamenable to control as may be deter- mined by the NRRC. 6 Radiation Safety – NRRC-R-01 Definitions Absorbed dose, D The fundamental dosimetric quantity D, defined as: d𝜀𝜀̅ 𝐷𝐷 = d𝑚𝑚 where d𝜀𝜀̅ is the mean energy imparted by ionizing radiation to matter in a volume element and dm is the mass of matter in the volume element. Accident Any unintended event, including operating errors, equipment failures and other mishaps, the consequences or potential consequences of which are not negligible from the point of view of protection and safety. Activation The process of inducing radioactivity in the matter by irradiation of that matter. Activity The production, use, possession, storage, transport, import, or export of radioactive, nuclear or nuclear-related items; the siting, construction, commissioning, operation or decommission- ing of facilities; radioactive waste management and site rehabilitation; or any other act speci- fied by the Commission in accordance with its laws. Activity (A) The quantity A, for an amount of radionuclide in a given energy state at a given time, defined as: d𝑁𝑁 𝐴𝐴(𝑡𝑡) = d𝑡𝑡 where d𝑁𝑁 is the expectation value of the number of spontaneous nuclear transformations from the given energy state in the time interval d𝑡𝑡. Ambient dose equivalent, H*(d) The dose equivalent that would be produced by the corresponding aligned and expanded field in the International Commission on Radiation Units and Measurements (ICRU) sphere at a depth 𝑑𝑑 on the radius vector opposing the direction of the aligned field. Annual dose The dose from external exposure in a year plus the committed dose from intakes of radionu- clides in that year. 7 Radiation Safety – NRRC-R-01 Applicant Any person applying to the NRRC for authorization to undertake specified activities and facili- ties including practices. Strictly, an applicant would be such from the time at which an appli- cation is submitted until the requested authorization is either granted or refused. Area monitoring A form of workplace monitoring in which an area is monitored by taking measurements at different points in that area. Assessment The process, and the result, of analyzing systematically and evaluating the hazards associated with sources and practices, and associated protection and safety measures. Authorization The granting by the NRRC of written permission for a person to conduct specified activities. Authorized limit A limit on a measurable quantity, established or formally accepted by the NRRC. Authorized person Person granted authorization under this regulation and/or the relevant Commission Laws. Carers and comforters Persons who willingly and voluntarily help (other than in their occupation) in the care, support and comfort of patients undergoing radiological procedures for medical diagnosis or medical treatment. Clearance The removal of radioactive material or radiation source subject to the Law from the control imposed thereon by the NRRC because the radiation exposure resulting therefrom is too small to warrant the application of such control. Clearance level A value, established by the NRRC and expressed in terms of activity (A) concentration, at or below which regulatory control may be removed from a source of radiation within a notified or authorized practice. Committed dose The lifetime dose expected to result from an intake. 8 Radiation Safety – NRRC-R-01 Committed effective dose, E(τ) The quantity 𝐸𝐸(𝜏𝜏), defined as: 𝐸𝐸(𝜏𝜏) = 𝑤𝑤T ∙ 𝐻𝐻T (𝜏𝜏) T where 𝐻𝐻T (𝜏𝜏) is the committed equivalent dose to tissue or organ T over the integration time 𝜏𝜏 elapsed after an intake of radioactive substances and 𝑤𝑤T is the tissue weighting factor for tissue or organ T. When 𝜏𝜏 is not specified, it will be taken to be 50 years for adults and the time to age 70 years for intakes by children or as specified by the NRRC. Confinement Prevention or control of releases of radioactive material to the environment in operation or in accidents. Constraint A prospective and source related value of individual dose (dose constraint) or of individual risk (risk constraint) that is used in planned exposure situations as a parameter for the optimiza- tion of protection and safety for the source, and that serves as a boundary in defining the range of options in optimization. Consumer product A device or manufactured item into which radionuclides have deliberately been incorporated or produced by activation, or which generates ionizing radiation, and which can be sold or made available to members of the public without special surveillance or regulatory control after sale or any product as determined by NRRC. Containment Methods or physical structures designed to prevent or control the release and the dispersion of radioactive substances. Contamination Radioactive substances on surfaces, or within solids, liquids or gases (including the human body), where their presence is unintended or undesirable, or the process giving rise to their presence in such places. Control The function or power or (usually as controls) means of directing, regulating or restraining. 9 Radiation Safety – NRRC-R-01 Controlled area A defined area in which specific protection measures and safety provisions are or could be required for controlling exposures or preventing the spread of contamination in normal work- ing conditions, and preventing or limiting the extent of potential exposures. Decontamination The complete or partial removal of contamination by a deliberate physical, chemical or bio- logical process. Deterministic effect A radiation induced health effect for which generally a threshold level of dose exists above which the severity of the effect is more significant for a higher dose. Diagnostic reference level A level used in medical imaging to indicate whether in routine conditions, the dose to the patient or the amount of radiopharmaceuticals administered in a specified radiological proce- dure for medical imaging is unusually high or unusually low for that procedure. Directional dose equivalent, 𝑯𝑯′(𝒅𝒅, Ω) The dose equivalent that would be produced by the corresponding expanded field in the In- ternational Commission on Radiation Units and Measurements ICRU sphere at a depth 𝑑𝑑 on a radius in a specified direction Ω. Dose 1. A measure of the energy deposited by radiation in a target. 2. Absorbed dose, committed equivalent dose, committed effective dose, effective dose, equivalent dose or organ dose, as indicated by the context. Dose assessment Assessment of the dose(s) to an individual or group of people. Dose constraint A prospective and radiation source related value of individual dose that is used in planned exposure situations as a parameter for the optimization of protection and safety for the source, and that serves as a boundary in defining the range of options in optimization. Dose limit The value of a quantity used in certain specified activities or circumstances that must not be exceeded. 