Chapter 24: Radiation Protection
Chapter 24: Radiation ProtectionSlide set of 172 slides based on the chapter authored byD. Sutton, L.T. Collins and J. Le Heronof the IAEA publication (ISBN 978-92-0-131010-1):Diagnostic Radiology Physics:A Handbook for Teachers and StudentsObjective:To familiarize students with the systems of radiation protectionused in diagnostic radiology.Slide set preparedby E.Okuno (S. Paulo, Brazil,Institute of Physics of S. Paulo University)IAEAInternational Atomic Energy Agency
Chapter 24. TABLE OF CONTENTS24.1. Introduction24.2. The ICRP system of radiological protection24.3. Implementation of Radiation Protection inthe Radiology Facility24.4. Medical exposures24.5. Occupational exposure24.6. Public exposure in radiology practices24.7. ShieldingIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 2
24.1. INTRODUCTION Basic radiation biology and radiation effectsdemonstrate the need to have a system of radiationprotection which allows the many beneficial uses ofradiation while ensuring detrimental radiation effectsare either prevented or minimized This can be achieved with the twin objectives of:preventing the occurrence of deterministic effectslimiting the probability of stochastic effects to alevel that is considered acceptableIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 3
24.1. INTRODUCTIONIn a radiology facility, consideration needs to be given to the: patient staff involved in performing the radiological procedures members of the public other staff that may be in the radiology facility, carers andcomforters of patients undergoing procedures, and persons whomay be undergoing a radiological procedure as part of abiomedical research projectThis chapter discusses how the objectives given above are reachedthrough a system of radiation protection and how such a system shouldbe applied practically in a radiology facilityIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 4
24.2. THE ICRP SYSTEM OF RADIOLOGICAL PROTECTION The means for achieving the objectives of radiationprotection have evolved to the point where there isconsensus on a System of Radiological Protection under theauspices of the International Commission of RadiologicalProtection (ICRP) The detailed formulation of the system and its principles can befound in the ICRP publications and they cannot easily beparaphrased without losing their essence A brief, although simplified, summary is given here, especially as itapplies to diagnostic radiology and image-guided interventionalproceduresIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 5
24.2. THE ICRP SYSTEM OF RADIOLOGICAL PROTECTION24.2.1. Situations, types and categories of exposureThe ICRP Publication 103 divides all possible situationswhere radiological exposure can occur into three types: planned exposure situationsin radiology emergency exposure situations existing exposure situationsThe use of radiation in radiology is a planned exposureIt must be under regulatory control, with an appropriateauthorization in place from the regulatory body before operationcan commenceIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 6
24.2. THE ICRP SYSTEM OF RADIOLOGICAL PROTECTION24.2.1. Situations, types and categories of exposure Normal exposures: occur in the daily operation of a radiology facilitywith reasonably predictable magnitudes Potential exposures: are unintended exposures or accidents. Theseexposures remain part of the planned exposure situation as theirpossible occurrence is considered in the granting of an authorizationThe ICRP then divides exposure of individuals (both normal andpotential) into three categories : occupational exposure public exposure medical exposureAll three exposure categories need to be considered in the radiologyfacilityIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 7
24.2. THE ICRP SYSTEM OF RADIOLOGICAL PROTECTION24.2.1.1. Occupational exposureDefined by the ICRP as: Radiation exposures of workers incurredas a result of their work, in situationswhich can reasonably be regarded aswithin the responsibility of the employingor operating managementIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 8
24.2. THE ICRP SYSTEM OF RADIOLOGICAL PROTECTION24.2.1.2. Public exposure Includes all public exposures other than occupationalor medical exposures, and covers a wide range ofsources of which natural sources are by far the largestPublic exposure in a radiology facility would includeexposure: to persons who may happen to be close to or withinthe facility and potentially subject to radiationpenetrating the walls of an X ray room of the embryo and foetus or pregnant workersIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 9
24.2. THE ICRP SYSTEM OF RADIOLOGICAL PROTECTION24.2.1.3. Medical exposureMedical exposure is divided into three components: patient exposure biomedical research exposure carers and comforters exposureAn individual person may be subject to one or more ofthese categories of exposure, but for radiationprotection purposes each is dealt with separatelyIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 10
