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IAEA Training Material on Radiation Protection in Radiotherapy. Radiation Protection in Radiotherapy. Part 4 Principles of Radiation Protection Lecture 2: The BSS Framework. The IAEA. International Atomic Energy Agency
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IAEA Training Material on Radiation Protection in Radiotherapy Radiation Protection inRadiotherapy Part 4 Principles of Radiation Protection Lecture 2: The BSS Framework
The IAEA • International Atomic Energy Agency • Objective to seek to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world. • Authorised to establish standards of safety for the protection of health … and to provide for the application of these standards Part 4, lecture 2: The BSS framework
IAEA assembly Part 4, lecture 2: The BSS framework
The IAEA Basic Safety Standards • International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources, IAEA Safety Series No 115, Vienna 1996 (IAEA, FAO, ILO, OECD/NEA, PAHO and WHO) Part 4, lecture 2: The BSS framework
The Basic Safety Standards Sponsored by many international institutions A practical guide; the BSS lays down basic principles and provides requirements for protection and safety To be filled by more specific information through guidelines and codes of practice Part 4, lecture 2: The BSS framework
Objectives of the lecture • To become familiar with the terminology and requirements of the BSS • To be able to apply the requirements of the BSS to the radiotherapy environment • To appreciate the importance of an internationally harmonized set of safety standards, such as the BSS, for day to day radiotherapy practice Part 4, lecture 2: The BSS framework
Contents 1. Background and structure of the BSS 2. Some terminology 3. BSS requirements 4. The BSS Appendices and Schedules Part 4, lecture 2: The BSS framework
1. Historical Background • First Basic Safety Standards 1962 • Revised Basic Safety Standards 1967 • Revised and Joint with FAO, ILO, OECD/NEA, WHO 1982 • ICRP published revised recommendations 1991 • Consultants, Senior experts meetings, ad hoc 1991-1993 working groups, technical committees • 6th draft circulated to all member states Mar 1994 • 7th Draft approved by IAEA Board of Governors Sept 1994 • Publication of Interim Version S.S.115I 1994 • Formal approval by co-sponsoring organizations 1994-1996 • Publication of S.S.115 1996 Part 4, lecture 2: The BSS framework
Jointly sponsored by: THE FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS THE INTERNATIONAL ATOMIC ENERGY AGENCY THE INTERNATIONAL LABOUR ORGANIZATION THE NUCLEAR ENERGY AGENCY OF THE OECD THE PAN AMERICAN HEALTH ORGANIZATION and THE WORLD HEALTH ORGANIZATION Part 4, lecture 2: The BSS framework
Hierarchy of IAEA documents Safety Fundamentals Safety Standards Approved by IAEA Board of Governors Part 4, lecture 2: The BSS framework
Hierarchy of IAEA documents Part 4, lecture 2: The BSS framework
Objectives of the BSS • The objective is to establish basic requirements for protection against the risks associated with exposure to ionizing radiation and for the safety of radiation sources that may deliver such exposure. • The Standards have been developed from widely accepted radiation protection and safety principles, such as those published in the Annals of the ICRP and the IAEA Safety Series. Part 4, lecture 2: The BSS framework
LAYOUT of the BSS PREAMBLE: Principles and Fundamental Objectives PRINCIPLE REQUIREMENTS: General-responsibilities and organizational Practices Interventions APPENDICES: DETAILED REQUIREMENTS Occupational exposure Medical exposure Public exposure Potential exposure: safety of sources Emergency exposure situations Chronic exposure situations ANNEXES: Numerical Part 4, lecture 2: The BSS framework
The Scope of the BSS • The Standards comprise basic requirements to be fulfilled in all activities involving radiation exposure. • The Standards lay down basic principles and indicate the different aspects that should be covered by an effective radiation protection programme. • They are not intended to be applied as they stand in all countries and regions , but should be interpreted to take account of local situations, technical resources, the scale of installations and other factors. Part 4, lecture 2: The BSS framework
Applicability of the BSS The Standards apply to practices and interventions: (a) carried out in a State that adopts the BSS (b) undertaken by States with assistance of FAO, IAEA, ILO, PAHO or WHO (c) carried out by IAEA or with materials, services, equipment and non-published information made available by the IAEA (d) where parties to bi/multi-lateral arrangements request application Part 4, lecture 2: The BSS framework
EXCLUSION • Any exposure whose magnitude or likelihood is essentially unnamable to control, e.g. • 40K in the body, • cosmic radiation at earth’s surface • and unmodified concentrations of radionuclides in most raw materials. Part 4, lecture 2: The BSS framework
EXEMPTION • Practice or source may be exempted if • effective dose < 10mSv in a year • collective effective dose committed by one year of practice < 1manSv • or • exemption is the optimum option (using model scenarios derived nuclide-specific levels) Part 4, lecture 2: The BSS framework
GENERAL OBLIGATIONS • Unless excluded or exempted (numerical criteria nuclide specific values) the standards apply - including requirements for • notification • registration • licensing • Each application for authorization requires a safety assessment. • Each release of items from authorized premises requires clearance. authorization Part 4, lecture 2: The BSS framework