10 Radiation Safety – NRRC-R-01 Effective dose, 𝑬𝑬 The quantity 𝐸𝐸, defined as a summation of the tissue or organ equivalent doses, each multi- plied by the appropriate tissue weighting factor: 𝐸𝐸 = 𝑤𝑤T ∙ 𝐻𝐻T T where 𝐻𝐻T is the equivalent dose in tissue or organ T and 𝑤𝑤T is the tissue weighting factor or tissue or organ T. From the definition of equivalent dose, it follows that: 𝐸𝐸 = 𝑤𝑤T ∙ 𝑤𝑤R ∙ 𝐷𝐷T,R T R where 𝑤𝑤R is the radiation weighting factor for radiation type R and 𝐷𝐷T,R is the average ab- sorbed dose in the tissue or organ T delivered by radiation type R. The SI unit for effective dose is joule per kilogram (J/kg), termed the sievert (Sv). Emergency A non-routine situation that necessitates prompt action, primarily to mitigate a hazard or ad- verse consequences for human health and safety, quality of life, property or the environment. This includes nuclear or radiological emergencies and conventional emergencies such as fires, release of hazardous chemicals, storms or earthquakes. It includes situations for which prompt action is warranted to mitigate the effects of a perceived hazard. Emergency exposure situation A situation of exposure that arises as a result of an accident, a malicious act or other unex- pected events, and requires prompt action in order to avoid or reduce adverse consequences. Emergency plan A description of the objectives, policy and concept of operations for the response to an emer- gency and of the structure, authorities and responsibilities for a systematic, coordinated and effective response. The emergency plan serves as the basis for the development of other plans, procedures and checklists. Emergency preparedness The capability to take actions that will effectively mitigate the consequences of an emergency for human health and safety, quality of life, property and the environment. Emergency procedures A set of instructions describing in detail the actions to be taken by the response personnel in an emergency. 11 Radiation Safety – NRRC-R-01 Emergency response The performance of actions to mitigate the consequences of an emergency for human health and safety, quality of life, property and the environment. It may also provide a basis for the resumption of normal social and economic activity. Emergency worker A person having specified duties as a worker in response to an emergency. Employer A person with recognized responsibilities, commitments and duties towards a worker in the employment of the person by virtue of a mutually agreed relationship. Environment The conditions under which people, animals and plants live or develop and which sustain all life and development; especially such conditions as affected by human activities. Environmental monitoring The measurement of external dose rates due to sources in the environment or of radionuclide concentrations in environmental media. Equivalent dose, 𝑯𝑯𝑻𝑻 The quantity 𝐻𝐻T R , defined as: 𝐻𝐻T R = 𝑤𝑤R ∙ 𝐷𝐷T R where 𝐷𝐷T R is the absorbed dose delivered by radiation type R averaged over a tissue or organ T and 𝑤𝑤R is the radiation weighting factor for radiation type R. When the radiation field is composed of different radiation types with different values of 𝑤𝑤R , the equivalent dose is: 𝐻𝐻T = 𝑤𝑤R ∙ 𝐷𝐷T R R The SI unit for equivalent dose is joule per kilogram (J/kg), termed the sievert (Sv). Exemption The NRRC’s decision that a radiation source or certain radiation practice need not be subject to its partial or full control on the basis that the exposure to radiation resulting from such source or practice is too low to warrant application of such control, or that this is the optimum option available after taking necessary preventive measures for minimizing the risks of expo- sure to ionizing radiation. Event In the context of the reporting and analysis of events, an event is any occurrence unintended by the worker, including operating error, equipment failure or another mishap, and deliberate 12 Radiation Safety – NRRC-R-01 action on the part of others, the consequences or potential consequences of which are not negligible from the point of view of protection and safety. Exemption level A value, established by the NRRC and expressed in terms of activity (A) concentration, total activity (A), dose rate or radiation energy, at or below which a source of radiation need not be subject to some or all aspects of regulatory control. Existing exposure situation A situation of exposure that already exists when a decision on the need for control needs to be taken. Exposure The state or condition of being subject to irradiation. Exposure pathway A route by which radiation or radionuclides can reach humans and cause exposure. Facility This shall include a nuclear facility; installation where a radiation source is used; mining and raw materials processing facilities, such as uranium mines; radioactive waste management fa- cilities; and any other locations where radioactive materials are produced, processed, used, handled, stored or disposed of to the extent warranted by safety and security. Graded approach For a system of control a process or method in which the stringency of the control measures and conditions to be applied is commensurate, to the extent practicable, with the likelihood and possible consequences of, and the level of risk associated with, a loss of control. Health professional An individual who has been formally recognized through appropriate national procedures to practice a profession related to health (e.g. medicine, dentistry, chiropractic, podiatry, nurs- ing, medical physics, medical radiation technology, radiopharmacy, occupational health). Health screening program A program in which health tests or medical examinations are performed for the purpose of early detection of disease. 13 Radiation Safety – NRRC-R-01 Human factors Engineering in which factors that could influence human performance and that could affect safety are understood and are taken into account, especially in the design and operation of facilities. Individual monitoring Monitoring using measurements by equipment worn by individuals, or measurements of quantities of radioactive substances in or on, or taken into, the bodies of individuals, or meas- urements of quantities of radioactive substances excreted from the body by individuals. Inspection imaging device An imaging device designed specifically for imaging persons or cargo conveyances to detect concealed objects on or within the human body or within cargo or a vehicle. Intake 1. The act or process of taking radionuclides into the body by inhalation or ingestion or through the skin. 2. The activity (A) of a radionuclide taken into the body in a given period or as a result of a given event. Investigation level The value of a quantity such as effective dose, intake or contamination per unit area or volume at or above which an investigation would be conducted. Justification 1. Justification for a planned exposure situation The process of determining for a planned exposure situation whether a practice is, overall, beneficial, i.e. whether the expected benefits to individuals and to society from introducing or continuing the practice outweigh the harm (including radiation detriment) resulting from the practice. 