24.2. THE ICRP SYSTEM OF RADIOLOGICAL PROTECTION24.2.1.3. Medical exposure Medical exposures are intentional exposures for the diagnostic ortherapeutic benefit of the patient They are a very significant and increasing source of exposure Advanced countries have shown an increase of 58 % in diagnosticexposures between the UNSCEAR 2000 and 2008 CT was by far the greatest contributor, being 7.9 % of examinations,but 47 % of dose For the whole world population, the annual effective dose per personfrom medical sources is 0.62 mSv compared to 2.4 mSv for naturalsources This rapid growth emphasises the need for effective implementationof the radiation protection principles of justification and optimizationIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 11
24.2. THE ICRP SYSTEM OF RADIOLOGICAL PROTECTION24.2.2. Basic framework of radiation protectionThe ICRP system of radiation protection has 3 fundamental principles: Justification: any decision that alters the radiation exposure situation should domore good than harm Optimization of protection: the likelihood of incurring exposures, the number ofpeople exposed, and the magnitude of their individual doses should all be keptas low as reasonably achievable, taking into account economic and societalfactors Limitation of doses: the total dose to any individual from regulated sources inplanned exposure situations other than medical exposure of patients should notexceed the appropriate limits recommended by the CommissionIn a radiology facility, occupational and public exposure is subject to all3 principles, whereas medical exposure is subject to the first two onlyIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 12
24.2. THE ICRP SYSTEM OF RADIOLOGICAL PROTECTION24.2.2. Basic framework of radiation protectionRecommended dose limits in planned exposure situationsa (ICRP 103)Type of limitEffective doseAnnual equivalent dose in:Lens of the eyebSkinc,dHands and feetOccupational20 mSv per year, averaged overdefined periods of 5 yearse20 mSv500 mSv500 mSvPublic1 mSv in a yearf15 mSv50 mSv–aLimits on effective dose are for the sum of the relevant effective doses from external exposure in thespecified time period and the committed effective dose from intakes of radionuclides in the same periodFor adults, the committed effective dose is computed for a 50-year period after intake, whereasfor children it is computed for the period up to age 70 yearsb this limit is a 2011 ICRP recommendationc The limitation on effective dose provides sufficient protection for the skin against stochastic effectsd Averaged over 1 cm 2 area of skin regardless of the area exposede With the further provision that the effective dose should not exceed 50 mSv in any single yearAdditional restrictions apply to the occupational exposure of pregnant womenf In special circumstances, a higher value of effective dose could be allowed in a single year, provided thatthe average over 5 years does not exceed 1 mSv per yearIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 13
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.1. IntroductionThe current version of the IAEA safety standard:“International Basic Safety Standards for Protection against IonizingRadiation and for the Safety of Radiation Sources” (the BSS) wasissued in 1996 under the joint sponsorship of the: Food and Agriculture Organization of the United Nations, IAEA, InternationalLabour Organisation, OECD Nuclear Energy Agency, Pan American HealthOrganization, World Health OrganizationThe BSS was published as IAEA Safety Series No. 115 and comprises foursections: preamble, principal requirements, appendices and schedulesThe purpose of the report is to establish basic requirements for protectionagainst exposure to ionizing radiation and for the safety of radiation sourcesthat may deliver such exposureIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 14
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.1. Introduction The requirements of the BSS underpin the implementation of radiationprotection in a radiology facility, supplemented by the relevant IAEASafety Guides and Safety Reports IAEA Safety Reports Series No. 39 covers:Diagnostic radiology and interventional procedures using X-raysAll IAEA publications are downloadable from the IAEA websiteThe International Commission on Radiological Protection (ICRP) hasaddressed recommendations for radiological protection and safety inmedicine specifically in Publications:IAEAICRP 73ICRP 103ICRP 105Diagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 15
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.2. Responsibilities Implementation of radiation protection in the hospital or medicalfacility must fit in with, and be complementary to, the systems forimplementing medical practice in the facility Radiation protection must not be seen as something imposed from“outside” and separate to the real business of providing medicalservices and patient care To achieve a high standard of radiation protection, it is veryimportant to establish a safety-based attitude in every individual suchthat protection and accident prevention are regarded as a natural partof the every-day dutyIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 16
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.2. Responsibilities This objective is primarily achieved by education and training andencouraging a questioning and learning attitude, but also by a positiveand cooperative attitude from the national authorities and the employerin supporting radiation protection with sufficient resources, both in termsof personnel and money Every individual should also know their responsibilities through formalassignment of duties For an effective radiation protection outcome, the efforts of variouscategories of personnel engaged in the medical use of ionizing radiationmust be coordinated and integrated, preferably by promoting teamwork,where every individual is well aware of their responsibilities and dutiesIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 17
