N290.4-11

Requirements for reactor control systems of nuclear power plants

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CSA Standards Update Service

N290.4-11

October 2011

Title: Requirements for reactor control systems of nuclear power plants

Pagination: 20 pages (viii preliminary and 12 text), each dated October 2011

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CSA Standard

N290.4-11

Requirements for reactor control systems of nuclear power plants

Published in October 2011 by Canadian Standards Association A not-for-profit private sector organization

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ISBN 978-1-55491-653-5

© Canadian Standards Association — 2011

All rights reserved. No part of this publication may be reproduced in any form whatsoever without the prior permission of the publisher.

© Canadian Standards Association Requirements for reactor control systems of nuclear power plants

Contents

Technical Committee on Reactor Control Systems, Safety Systems, and Instrumentation of Nuclear Power Plants iv

Subcommittee on Reactor Control Systems of Nuclear Power Plants vi

Preface vii

1. Scope 1

   
   

2. Reference publications 2

   
   

3. Definitions 3

   
   

4. Functional requirements 4

   1. Normal operation 4

   2. Anticipated operational occurrences (AOOs) 5

   3. Design basis accidents (DBAs) 5

      
      

5. Requirements 5

   1. Operating experience 5

   2. Separation and independence between the reactor control system and shutdown systems 5

   3. Relationship of the reactor control system to other process systems 5

   4. Reliability 6

   5. Fail-safe design 6

   6. Control devices 6

   7. Reactor start-up 7

   8. Response following a reactor trip 7

   9. Reactor subcritical 7

   10. Reactor power measurement 8

   11. Human-system interface 8

   12. Testing 9

   13. Maintenance capability 9

   14. Standards for pressure-retaining piping components 9

   15. Standards for instrumentation and interconnections 10

   16. Equipment qualification 10

       1. General 10

       2. Environmental qualification 10

       3. Seismic qualification 10

       4. Ageing management 10

   17. Software design 11

   18. Cyber security 11

   19. Control stability 11

   20. Chemistry 11

       
       

6. Quality management 11

Annexes

A (informative) — Guidance on control logic implementation 12

October 2011 iii

N290.4-11 © Canadian Standards Association

Technical Committee on Reactor Control Systems, Safety Systems, and Instrumentation of Nuclear Power Plants

J. Grava CANTECH Associates Ltd., Owen Sound, Ontario

Chair

R. Black RCM Technologies Canada Corp., Pickering, Ontario

Vice-Chair

B. Coulas Bruce Power Inc., Tiverton, Ontario

Vice-Chair

1. Babcock Ontario Power Generation Inc., Pickering, Ontario

   Associate

   Q.-B.J. Chou Canadian Power Utility Services Ltd., Toronto, Ontario

2. Daniel Ontario Power Generation Inc., Pickering, Ontario

G. Davies RCM Technologies Canada Corp., Pickering, Ontario

Associate

M. Debly NB Power Nuclear Corporation, Lepreau, New Brunswick

A. Faya Federal Authority for Nuclear Regulation, Abu Dhabi, UAE

Associate

M. Gerard Ontario Power Generation Inc., Pickering, Ontario

Associate

M. Kotb Régie du bâtiment du Québec, Montréal, Québec

U. Kukreti RCM Technologies Canada Corp., Pickering, Ontario

Associate

W. Lam Ministry of Energy, Toronto, Ontario

P. Lee Atomic Energy of Canada Limited, Mississauga, Ontario

iv October 2011

© Canadian Standards Association Requirements for reactor control systems of nuclear power plants