2. Justification for a existing or emergency situation The process of determining for an emergency exposure situation or an existing exposure situ- ation whether a proposed protective action or remedial action is likely, overall, to be benefi- cial; i.e., whether the expected benefits to individuals and to society (including the reduction in radiation detriment) from introducing or continuing the protective action or remedial action outweigh the cost of such action and any harm or damage caused by the action. Limit The value of a quantity used in certain specified activities or circumstances that must not be exceeded. 14 Radiation Safety – NRRC-R-01 Management system A set of interrelated or interacting elements (system) for establishing policies and objectives and enabling the objectives to be achieved in an efficient and an effective manner. Medical exposure Exposure incurred by patients for the purposes of medical or dental diagnosis or treatment; by carers and comforters; and by volunteers subject to exposure as part of a program of bio- medical research. Medical physicist A Health professional recognized by the competent authority of the Kingdom. Medical radiation facility A medical facility in which radiological procedures are performed. Medical radiation technologist A health professional, with specialist education and training in medical radiation technology, competent to perform radiological procedures, on delegation from the radiological medical practitioner, in one or more of the specialties of medical radiation technology. Medical radiological equipment Radiological equipment used in medical radiation facilities to perform radiological procedures that either delivers an exposure of an individual or directly controls or influences the extent of such exposure. The term applies to radiation generators, such as X ray machines or medical linear accelerators; to devices containing sealed sources, such as 60Co teletherapy units; to devices used in medical imaging to capture images, such as gamma cameras, image intensifiers or flat panel detectors, and to hybrid systems such as positron emission tomography-com- puted tomography scanners. Member of the public For purposes of protection and safety, in a general sense, any individual in the population except when subject to occupational exposure or medical exposure. For the purpose of veri- fying compliance with the annual dose limit for public exposure, this is the representative per- son. Monitoring The measurement of dose, dose rate or activity (A) for reasons relating to the assessment or control of exposure to radiation or exposure due to radioactive substances, and the interpre- tation of the results. 15 Radiation Safety – NRRC-R-01 Natural background The doses, dose rates or activity (A) concentrations associated with natural sources, or any other sources in the environment that are not amenable to control. Natural source A naturally occurring source of radiation, such as the sun and stars (sources of cosmic radia- tion) and rocks and soil (terrestrial sources of radiation), or any other material whose radioac- tivity is for all intents and purposes due only to radionuclides of natural origin, such as products or residues from the processing of minerals; but excluding radioactive material for use in a nuclear installation and radioactive waste generated in a nuclear installation. Notification A document submitted to the NRRC by a person intending to carry out any activity or practice or to establish a radiation facility involving radiation sources. Nuclear fuel cycle All operations associated with the production of nuclear energy. These include: (a) Mining and processing of uranium ores or thorium ores; (b) Enrichment of uranium; (c) Manufacture of nuclear fuel; (d) Operation of nuclear reactors (including research reactors); (e) Reprocessing of spent fuel; (f) All waste management activities (including decommissioning) relating to operations associated with the production of nuclear energy; (g) Any related research and development activities. Nuclear installation Any nuclear facility subject to authorization that is part of the nuclear fuel cycle, except facili- ties for the mining or processing of uranium ores or thorium ores and radioactive waste dis- posal facilities. Nuclear or radiological emergency Any emergency, which results or is likely to result in exposure risk to ionizing radiation Occupational exposure Exposure of workers incurred in the course of their work. Operational limits and conditions A set of rules setting forth parameter limits, the functional capability and the performance levels of equipment and personnel approved by the NRRC for safe operation of an authorized facility. 16 Radiation Safety – NRRC-R-01 Optimization of protection and safety The process of determining what level of protection and safety would result in the magnitude of individual doses, the number of individuals (workers and members of the public) subject to exposure and the likelihood of exposure being “as low as reasonably achievable, economic and social factors being taken into account” (ALARA). For medical exposures of patients, the optimization of protection and safety is the management of the radiation dose to the patient commensurate with the medical purpose. Planned exposure situation The situation of exposure that arises from the planned operation of a source or from a planned activity that results in an exposure due to a source. Planning target volume A geometrical concept used in radiation therapy for planning medical treatment with consid- eration of the net effect of movements of the patient and of the tissues to be irradiated, vari- ations in size and shape of the tissues, and variations in beam geometry such as beam size and beam direction. Potential exposure Prospectively considered exposure that is not expected to be delivered with certainty but that may result from an anticipated operational occurrence or accident at a source or owing to an event or sequence of events of a probabilistic nature, including equipment failures and oper- ating errors. Practice Any human activity that causes or is likely to cause exposure to ionizing radiation, excluding procedures of medical diagnosis or treatment of patients by healthcare practitioners. Projected dose The dose that would be expected to be received if planned protective actions were not taken. Protection (against radiation) See Radiation Protection. Protection and safety The protection of people against exposure to ionizing radiation or exposure due to radioactive material and the safety of sources, including the means for achieving this, and the means for preventing accidents and for mitigating the consequences of accidents if they do occur. 