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.3. Responsibilities of the licensee and employerThe licensee of the radiology facility, through the authorization issuedby the radiation protection regulatory body: has the prime responsibility for applying the relevant national regulations andmeeting the conditions of the licence bears the responsibility for setting up and implementing the technical andorganizational measures that are needed for ensuring radiation protectionand safety may appoint other people to carry out actions and tasks related to theseresponsibilities, but retains overall responsibilityIn particular, the radiological medical practitioner, the medical physicist, themedical radiation technologist and the radiation protection officer (RPO) allhave key roles and responsibilities in implementing radiation protection in theradiology facilityIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 18
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.3. Responsibilities of the licensee and employerWith respect to medical exposure, the licensee’s keyresponsibilities include ensuring that: the necessary personnel (radiological medical practitioners, medicalphysicists, and medical radiation technologists) are employed, and that theindividuals have the necessary education, training and competence toassume their assigned roles and to perform their respective duties no person receives a medical exposure unless there has been appropriatereferral, it is justified and the radiation protection has been optimized all practicable measures are taken to minimize the likelihood of unintendedor accidental medical exposures, and to promptly investigate any suchexposure, with the implementation of appropriate corrective actionsIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 19
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.3. Responsibilities of the licensee and employer Radiological medical practitioner is the generic term used in therevised BSS, and is defined as a health professional, with educationand specialist training in the medical uses of radiation, who iscompetent to independently perform or oversee procedures involvingmedical exposure in a given specialtyIn the radiology facility, a radiologist is the most common radiologicalmedical practitioner but many other medical specialists may also be inthis role, including, for example, interventional cardiologists, urologists,gastroenterologists, orthopaedic surgeons, dentists Medical radiation technologist is the generic term used in the revisedBSS to cover the various terms used throughout the world, such asradiographer and radiologic technologistIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 20
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.3. Responsibilities of the licensee and employerWith respect to occupational exposure, key responsibilities of theemployer and licensee include ensuring that: occupational radiation protection and safety is optimized and that thedose limits for occupational exposure are not exceeded a radiation protection programme is established and maintained,including local rules and provision of personal protective equipment arrangements are in place for the assessment of occupationalexposure through a personnel monitoring program adequate information, instruction and training on radiation protectionand safety are providedIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 21
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.3. Responsibilities of the licensee and employerThe licensee also has responsibility for radiationprotection of the public which includes ensuring that: there are restrictions in place to prevent unauthorisedaccess to functioning X ray rooms area monitoring is carried out to assure consistency withpublic exposure standards and that appropriate recordsare keptIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 22
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.4. Responsibilities of other partiesRadiological medical practitioner The general medical and health care of the patient is, of course,the responsibility of the individual physician treating the patient But when the patient presents in the radiology facility, theradiological medical practitioner has the particular responsibility forthe overall radiation protection of the patient This means responsibility for the justification of the givenradiological procedure for the patient, in conjunction with thereferring medical practitioner, and responsibility for ensuring theoptimization of protection in the performance of the examinationIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 23