2. BSS: Some Terminology • Definition of many terms is in • IAEA publication: Safety Fundamentals, Safety Series 120, 1996 and • BSS glossary Part 4, lecture 2: The BSS framework
Authorization: registration or licensing BSS 2.11.: “The Legal person responsible for any sealed source, unsealed source or radiation generator shall, unless the source is exempted, apply to the Regulatory Authority for an authorization which shall take the form of either a registration or a licence.” This applies to a radiotherapy department Part 4, lecture 2: The BSS framework
Authorization: registration or licensing BSS 2.14.: “The legal person responsible for a source to be used for medical exposure shall include in the application for authorization: • (a) the qualifications in radiation protection of the medical practitioners who are to be so designated by name in the registration or licence; or • (b) a statement that only medical practitioners with the qualifications in radiation protection specified in the relevant regulations or to be specified in the registration or licence will be permitted to prescribe medical exposure by means of the authorized source.” This applies to radiotherapy Part 4, lecture 2: The BSS framework
Authorized legal persons: registrants and licensees • BSS 2.15.: “Registrants and licensees shall bear the responsibility for setting up and implementing the technical and organizational measures that are needed for ensuring protection and safety for the sources for which they are authorized. • They may appoint other people to carry out actions and tasks related to these responsibilities, but they shall retain the responsibility for the actions and tasks themselves.” Part 4, lecture 2: The BSS framework
Quick question Who is ultimately responsible for radiation protection in your facility?
Practice Any human activity that introduces or extends sources of exposure or exposure pathways. Radiotherapy is a ‘practice’ Part 4, lecture 2: The BSS framework
Practices can alter exposure Dose Additional dose attributable to the practice, DE Post-practice extant dose Pre-practiceextant dose Time Introduction, operation and decommissioning of a beneficial practice Part 4, lecture 2: The BSS framework
Any action intended to reduce or avert exposure or the likelihood of exposure to sources which are not part of a controlled practice or which are out of control. Intervention Without intervention radiotherapy would result in large exposures not only for the patient but also for staff, visitors and general public Part 4, lecture 2: The BSS framework
Interventions Averted dose by the intervention Dose Post-intervention dose Pre-intervention dose Time Undertaking intervention Part 4, lecture 2: The BSS framework
Enforcement of the Standards is the responsibility of national government. This requires a national infrastructure: Legislation & Regulations Regulatory Authority Trained personnel National Infrastructure Part 4, lecture 2: The BSS framework
Regulatory Authority ESTABLISHED BY GOVERNMENT Given: - Sufficient powers - Resources - Independence (effective) To: - Receive Notifications - Carry out assessments - Issue Authorizations/Licenses - Inspect - Enforce Part 4, lecture 2: The BSS framework
3. The Principal Requirements of the BSS • Specifies who are the responsible organizations and individuals, including the Regulatory Authority. • Defines the administrative requirements, including licensing and registration. • Uses the dose limitation system introduced in ICRP report 60. • The detailed requirements are given in a number of Appendices and Schedules. Part 4, lecture 2: The BSS framework
A) Allocation of responsibility B) Administrative requirements C) Radiation protection requirements D) Management requirements E) Technical requirements F) Verification of Safety Principal Requirements of the BSS Part 4, lecture 2: The BSS framework
A) Allocation of responsibilities • In radiotherapy: • Emergency Situations • Occupational Exposure • Medical Exposure • Public Exposure • Safety of Sources Part 4, lecture 2: The BSS framework
A) Allocation of responsibilities • In radiotherapy: • Emergency Situations - part 13 • Occupational Exposure - part 8 • Medical Exposure - parts 9-12 • Public Exposure - part 17 • Safety of Sources - part 15 Part 4, lecture 2: The BSS framework
Responsibilities for Occupational Exposure BSS Appendix I.1. Registrants and licensees and employers of workers who are engaged in activities involving normal exposures or potential exposure shall be responsible for: • (a) the protection of workers from occupational exposure; and • (b) compliance with any other relevant requirements of the Standards. More details in part 8 of the course Part 4, lecture 2: The BSS framework
Responsibilities for Medical Exposure BSS Appendix II.1. Registrants and licensees shall ensure that: (a) no patient be administered a diagnostic or therapeutic medical exposure unless the exposure is prescribed by a medical practitioner; (d) for therapeutic uses of radiation, the calibration, dosimetry and quality assurance requirements of the Standards be conducted by or under the supervision of a qualified expert in radiotherapy physics; More details in parts 9 to 13 of the course Part 4, lecture 2: The BSS framework