17 Radiation Safety – NRRC-R-01 Protective action An action for the purposes of avoiding or reducing doses that might otherwise be received in an emergency exposure situation or an existing exposure situation. Providers of consumer products Designers, manufacturers, producers, constructors, installers, distributors, sellers, and import- ers and exporters of consumer products. Public exposure Exposure incurred by members of the public due to sources in planned exposure situations, emergency exposure situations and existing exposure situations, excluding any occupational exposure or medical exposure. Qualified expert An individual who is duly recognized as having expertise in a relevant field of specialization, e.g. medical physics, radiation protection, occupational health, fire safety, quality manage- ment or any relevant engineering or safety specialty. Quality assurance The function of a management system that provides confidence that specified requirements will be fulfilled. Radiation The ionizing radiation as defined in the Law. Radiation detriment The total harm that would eventually be incurred by a group that is subject to exposure and by its descendants as a result of the group’s exposure to radiation from a source. Radiation generator A device capable of generating ionizing radiation, such as X ray𝑠𝑠, neutrons, electrons or other charged particles, that may be used for scientific, industrial or medical purposes. Radiation protection The protection of people from the harmful effects of exposure to ionizing radiation and the means for achieving this. Radiation source Any radiation generator, radioactive source, or any other radioactive material outside the nu- clear fuel cycles of research and power reactors. 18 Radiation Safety – NRRC-R-01 Radiation safety officer (RSO) A competent person certified by the NRRC in radiation safety matters relevant for a given type of practice who is designated by the authorized person or employer to oversee the application of regulatory requirements. Radiation protection program Systematic arrangements that are aimed at providing adequate consideration of radiation pro- tection measures. Radiation risks Detrimental health effects of exposure to radiation (including the likelihood of such effects occurring), and any other safety related risks (including those to the environment) that might arise as a direct consequence of: (a) Exposure to radiation; (b) The presence of radioactive material (including radioactive waste) or its release to the environment; (c) A loss of control over a nuclear reactor core, nuclear chain reaction, radioactive source or any other source of radiation. Radiation weighting factor, 𝒘𝒘𝑹𝑹 A number by which the absorbed dose in a tissue or organ is multiplied to reflect the relative biological effectiveness of the radiation in inducing stochastic effects at low doses, the result being the equivalent dose. The radiation weighting factor values* are: Type of radiation 𝒘𝒘𝐑𝐑 Photons 1 Electrons and muons 1 Protons and charged pions 2 Alpha particles, fission fragments, heavy ions 20 Neutrons A continuous function of neutron energy: 𝒘𝒘𝐑𝐑 = −[ln(𝐸𝐸𝑛𝑛 )]2 /6 2,5 + 18,2𝑒𝑒 𝐸𝐸𝑛𝑛 < 1 𝑀𝑀𝑀𝑀𝑀𝑀 5,0 + 17𝑒𝑒 −[ln(2𝐸𝐸𝑛𝑛 )]2 /6 1 𝑀𝑀𝑀𝑀𝑀𝑀 ≤ 𝐸𝐸𝑛𝑛 ≤ 50𝑀𝑀𝑀𝑀𝑀𝑀 −[ln(0 04𝐸𝐸𝑛𝑛 )]2 /6 2,5 + 3,25𝑒𝑒 𝐸𝐸𝑛𝑛 > 50 𝑀𝑀𝑀𝑀𝑀𝑀 Note: All values relate to radiation incident on the body or, for internal radiation sources, radiation emitted from the incorporated radionuclide(s). 19 Radiation Safety – NRRC-R-01 * INTERNATIONAL COMMISSION ON RADIOLOGICAL PROTECTION, The 2007 Recommendations of the International Commission on Radiological Protection, Publication 103, Elsevier (2007). Radioactive material Any material from which ionizing radiation is emitted, whether spontaneously or within other equipment, and which is designated as subject to the control of the NRRC, including naturally occurring radioactive materials. Radioactive Source Any radioactive material permanently sealed in a capsule or closely bonded and in a solid form. Radioactive substance Any substance that contains radioactivity, and gives no indication of the magnitude of the haz- ard involved that may be designated by the NRRC as being subject to regulatory control. Radioactive waste Any material, regardless of its physical form, resulting from activities, practices or interven- tions such as decontamination, for which no further use is foreseen and which contains or is contaminated with radioactive substances, and has radiological activity (A) or concentration higher than the level set for clearance from regulatory control. Radioactive waste management All administrative and operational activities involved in the handling, pretreatment, treat- ment, conditioning, transport, storage and disposal of radioactive waste. Radiological medical practitioner A health professional with Specialist in education and training in the medical uses of radiation, who is competent to perform independently or to oversee radiological procedures in a given specialty. Radiological procedure A medical imaging procedure or therapeutic procedure that involves ionizing radiation, such as a procedure in diagnostic radiology, nuclear medicine or radiation therapy, or a planning procedure, image guided interventional procedure or other interventional procedure involv- ing radiation delivered by a radiation generator, a device containing a sealed source or an unsealed source, or by means of a radiopharmaceutical administered to a patient. Radionuclides of natural origin Radionuclides that occur naturally on Earth in significant quantities. 