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.4. Responsibilities of other partiesMedical physicist provides specialist expertise with respect to radiation protectionof the patient has responsibilities in the implementation of the optimization ofradiation protection in medical exposures, including calibrationof imaging equipment, image quality and patient doseassessment, and physical aspects of the quality assuranceprogramme, including medical radiological equipmentacceptance and commissioning in diagnostic radiology is also likely to have responsibilities in providing radiationprotection training for medical and health personnel may also perform the role of the RPO, with responsibilitiesprimarily in occupational and public radiation protectionIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 24
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.4. Responsibilities of other partiesMedical radiation technologist has a key role, and his/her skill and care in thechoice of techniques and parameters determine to alarge extent the practical realization of theoptimization of a given patient’s exposure in manymodalitiesIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 25
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.4. Responsibilities of other partiesRadiation protection officer (RPO) has responsibilities to oversee and implement radiation protectionmatters in the facility, but noting that specialist responsibilities forpatient radiation protection lie with the medical physicist might also be a medical physicistDuties of the RPO include: ensuring that all relevant regulations and licence conditions are followed assisting in the preparation and maintenance of radiation safety procedures(local rules) shielding design for the facility arranging appropriate monitoring procedures (individual and workplace) education and training of personnel in radiation protectionIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 26
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.4. Responsibilities of other partiesAll personnelNotwithstanding the responsibilities outlined above, allpersons working with radiation have responsibilities forradiation protection and safety: they must follow applicable rules and procedures use available protective equipment and clothing cooperate with personnel monitoring abstain from wilful actions that could result in unsafe practice undertake training as providedIAEADiagnostic Radiology Physics: a Handbook for Teachers and Students – chapter 24, 27
24.3. IMPLEMENTATION OF RADIATION PROTECTION INTHE RADIOLOGY FACILITY24.3.5. Radiation protection programmeThe BSS requires a licensee (and employer where appropriate) to: develop implement documenta protection and safety programme commensurate with the natureand extent of the risks of the practice to ensure compliance withradiation protection standardsSuch a programme is often called a radiation protectionprogr
Diagnostic Radiology Physics: a Handbook for Teachers and Students –chapter 24, 3 Basic radiation biology and radiation effects demonstrate the need to have a system of radiation protection which allows the many beneficial uses of radiation while ensurin
Part One: Heir of Ash Chapter 1 Chapter 2 Chapter 3 Chapter 4 Chapter 5 Chapter 6 Chapter 7 Chapter 8 Chapter 9 Chapter 10 Chapter 11 Chapter 12 Chapter 13 Chapter 14 Chapter 15 Chapter 16 Chapter 17 Chapter 18 Chapter 19 Chapter 20 Chapter 21 Chapter 22 Chapter 23 Chapter 24 Chapter 25 Chapter 26 Chapter 27 Chapter 28 Chapter 29 Chapter 30 .
TO KILL A MOCKINGBIRD. Contents Dedication Epigraph Part One Chapter 1 Chapter 2 Chapter 3 Chapter 4 Chapter 5 Chapter 6 Chapter 7 Chapter 8 Chapter 9 Chapter 10 Chapter 11 Part Two Chapter 12 Chapter 13 Chapter 14 Chapter 15 Chapter 16 Chapter 17 Chapter 18. Chapter 19 Chapter 20 Chapter 21 Chapter 22 Chapter 23 Chapter 24 Chapter 25 Chapter 26
Non-Ionizing Radiation Non-ionizing radiation includes both low frequency radiation and moderately high frequency radiation, including radio waves, microwaves and infrared radiation, visible light, and lower frequency ultraviolet radiation. Non-ionizing radiation has enough energy to move around the atoms in a molecule or cause them to vibrate .
Medical X-rays or radiation therapy for cancer. Ultraviolet radiation from the sun. These are just a few examples of radiation, its sources, and uses. Radiation is part of our lives. Natural radiation is all around us and manmade radiation ben-efits our daily lives in many ways. Yet radiation is complex and often not well understood.
DEDICATION PART ONE Chapter 1 Chapter 2 Chapter 3 Chapter 4 Chapter 5 Chapter 6 Chapter 7 Chapter 8 Chapter 9 Chapter 10 Chapter 11 PART TWO Chapter 12 Chapter 13 Chapter 14 Chapter 15 Chapter 16 Chapter 17 Chapter 18 Chapter 19 Chapter 20 Chapter 21 Chapter 22 Chapter 23 .
Radiation Protection Series . The Radiation Protection Series is published by the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) to promote practices which . National Conference on Radiation Protection in Medicine was held on 3 October 2007, during the public consultation period, to provide the stakeholders a .
The Assistant Radiation Safety Officer (ARSO) assists the RSO in the management of the Radiation Protection Program. Radiation Safety Committee: The Radiation Safety Committee (RSC) is a body consisting of the RSO, ARSO, Executive Manager and persons trained and experienced in the safe use of radioactive materials and radiation producing devices.
Ionizing radiation: Ionizing radiation is the highenergy radiation that - causes most of the concerns about radiation exposure during military service. Ionizing radiation contains enough energy to remove an electron (ionize) from an atom or molecule and to damage DNA in cells.