H. Leung HCL Inc., Toronto, Ontario

Associate

R.P. Lindsay RCM Technologies Canada Corp., Pickering, Ontario

Associate

R. Lojk Canadian Nuclear Safety Commission, Ottawa, Ontario

L. Luckhardt Dresser Flow Solutions, Burlington, Ontario

S. MacDonald Manchester Consulting, Saint John, New Brunswick

J. Pilgrim GE-Hitachi, Peterborough, Ontario

G. Ridgway GE-Hitachi, Peterborough, Ontario

Associate

B. Rolfe Rolfe and Associates, Mississauga, Ontario

G. Waterhouse Nuclear Logistics Inc. (Canada),

Bowmanville, Ontario

B. Willemsen NB Power Nuclear Corporation, Lepreau, New Brunswick

Associate

M. Cianchetti Canadian Standards Association, Mississauga, Ontario

Project Manager

S. Oh Canadian Standards Association, Mississauga, Ontario

Project Manager

October 2011 v

N290.4-11 © Canadian Standards Association

Subcommittee on Reactor Control Systems of Nuclear Power Plants

B. Babcock Ontario Power Generation Inc., Pickering, Ontario

Chair

M. Borairi Atomic Energy of Canada Limited, Mississauga, Ontario

G. Chun Canadian Nuclear Safety Commission, Ottawa, Ontario

A. Firla Canadian Power Utility Services Ltd., Toronto, Ontario

P. Gribbons Bruce Power Inc., Tiverton, Ontario

R. Nicholls Hydro-Québec, Gentilly, Québec

P. Paquette Bruce Power Inc., Tiverton, Ontario

R. Prime NB Power Nuclear Corporation, Lepreau, New Brunswick

M. Cianchetti Canadian Standards Association, Mississauga, Ontario

Project Manager

S. Oh Canadian Standards Association, Mississauga, Ontario

Project Manager

vi October 2011

© Canadian Standards Association Requirements for reactor control systems of nuclear power plants

Preface

This is the second edition of CSA N290.4, Requirements for reactor control systems of nuclear power plants. It supersedes the previous edition published in 1982. The title has been changed to reflect a change of scope. The new edition not only addresses CANDU reactors but also addresses other types of water-cooled power reactors.

The development of the original Standard was initiated by the Canadian Nuclear Association to help prospective owners of nuclear power plants, as well as designers, manufacturers, fabricators, and installers of nuclear power plant components, by compiling the various requirements of regulatory authorities.

Major changes to this edition include

1. broadening of requirements to incorporate other water-cooled reactor technologies;

2. improved integration with associated standards; and

3. incorporation of current terminology and operating experience.

   The specific objective of this Standard is to establish the minimum requirements for the design, manufacture and fabrication, qualification, and installation of reactor control systems in nuclear power plants, in order to ensure that they will operate as intended. The purpose of this Standard is not to limit improved system design but to provide a minimum base against which innovations and new techniques can be compared.

   The CSA N-Series of Standards provides an interlinked set of requirements for the management of nuclear facilities and activities. CSA N286 provides overall direction to management to develop and implement sound management practices and controls, while the other CSA nuclear Standards provide technical requirements and guidance that support the management system. This Standard works in harmony with CSA N286 and does not duplicate the generic requirements of CSA N286; however, it may provide more specific direction for those requirements.

   Users of this Standard are reminded that the design, manufacture, construction, commissioning, operation, and decommissioning of nuclear facilities in Canada are subject to the provisions of the Nuclear Safety and Control Act and its supporting Regulations.

   This Standard has been prepared by the Subcommittee on Reactor Control Systems of Nuclear Power Plants, under the jurisdiction of the Technical Committee on Reactor Control Systems, Safety Systems, and Instrumentation of Nuclear Power Plants, and the Standards Steering Committee on Nuclear Standards.

   
   

   October 2011

   
   

   Notes:

   1. Use of the singular does not exclude the plural (and vice versa) when the sense allows.

   2. Although the intended primary application of this Standard is stated in its Scope, it is important to note that it remains the responsibility of the users of the Standard to judge its suitability for their particular purpose.

   3. This publication was developed by consensus, which is defined by CSA Policy governing standardization — Code of good practice for standardization as “substantial agreement. Consensus implies much more than a simple majority, but not necessarily unanimity”. It is consistent with this definition that a member may be included in the Technical Committee list and yet not be in full agreement with all clauses of this publication.

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         October 2011 vii

         N290.4-11 © Canadian Standards Association

         
         

         
         

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viii October 2011

© Canadian Standards Association Requirements for reactor control systems of nuclear power plants

N290.4-11

Requirements for reactor control systems of nuclear power plants

1 Scope

1.1

This Standard specifies provisions for safe and effective control of reactor power.

1.2

This Standard pertains to all components of the system, including mechanical, process, software, electrical, and instrumentation and control design used for the control of the neutron flux and the thermal output of the reactor.

1.3

In this Standard, “control” refers to both manual and automatic action.

1.4

In this Standard, “control” refers to reactor power control, not overall unit control.

1.5

This Standard provides provisions for a design that facilitates reactivity management.

Note: For the purposes of this Standard, “reactivity management” refers to

1. the safe, controlled, and conservative performance of plant operation and maintenance activities that affect reactivity;

2. the active and vigilant monitoring of reactivity changes;

3. the quick and reliable detection of deviations from expected results; and

4. limiting rate changes and maximum power changes in response to failures.

1.6

In CSA standards, “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; “should” is used to express a recommendation or that which is advised but not required; and “may” is used to express an option or that which is permissible within the limits of the standard.

Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.

Notes to tables and figures are considered part of the table or figure and may be written as requirements.

Annexes are designated normative (mandatory) or informative (nonmandatory) to define their application.

October 2011 1