20 Radiation Safety – NRRC-R-01 Radiopharmacist A health professional, with Specialist in Education and training in radiopharmacy, who is com- petent to prepare and dispense radiopharmaceuticals used for the purposes of medical diag- nosis and radionuclide therapy. Reference level For an emergency exposure situation or an existing exposure situation, the level of risk or ac- tivity (A) concentration above which it is not appropriate to plan to allow exposures to occur and below which optimization of protection and safety would continue to be implemented. Referring medical practitioner A health professional who, in accordance with national requirements, may refer individuals to a radiological medical practitioner for medical exposure. Regulatory control Any form of control or regulation applied to activities and facilities including practices by the NRRC for reasons relating to nuclear safety and radiation protection or nuclear security or safeguards. Relative biological effectiveness (RBE) A relative measure of the effectiveness of different radiation types at inducing a specified health effect expressed as the inverse ratio of the absorbed doses of two different radiation types that would produce the same degree of a defined biological endpoint. Relative biological effectiveness (RBE) weighted absorbed dose, 𝑨𝑨𝑨𝑨𝑻𝑻 The quantity ADT,R , defined as: ADT,R = 𝐷𝐷T,R × RBET,R where 𝐷𝐷T,R is the absorbed dose delivered by radiation of type R averaged over a tissue or organ T and RBET,R is the relative biological effectiveness for radiation of type R in the pro- duction of severe deterministic effects in a tissue or organ T. When the radiation field is composed of different radiation types with different values of RBET,R the RBE weighted absorbed dose is given by: ADT = 𝐷𝐷T,R × RBET,R R Remedial action The removal of a source or the reduction of its magnitude (in terms of activity (A) or amount) for the purposes of preventing or reducing exposures that might otherwise occur in an existing exposure situation. 21 Radiation Safety – NRRC-R-01 Remediation Any measures that may be carried out to reduce the radiation exposure due to existing con- tamination of land areas through actions applied to the contamination itself (the source) or to the exposure pathways to humans. Representative person An individual receiving a dose that is representative of the doses to the more highly exposed individuals in the population. Response organization An organization designated or otherwise recognized by the Kingdom as being responsible for managing or implementing any aspect of an emergency response. Risk A multiattribute quantity expressing hazard, danger or chance of harmful or injurious conse- quences associated with exposures or potential exposure. It relates to quantities such as the probability that specific deleterious consequences may arise and the magnitude and character of such consequences. Safety assessment Assessment of all aspects of an activity that are relevant to protection and safety; for an au- thorized facility. This includes siting, design and operation of the facility. Safety culture The assembly of characteristics and attitudes in organizations and individuals which estab- lishes that, as an overriding priority, protection and safety issues receive the attention war- ranted by their significance. Safety measure Any action that might be taken, a condition that might be applied or procedure that might be followed to fulfill the requirements of Safety Requirements. Scenario A postulated or assumed set of conditions and/or events. Security Prevention and detection of any theft, sabotage, unauthorized access, illegal transfer (or any other criminal act) involving nuclear, nuclear-related or radioactive materials and associated facilities. 22 Radiation Safety – NRRC-R-01 Source Anything that may cause radiation exposure such as by emitting ionizing radiation or by re- leasing radioactive substances or radioactive material and can be treated as a single entity for purposes of protection and safety. Sealed source Radioactive source in which the radioactive material is permanently sealed in a capsule or closely bonded and in a solid form. Source monitoring The measurement of activity (A) in radioactive material being released to the environment or of external dose rates due to sources within an activity or a facility. Standards dosimetry laboratory A laboratory, designated by the NRRC that possesses the recognition necessary for the pur- pose of developing, maintaining or improving primary or secondary standards for radiation dosimetry. Storage The holding of radioactive sources, radioactive material, spent fuel or radioactive waste in a facility that provides for their/its containment, with the intention of retrieval. Structures, systems and components A general term encompassing all of the elements (items) of an activity or a facility that con- tribute to protection and safety, except human factors. Supervised area A defined area not designated as a controlled area but for which occupational exposure con- ditions are kept under review, even though specific protection measures or safety provisions are not normally needed. Supplier (of a source) Any person to whom the authorized person assigns duties, totally or partially, in relation to the design, manufacture, production or construction of a source. Technical Services Organizations An organization that provide expertise and services to support nuclear and radiation safety and all related scientific and technical issue. 23 Radiation Safety – NRRC-R-01 Tissue weighting factor, 𝒘𝒘𝑻𝑻 The multiplier of the equivalent dose to a tissue or organ used for purposes of radiation pro- tection to account for the different sensitivities of different tissues or organs to the induction of stochastic effects of radiation. Transport All operations and conditions associated with the movement of nuclear and radioactive mate- rial, whether through, from or into the territory of the Kingdom. Unsealed source A radioactive source in which the radioactive material is neither (a) permanently sealed in a capsule nor (b) closely bonded and in a solid form. Worker Any person who works, whether full time, part-time or temporarily, for an employer and who has recognized rights and duties in relation to occupational radiation protection. Workers’ health surveillance Medical supervision intended to ensure the initial and continuing fitness of workers for their intended tasks. Workplace monitoring Monitoring using measurements made in the working environment. 24 Radiation Safety – NRRC-R-01 Chapter 2: General Requirement on the Application of System of Protection Justification 9. Not any practice that alters or could alerts the radiation exposure situation by introducing a new radiation source, by reducing existing exposure or by reducing the risk of potential exposure shall be engaged in unless such practice yields a benefit to all persons exposed to radiation or the community as a whole which justifies the radiation harm that it might cause, taking into account social, economic and other relevant factors. 