IAEA-50-SG-O12-1994.pdf

I A E A 50-SG-OL2 94 9006333 0007342 B T B SAFETY SERIES NO. 50-SG-012 nu Periodic Safety Review of Operational Nuclear Power Plants A Safety Guide A PUBLICATION WITHIN THE NUSS PROGRAMME INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1994 -,-,- IAEA 50-SG-012 94 9006333 0007343 734 CATEGORIES IN THE IAEA SAFETY SERIES A new hierarchical categorization scheme has been introduced, according to which the publications in the IAEA Safety Series are grouped as follows: Safety Fundamentals (silver cover) Basic objectives, concepts and principles to ensure safety Safety Standards (red cover) Basic requirements which must be satisfied to ensure safety for particular activities or application areas. Safety Guides (green cover) Recommendations, on the basis of international experience, relating to the ful- filment of basic requirements. Safety Practices (blue cover) Practical examples and detailed methods which can be used for the application of Safety Standards or Safety Guides. Safety Fundamentals and Safety Standards are issued with the approval of the IAEA Board of Governors; Safety Guides and Safety Practices are issued under the authority of the Director General of the IAEA. An additional category, Safety Reports (purple cover), comprises independent reports of expert groups on safety matters, including the development of new princi- ples, advanced concepts and major issues and events. These reports are issued under the authority of the Director General of the IAEA. There are other publications of the IAEA which also contain information important to safety, in particular in the Proceedings Series (papers presented at symposia and conferences), the Technical Reports Series (emphasis on technological aspects) and the IAEA-TECDOC Series (information usually in a preliminary form). -,-,- PERIODIC SAFETY REVIEW OF OPERATIONAL NUCLEAR POWER PLANTS A Safety Guide -,-,- IAEA 50-SG-O32 74 7006333 0007345 507 = The following States are Members of the International Atomic Energy Agency: AFGHANISTAN ALBANIA ALGERIA ARGENTINA ARMENIA AUSTRALIA AUSTRIA BANGLADESH BELARUS BELGIUM BOLIVIA BRAZIL BULGARIA CAMBODIA CAMEROON CANADA CHILE CHINA COLOMBIA COSTA RICA COTE DIVOIRE CROATIA CUBA CYPRUS CZECH REPUBLIC DENMARK DOMINICAN REPUBLIC ECUADOR EGYPT EL SALVADOR ESTONIA ETHIOPIA FINLAND FRANCE GABON GERMANY GHANA GREECE GUATEMALA HAITI HOLY SEE HUNGARY ICELAND INDIA INDONESIA IRAN, IRAQ IRELAND ISRAEL ITALY JAMAICA JAPAN JORDAN KAZAKHSTAN KENYA KOREA, REPUBLIC OF KUWAIT LEBANON LIBERIA LIBYAN ARAB JAMAHIRIYA LIECHTENSTEM LITHUANIA LUXEMBOURG MADAGASCAR MALAYSIA MALI MARSHALL ISLANDS MAURFTIUS MEXICO MONACO MONGOLIA MOROCCO MYANMAR NAMIBIA NETHERLANDS NEW ZEALAND NICARAGUA NIGER NIGERIA NORWAY PAKISTAN PANAMA PARAGUAY ISLAMIC REPUBLIC OF PERU PHILIPPINES POLAND PORTUGAL QATAR ROMANIA RUSSIAN FEDERATION SAUDI ARABIA SENEGAL SIERRA LEONE SINGAPORE SLOVAKIA SLOVENIA SOUTH AFRICA SPAIN SRI LANKA SUDAN SWEDEN SWITZERLAND SYRIAN ARAB REPUBLIC THAILAND THE FORMER YUGOSLAV REPUBLIC OF MACEDONIA TUNISIA TURKEY UGANDA UKRAINE UNITED ARAB EMIRATES UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND UNITED REPUBLIC OF TANZANIA UNITED STATES OF AMERICA URUGUAY UZBEKISTAN VENEZUELA VIET NAM YUGOSLAVIA ZAIRE ZAMBIA ZIMBABWE The Agencys Statute was approved on 23 October 1956 by the Conference on the Statute of the IAEA held at United Nations Headquarters, New York; it entered into force on 29 July 1957. The Head- quarters of the Agency are situated in Vienna. Its principal objective is “to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world”. 0 IAEA. 1994 Permission to reproduce or translate the information contained in this publication may be obtained by writing to the International Atomic Energy Agency, Wagramerstrasse 5, P.O. Box 100, A-1400 Vienna, Austria. Printed by the IAEA in Austria November 1994 -,-,- SAFETY SERIES No. 50-SG-012 PERIODIC SAFETY REVIEW OF OPERATIONAL NUCLEAR POWER PLANTS A Safety Guide INTERNATIONAL ATOMIC ENERGY AGENCY VIENNA, 1994 -,-,- I A E A 50-SG-012 94 = 700b331 0007347 38T H THIS SAFETY SERIES PUBLICATION IS ALSO ISSUED IN FRENCH, RUSSIAN AND SPANISH WC Library Cataloguing in Publication Data Periodic safety review of operational nuclear power plants : a safety guide. - p. ; 24 cm. - (Safety series, ISSN 0074-1892 ; JO-SG-012. Safety Vienna : International Atomic Energy Agency, 1994. guides) On cover: A publication within the NUSS Programme. STIfPUBf963 Includes bibliographical references. 