Responsibilities for Public Exposure (BSS III.2 ) III.1. Registrants and licensees shall apply the requirements of the Standards as specified by the Regulatory Authority to any public exposure delivered by a practice or source for which they are responsible, unless the exposure is excluded from the Standards or the practice or source delivering the exposure is exempted from the requirements of the Standards. The BSS is applicable to radiotherapy - more details in part 17 of the course Part 4, lecture 2: The BSS framework
B) Administrative requirements • Notification • Authorization (Registration/Licensing) • as discussed before • included are requirements for ‘authorized legal persons’: BSS 2.15. “Registrants and licensees shall bear the responsibility for setting up and implementing the technical and organizational measures that are needed for ensuring protection and safety for the sources for which they are authorized. They may appoint other people to carry out actions and tasks related to these responsibilities, but they shall retain the responsibility for the actions and tasks themselves. Registrants and licensees shall specifically identify the individuals responsible for ensuring compliance with the Standards.” Part 4, lecture 2: The BSS framework
Notification • BSS 2.10. “Any legal person intending to carry out any of the actions specified under the General Obligations for practices of the Standards (see paras 2.7 and 2.8) shall submit a notification to the Regulatory Authority of such an intention [6]. Notification for consumer products is required only with respect to manufacturing, assembling, importing and distributing.” Part 4, lecture 2: The BSS framework
C) RADIATION PROTECTION REQUIREMENTS • Justification of Practices • positive net benefit • Dose Limitation • dose limits • Optimization of Protection and Safety • Constraints • of various types • guidance levels for medical exposure. Part 4, lecture 2: The BSS framework
Radiation protection requirements JUSTIFICATION OF PRACTICES “Practices should not be authorized unless the benefits are greater than the detriments, taking account of social, economic and other factors” Part 4, lecture 2: The BSS framework
Radiation protection requirements DOSE LIMITATION “The normalexposure of individuals from authorized practices shall not exceed the dose limits specified in Schedule II of BSS” Part 4, lecture 2: The BSS framework
Dose limits - BSS schedule II OCCUPATIONAL EXPOSURE: II-5. The occupational exposure of any worker shall be so controlled that the following limits be not exceeded: (a) an effective dose of 20 mSv per year averaged over five consecutive years; (b) an effective dose of 50 mSv in any single year; (c) an equivalent dose to the lens of the eye of 150 mSv in a year; and (d) an equivalent dose to the extremities (hands and feet) or the skin [39] of 500 mSv in a year. More details in part 8 of the course Part 4, lecture 2: The BSS framework
Dose limits - BSS schedule II PUBLIC EXPOSURE II-8. The estimated average doses to the relevant critical groups of members of the public that are attributable to practices shall not exceed the following limits: (a) an effective dose of 1 mSv in a year; (b) in special circumstances, an effective dose of up to 5 mSv in a single year provided that the average 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; and (d) an equivalent dose to the skin of 50 mSv in a year. More details in part 17 of the course Part 4, lecture 2: The BSS framework
Radiation protection requirements OPTIMIZATION OF PROTECTION AND SAFETY “Doses to individuals, the number of persons and the likelihood of incurring exposures shall be kept as low as reasonably achievable, economic and social factors taken into account” Part 4, lecture 2: The BSS framework
Radiation protection requirements DOSE CONSTRAINTS “Optimization of protection and safety measures associated with a particular source within a practice shall be subject to dose constraints” Dose constraints are used prospectively e.g. at the design stage of the facility Part 4, lecture 2: The BSS framework
D) MANAGEMENT REQUIREMENTS • Safety Culture • Quality Assurance • Human Factors • Qualified Experts Part 4, lecture 2: The BSS framework
Management requirements SAFETY CULTURE Purpose: To encourage a questioning and learning attitude to protection and safety, whilst discouraging complacency. Policies and procedures should: • identify protection and safety as the highest priority • Identify problems promptly • Identify responsibilities of individuals • define clear lines of authority (to the top) • effect lines of communication Part 4, lecture 2: The BSS framework
Management requirements QUALITY ASSURANCE Establish QA programme to ensure: • that safety and protection requirements are satisfied • the overall effectiveness of protection and safety is periodically reviewed • this requires significant commitment from management (logistical and financial resources) Part 4, lecture 2: The BSS framework
Management requirements HUMAN FACTORS The contribution of human error to accidents should be minimized by: • training of personnel • use of defined procedures • use of ergonomic design to minimize operating errors • use of safety systems Part 4, lecture 2: The BSS framework
Management requirements QUALIFIED EXPERTS Identify need and make available, for example: • Advice on radiation protection and safety • Servicing and maintenance • Calibration, clinical dosimetry... Part 4, lecture 2: The BSS framework