10. The following practices are deemed to be not justified, unless the applicant demonstrates, by a due process, that concerned practice meet general justification criteria as in Article 9 above: (a) The practices whose implementation would result in increasing the volume of the radioactive substance (through addition or activation) in the commodities or products are considered among not justified practices. Such practices shall include the following: (i) Fabrication, production, importation or sales of foodstuffs, drinks or other products intended for ingestion, inhalation or penetration of the skin or use by humans in gen- eral. (ii) Utilization of radioactive substances in the products or commodities. (b) Human imaging using radiation that is performed as a form of art or for publicity purposes; (c) Human imaging using radiation that is performed for occupational, legal or health insurance purposes, and is undertaken without reference to clinical indication; (d) Human imaging using radiation for theft detection purposes; (e) Human imaging using radiation for the detection of concealed objects for anti-smuggling purposes; (f) Human imaging using radiation for the detection of concealed objects that can be used for criminal acts or to pose a national security threat; (g) Other activities and practices as determine by the NRRC. Demonstration of the justification of practices 11. Any person intending to conduct a practice shall demonstrate the justification when: (a) The practice has not been previously considered as justified. (b) The NRRC requests for reviewing the existing type of practice in the light of new information about its efficacy or consequences. (c) The concerned practice is one of those mentioned in Section 5, that are deemed to be not justified. 12. The demonstration of justification shall include: 25 Radiation Safety – NRRC-R-01 (a) A description of the type of practice. (b) A full characterization of the radiation sources that will be used and the measures that will be taken to ensure safety and to reduce the radiological consequences. (c) An appraisal of the benefits and detriments, including radiation detriments. This appraisal should include economic, social, health and safety, waste management, recycling, radiologi- cal environmental impact and decommissioning aspects. The assessment of the radiation detriment should cover both the magnitude and the likelihood of expected exposures and an assessment of the potential exposures. (d) An indication of the expected extent of use of the type of practice. 13. In the case of practices involving the deliberate exposure of humans for non-medical imaging pur- poses, when evaluating the justification of the concerned practice, considerations listed in Section 40 shall be taken into account. 14. The demonstration of justification by the applicant, if required, is part of the authorization process referenced in Sections 21 and 22. Optimization of Protection and Safety 15. The authorized person and any other responsible person shall ensure that the system of protection implemented over activities and facilities under its responsibility guarantees the application of: (a) Measures for protection that are optimized for the prevailing circumstances, with account taken of the available options for protection and safety as well as the nature, likelihood and magnitude of exposures; (b) Measures, on the basis of the results of the optimization, for the restriction of the likelihood and magnitudes of exposures by means of measures for preventing radiation safety devia- tions and for mitigating the consequences of those that do occur; (c) Dose constraints for occupational and public exposure. 16. For occupational exposure and public exposure, the authorized person and any other responsible person shall ensure that the magnitude of individual doses, the likelihood of exposure and the num- ber of individuals exposed are kept as low as reasonably achievable, taking economic and societal factors into account. 17. For the protection of individuals subject to medical exposure, the authorized person and any other responsible person shall ensure that medical exposure is limited to what is necessary to achieve the intended examination or treatment result and performance of the procedure. 18. Measures for the optimization of the protection and safety shall be re-evaluated, by the authorized person on a periodical and timely basis or at any time deem necessary as determine by the NRRC. Dose Constraints 19. The authorized person shall establish dose constraints, as appropriate according to the category of exposure individuals to be approved by the NRRC for the following types of exposure: (a) Occupational and public exposures - Where relevant, the doses constraints shall be estab- lished in co-operation with the employer of the outside worker. 26 Radiation Safety – NRRC-R-01 (b) Medical exposure - Dose constraints shall apply only with regard to the protection of carers and comforters and volunteers participating in medical or biomedical research. 20. The authorized person shall ensure that the dose constraints are: (a) Established in terms of individual effective or equivalent doses over a defined appropriate time period. (b) Remained below the generic values defined by the NRRC for similar types of practices. (c) Established so that the prospective annual doses to members of the public, including people distant from the source and people of future generations, summed over all exposure path- ways, including contributions by other practices and sources, are unlikely to exceed the dose limits for the public or any lower values established by the NRRC for any source that can release radioactive material to the environment. Reference Levels 21. Any person that are involved in any activity concerning emergency or existing exposure situations shall use the relevant References Levels, established by the NRRC, as a boundary condition in identi- fying the range of options for optimization in implementing protective actions. Dose Limits 22. In planned exposure situations, the authorized person shall ensure that the exposures of individuals due to the activities and practices for which they are authorized are restricted so that the following relevant dose limits: (a) For occupational exposure of worker over the age of 18 years: (i) An effective dose of 20 mSv per year averaged over five consecutive years (100 mSv in 5 years) and of 50 mSv in any single year; (ii) An equivalent dose to the lens of the eye of 20 mSv per year averaged over five con- secutive years (100 mSv in 5 years) and of 50 mSv in any single year; (iii) An equivalent dose to the extremities (hands and feet) or the skin of 500 mSv in a year. (b) For occupational exposure of apprentices of 16 to 18 years of age who are being trained for employment involving radiation and for exposure of students of age 16 to 18 who use sources in the course of their studies: (i) An effective dose of 6 mSv in a year; (ii) An equivalent dose to the lens of the eye of 20 mSv in a year; (iii) An equivalent dose to the extremities (hands and feet) or to the skin of 150 mSv in a year. 23. For a female worker who has notified pregnancy or is breast-feeding, the expected dose for the em- bryo or fetus or the breastfed infant shall be limited to 1 mSv. 24. For public exposure, the dose limits shall be: 27 Radiation Safety – NRRC-R-01 (a) An effective dose of 1 mSv in a year; (b) In special circumstances, a higher value of effective dose in a single year could apply, pro- vided that the average effective dose over five consecutive years does not exceed 1 mSv per year; (c) An equivalent dose to the lens of the eye of 15 mSv in a year; (d) An equivalent dose to the skin of 50 mSv in a year. 25. The verification of compliance with the dose limit shall consider the criteria, conversion factors and other references values specified by the NRRC which allow to get the best estimation of the quanti- ties used for controlling the dose limits. 