1. Nuclear power plants-Safety measures. ISBN 92-0-103894-1 I. Nuclear Safety Standards Programme. II. International Atomic Energy Agency. III. Series. VICL 94-00100 -,-,- I A E A 50-SG-012 74 = 7006333 000714ô 2Lh = FOREWORD by the Director General Nuclear power is well established and can be expected to become an even more significant part of the energy programmes of many countries, provided that its safe use can be ensured and be perceived to be so ensured. Although accidents have occurred, the nuclear power industry has generally maintained a good safety record. However, improvements are always possible and necessary. Safety is not a static concept. The International Atomic Energy Agency, recognizing the importance of the safety of the industry and desiring to promote an improving safety record, set up a programme in 1974 to give guidance to its Member States on the many aspects of the safety of nuclear power reactors. Under this Nuclear Safety Standards (NUSS) programme, some 60 Codes and Safety Guides dealing with radiological safety were published in the IAEA Safety Series between 1978 and 1986. The NUSS programme was developed for land based stationary plants with thermal neutron reactors designed for the production of power but the provisions may be appropriate to a wider range of nuclear applications. In order to take account of lessons learned since the first publication of the NUSS programme was issued, it was decided in 1986 to revise and reissue the Codes and Safety Guides. During the original development of these publications, as well as during the revision process, care was taken to ensure that all Member States, in particular those with active nuclear power programmes, could provide their input. Several independent reviews took place including a final one by the Nuclear Safety Standards Advisory Group (NUSSAG). The revised Codes were approved by the Board of Governors in June 1988. In the revision process new developments in technology and methods of analysis have been incorporated on the basis of interna- tional consensus. It is hoped that the revised Codes will be used, and that they will be accepted and respected by Member States as a basis for regulation of the safety of power reactors within the national legal and regulatory framework. Any Member State wishing to enter into an agreement with the IAEA for its assistance in connection with the siting, design, construction, commissioning, operation or decommissioning of a nuclear power plant will be required to follow those parts of the Codes and Safety Guides that pertain to the activities to be covered by the agreement. However, it is recognized that the final decisions and legal responsibilities in any licensing procedures rest with the Member States. The Codes and Safety Guides are presented in such a form as to enable a Member State, should it so desire, to make their contents directly applicable to activities under its jurisdiction. Therefore, consistent with the accepted practice for codes and guides, and in accordance with a proposal of the Senior Advisory Group, -,-,- IAEA 50-SG-032 94 9006333 0007349 152 shall and should are used to distinguish for the user between strict requirements and desirable options respectively. The five Codes deal with the following topics: - Governmental organization - Siting - Design - Operation - Quality assurance. These five Codes establish the objectives and basic requirements that must be met to ensure adequate safety in the operation of nuclear power plants. The Safety Guides are issued to describe to Member States acceptable methods of implementing particular parts of the relevant Codes. Methods and solutions other than those set out in these Guides may be acceptable, provided that they give at least equivalent assurance that nuclear power plants can be operated without undue risk to the health and safety of the general public and site personnel. Although these Codes and Safety Guides establish an essential basis for safety, they may require the incorporation of more detailed requirements in accordance with national practice. Moreover, there will be special aspects that need to be assessed by experts on a case by case basis. These publications are intended for use, as appropriate, by regulatory bodies and others concerned in Member States. In order to comprehend the contents of any of them fully, it is essential that the other relevant Codes and Safety Guides be taken into account. Other safety publications of the IAEA should be consulted as necessary. The physical security of fissile and radioactive materials and of nuclear power plants as a whole is mentioned where appropriate but is not treated in detail. Non-radiological aspects of industrial safety and environmental protection are also not explicitly considered. The requirements and recommendations set forth in the NUSS publications may not be fully satisfied by older plants. The decision of whether to apply them to such plants must be made on a case by case basis according to national circumstances. -,-,- CONTENTS DEFINITIONS 1 . INTRODUCTION . Background (101 . 