26. Whenever the NRRC deems necessary to revise the established dose limits the authorized person shall implement all the necessary corrective actions to ensure compliance with the revised dose adopted limits. Chapter 3: Responsibilities for Protection and Safety General Responsibilities 27. The authorized person or any responsible person for the activity or at the facility, shall have the prime responsibility for protection and safety, which cannot be delegated. 28. Any responsible person for the management of an existing exposure situation or involved in the emergency situation shall have specified responsibilities for the application of relevant requirements specified in this regulation. 29. The authorized person and any other person accountable for any practices shall be responsible for: (a) Establishing a radiation protection program that is appropriate for exposure situation that: (i) Adopt objectives for protection and safety in accordance with the requirements of this regulation; (ii) Apply measures for protection and safety that are commensurate with the radiation risks associated with the exposure situation that ensures compliance with the re- quirements of this regulation. (b) Implementation of the radiation protection program that ensures: (i) Measures and resources necessary for achieving the objectives for protection and safety have been determined and are duly provided; (ii) Program that is periodically reviewed to assess its effectiveness and its continued fitness for purpose; (iii) Any failures or shortcomings in protection and safety that are identified and cor- rected, and steps are taken to prevent their recurrence; (iv) Any concern that is related to radiation protection and safety are addressed; (v) Appropriate records are maintained. 28 Radiation Safety – NRRC-R-01 30. The authorized person and any other person having responsibilities in relation to protection and safety shall ensure that all personnel engaged in activities relevant to protection and safety have appropriate education, training and qualification, so that they understand their responsibilities and able to perform their duties competently, with appropriate judgment and in accordance with the approved procedures. Management System 31. The authorized person and any other person having responsibilities in relation to protection and safety, shall ensure that protection and safety are effectively integrated into the overall management system of the organizations for which they are responsible. 32. The authorized person and any other person accountable for the operation of the facility shall demonstrate commitment to protection and safety at the highest levels within the organizations for which they are responsible for. 33. The management system shall be designed and applied to enhance protection and safety that: (a) Applies the requirements for protection and safety coherently with other requirements; (b) Describes the planned and systematic actions necessary to provide adequate confidence that the requirements for protection and safety are fulfilled; (c) Ensures protection and safety are not compromised by other requirements; (d) Provides for the regular assessment of performance for protection and safety, and the appli- cation of lessons learned from experience; (e) Promotes safety culture; (f) Establishes clear lines of responsibility, authority for decisions on safety and accountability for protection and safety for the sources for which they are authorized; (g) Ensures that problems affecting protection and safety are promptly identified and corrected in a manner commensurate with their importance; (h) Establishes organizational arrangements and lines of communications that result in an ap- propriate flow of information on safety at and between the various levels in the entire or- ganization of the authorized person. 34. The protection and safety elements of the management system shall commensurate with the com- plexity and the radiation risks associated with the activity. 35. The authorized person shall establish procedures for reporting on and learning from accidents and other incidents. Safety Culture 36. The authorized person and any other person having responsibilities in relation to protection and safety shall promote and maintain a safety culture through: (a) Inculcating individual and collective commitment to protection and safety at all levels of the organization; 29 Radiation Safety – NRRC-R-01 (b) Ensuring a common understanding of the key aspects of safety culture within the organiza- tion; (c) Providing the means by which the organization supports individuals and teams in carrying out their tasks safely and successfully, with account taken of the interactions between indi- viduals, technology and the organization; (d) Encouraging the participation of workers and their representatives and other relevant per- sons in the development and implementation of policies, rules and procedures dealing with protection and safety; (e) Ensuring accountability of the organization and of individuals at all levels for protection and safety; (f) Encouraging open communication with regard to protection and safety within the organiza- tion and with relevant parties, as appropriate; (g) Encouraging a questioning and learning attitude and discouraging complacency with regard to protection and safety; (h) Providing means by which the organization continually seeks to develop and strengthen its safety culture. Human Factors 37. The authorized person and any other person accountable for the operation of the facility, shall take into account human factors, support good performance and good practices to prevent human and organizational failures. 38. Sound ergonomic principles in the design of equipment and the development of operating proce- dures shall be ensured to: (a) Facilitate the safe operation and use of equipment; (b) Minimize the possibility of operator error that could lead to accidents; and (c) Reduce the possibility that indications of normal conditions and abnormal conditions to be misinterpreted. 39. Appropriate equipment, safety systems and procedural requirements shall be provided to: (a) Reduce, as far as practicable, the possibility that human errors or inadvertent actions that could give rise to accidents or to other incidents leading to the exposure of any person; (b) Provide means for detecting human errors and for correcting them or compensating for them; and (c) Facilitate protective actions and corrective actions in the event of failures of safety systems or failures of measures for protection and safety. 30 Radiation Safety – NRRC-R-01 Chapter 4: Bases of Protection in Planned Exposure Situations General Requirement 40. Radiation protection shall be ensured for any activity and facility authorized by the NRRC. 41. No person shall adopt, introduce, conduct, discontinue or cease a practice, unless the requirements of this regulation, including requirements of notification and authorization, are met. 42. No person shall conduct any activity or practice with radiation source other than in accordance with the requirements of this regulation. 43. The control over any radiation sources within any activity and facility authorized by the NRRC shall be ensured by the authorized person. 44. Any responsible person at facility with existing exposure situations, as specified in Article 287, which are of concern from a radiation protection point of view shall be subject to regulatory control and planned exposure situations requirements. Categorization of Sealed Sources 45. The categorization of sealed sources as specified in Appendix 1 shall be used for the purpose of applying a graded approach for radiation protection prescribed in this regulation. Prohibition of Practices 46. Practices that deem to be not justified, taking into account principles provided in Section 5, shall be prohibited. Requirements for Notification 47. Unless exempt from requirements in accordance with Section 19, any person: (a) Who, on the effective date of the publication of this regulation, is responsible for an activity, a facility or a practice involving radiation source, shall immediately submit a notification to the NRRC. (b) Who intends to initiate an activity, a facility or a practice shall submit a prior notification to the NRRC of such an intention or to apply for an authorization. 48. Notwithstanding the exemption criteria prescribed in Section 19, in situations where there is concern that a practice involving naturally occurring radioactive material may lead to the presence of such radionuclides in water liable to affect the quality of drinking water supplies or affect any other expo- sure pathways, so as to be of concern from a radiation protection point of view, the person respon- sible for such practice shall submit a notification to the NRRC. 49. For those activities where an application for an authorization is submitted, no separate notification shall be required. 50. After submission of notification, any person who is required to apply to the NRRC for an authorization and who submits such an application in accordance with Section 22 is permitted to continue existing activities specified in the notification, in conformance with the applicable requirements of this Reg- ulation, until the NRRC revokes such permission or grants the authorization. 31 Radiation Safety – NRRC-R-01 Exemption of Practices and Sources 51. The activities involving the following radiation sources are automatically exempted from require- ments of this regulation, including the requirements for notification and authorization with prior evaluation: (a) Radioactive materials in quantities not greater than one tonne for which either the total ac- tivity (A) of a given nuclide present on the premises at any one time or its activity (A) con- centration does not exceed the levels specified by NRRC. (b) Radioactive materials in quantities greater than one tonne for which the activity (A) concen- tration of a given radionuclide of artificial origin used in the practice does not exceed the levels specified by NRRC. (c) Equipment containing radioactive material exceeding the quantities or concentrations spec- ified in Article 51(a), provided that: (i) The equipment containing radioactive material is of a type approved by the NRRC. (ii) Where the radioactive material is in the form of a sealed source the safety features of the equipment effectively prevent any contact with the radioactive material and prevent its leakage. (iii) Where the radioactive material is in the form of an unsealed source the total amount of involved activity (A) shall be as small as those used for radioimmunoassay. (iv) In normal operating conditions the equipment does not cause an ambient dose equivalent rate or a directional dose equivalent rate, as appropriate, exceeding 1 μSv/h at a distance of 0.1 m from any accessible surface of the apparatus. (v) Necessary conditions for later management of the equipment have been specified by the NRRC. (d) Radiation generators of a type approved by the NRRC, or in the form of an electronic tube, provided that: (i) They do not in normal operating conditions cause an ambient dose equivalent rate or a directional dose equivalent rate, as appropriate, exceeding 1 μSv/h at a distance of 0.1 m from any accessible surface of the equipment; or (ii) The maximum energy of the radiation generated is no greater than 5 keV or as spec- ified by the NRRC 52. The practices involving the following radiation sources are exempted from requirements of this Reg- ulation, including the requirements for notification and authorization with prior evaluation: (a) A practice in which the radioactive substance derives from discharges of radioactive sub- stances permitted in accordance with Section 102; (b) A practice in which the radioactive substance derives from material that has been cleared for reuse, recycling or disposal in accordance with Section 103; (c) The use of building materials when the activity (A) concentration of the relevant natural ra- dionuclides is not liable to give doses exceeding the reference level defined by the NRRC. 32 Radiation Safety – NRRC-R-01 Exemption Under a Decision by the NRRC 53. Exemptions shall not be granted for practices deemed not to be justified as specified in Sections 5. 54. The NRRC may exempt a practice or a source within a practice from the authorization or any other requirement of this regulation provided that the practice is justified and the following general criteria are met: (a) Radiation risks arising from the practice or from a source within the practice are sufficiently low as not to warrant regulatory control, with no appreciable likelihood of situations arising that could lead to a failure to meet the general criterion for exemption; or (b) Regulatory control of the practice or the source would yield no net benefit, in that no rea- sonable measures for regulatory control would achieve a worthwhile return in terms of re- duction of individual doses or of health risks. 55. The NRRC may exempt a practice or a source within a practice from any requirement of this regula- tion provided that: (a) The effective dose expected to be incurred by any in