103) Objective (104) . Scope (105-106) . Structure (107) . 2 . RATIONALE FOR AND OBJECTIVE OF PERIODIC SAFETY REVIEW . Rationale for a PSR (201-206) . Objective of a PSR (207) 3 . REVIEW STRATEGY (301-308) 4 . SAFETY FACTORS IN A PERIODIC SAFETY REVIEW . Introduction (40 1-409) . Safety analysis (412-415) Actual physical condition of the nuclear power plant (410-411) Equipment qualification (4 16-4 19) . Management of ageing (420-423) Safety performance (424-426) Use of experience from other plants and research findings (427-428) Procedures (429-430) . Organization and administration (43 1-432) Human factors (433-434) Emergency planning (435-436) . Environmental impact (437-438) . 5 . ROLES AND RESPONSIBILITIES (501-504) . 6 . REVIEW PROCEDURE . Introduction (601 -602) . Step 1: Assessment of current nuclear power plant safety (603) Step 2: Interim safety review (604-606) Step 3: In-depth safety review (607-611) 1 8 9 9 10 11 12 13 14 15 16 16 17 17 18 19 19 19 24 24 25 -,-,- IAEA 50-SG-O32 94 9006333 0007151 800 7 . BASIS FOR ACCEPTABILITY OF CONTINUED PLANT OPERATION (701-703) 26 8 . POST-REVIEW ACTIVITIES (801-803) 27 APPENDIX: ELEMENTS OF REVIEW 29 REFERENCES 35 CONTRIBUTORS TO DRAFTING AND REVIEW 37 LIST OF NUSS PROGRAMME TITLES . 39 SELECTION OF IAEA PUBLICATIONS RELATING TO THE SAFETY OF NUCLEAR POWER PLANTS . 43 -,-,- I A E A 50-SG-O12 94 9006333 0007352 747 DEFINITIONS ïñe definitions below are intended for use in the NUSS programme and may not necessarily conform to definitions adopted elsewhere for international use. ïñe relationships between the following fundamental definitions used in many NUSS publications are illustrated by the accompanying diagram. Operationai States States defined under normal operation or Anticipated Operational Occurrences. Normal Operation Operation of a nuclear power plant within specified operational limits and conditions including shutdown, power operation, shutting down, starting, main- tenance, testing and refuelling. Anticipated Operational Occurrences' All operational processes deviating from normal operation which are expected to occur once or several times during the operating life of the plant and which, in view of appropriate design provisions, do not cause any significant damage to items important to Safety nor lead to Accident Conditions. Accident (or Accident State) A state defined under Accident Conditions or Severe Accidents. Accident Conditions Deviations2 from Operational States in which the releases of radioactive materials are kept to acceptable limits by appropriate design features. These devia- tions do not include severe accidents. ' Examples of Anticipated Operational Occurrences are loss of n o d electric power and faults such as a turbine trip, malfunction of individual items of a normally running plant, failure to function of individual items of control equipment, loss of power to main coolant Pump. A deviation may be a major fuel failure, a loss of coolant accident (LOCA), etc. 1 -,-,- IAEA 50-SG-O12 94 H 700b332 0007253 683 H conditions I Design B a s i s Accidents accidents Accident Conditions against which the nuclear power plant is designed accord- ing to established design criteria. Severe Accidents Nuclear power plant states beyond Accident Conditions including those causing significant core degradation. Accident Management Accident management is the taking of a set of actions - during the evolution of an event sequence, before the design basis of the plant - during Severe Accidents without core degradation, or - after core degradation has occurred is exceeded, or to return the plant to a controlled safe state and to mitigate any consequences of the accident. Plant states Accidents I Operational states I I I I I l I I 1 I I Accidcnr management I 2 -,-,- IAEA 50-SG-012 74 7006331 0007154 5LT The relationships between the following dejbition, which refer especially to the area of design, are given in the accompanying diagram. safety - See Nuclear Safety Nuclear Safety (or simply Safety) The achievement of proper operating conditions, prevention of accidents or mitigation of accident consequences, resulting in protection of site personnel, the public and the environment from undue radiation hazards. Safety systems3 Systems important to Safety, provided to assure the safe shutdown of the reactor or the residual heat removal from the core, or to limit the consequences of Anticipated Operational Occurrences or Accident Conditions. Protection System A system which encompasses all electrical and mechanical devices and circuitry, from sensors to actuation device input terminals, involved in generating those signals associated with the protective function. Safety Actuation System The collection of equipment required to accomplish the necessary sa