CSA N290.4:19

Requirements for reactor control systems of nuclear power plants

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  CSA N290.4:19

  June 2019

  
  

  Title: Requirements for reactor control systems of nuclear power plants

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CSA N290.4:19

Requirements for reactor control systems of nuclear power plants

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Contents

Technical Committee on Reactor Control Systems, Safety Systems, and Instrumentation for Nuclear Power Plants 3

Subcommittee on Requirements for Reactor Control Systems of Nuclear Power Plants 6

Preface 7

1. Scope 9

   
   

2. Reference publications 9

   
   

3. Definitions and abbreviations 12

   1. Definitions 12

   2. Abbreviations 14

      
      

4. Requirements 14

   1. Operating experience input 14

   2. Functional requirements 14

      1. Normal operation 14

      2. Anticipated operational occurrences (AOOs) 16

      3. Design basis accidents (DBAs) and design extension conditions (DEC) 16

   3. Separation and independence between the RCS and shutdown systems 16

   4. Relationship of the RCS to other process systems 16

   5. Reliability 16

   6. Fail-safe design 17

   7. Reactivity control devices 18

   8. Start-up instrumentation 18

   9. Response following a reactor trip 18

   10. Reactor subcritical 19

   11. Reactor power measurement 19

   12. Human-system interface 20

   13. Testing 20

   14. Maintainability 21

   15. Foreign material management 21

   16. Electrical power and instrument air systems 21

   17. Standards for pressure-retaining systems and components 21

   18. Standards for instrumentation and interconnections 22

   19. Equipment qualification 22

       1. General 22

       2. Environmental qualification 22

       3. Seismic qualification 22

       4. Ageing management 22

   20. Digital items 23

   21. Cyber security 23

   22. Control stability 23

   23. Chemistry 23

Annex A (informative) — Guidance on control logic implementation 25

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

R. K. Black TC Energy,

Toronto, Ontario, Canada

Category: Service Industry

Chair

B. J. Coulas Kincardine, Ontario, Canada

Category: General Interest

Vice-Chair

M. Kattan Mississauga, Ontario, Canada

Category: General Interest

Vice-Chair

A. Au Ontario Power Generation, Pickering, Ontario, Canada

Category: Owner/Operator/Producer

M. Borairi Candu Energy Inc., Mississauga, Ontario, Canada

Non-voting

M. Buckler Bruce Power,

Tiverton, Ontario, Canada

Non-voting

J. R. Burnett RCM Technologies Canada Corp., Pickering, Ontario, Canada Category: Service Industry

Q. B. Chou Canadian Power Utility Services Ltd. (CPUS), Toronto, Ontario, Canada

Category: Service Industry

J. Coady Bruce Power L.P., Tiverton, Ontario, Canada

Category: Owner/Operator/Producer

J. M. Cuttler Cuttler & Associates Inc., Mississauga, Ontario, Canada

Non-voting

C. M. Daniel AECOM,

Richmond Hill, Ontario, Canada

Category: Service Industry

M. Derewonko Bruce Power L.P., Tiverton, Ontario, Canada

Non-voting

I. Dimitrov Ontario Power Generation Inc., Pickering, Ontario, Canada

Non-voting

H. Gaber University of Ontario Institute of Technology (UOIT), Oshawa, Ontario, Canada

Category: General Interest

D. L. Gillard Ontario Power Generation, Oshawa, Ontario, Canada

Non-voting

J. Grava CANTECH Associates Ltd., Annan, Ontario, Canada Category: General Interest

S. Hilts Bruce Power,

Tiverton, Ontario, Canada

Non-voting

U. Kukreti Markham, Ontario, Canada Non-voting

W. K. Lam Ontario Ministry of Energy, Northern Development and Mines,

Toronto, Ontario, Canada

Category: Government and/or Regulatory Authority

E. Lemoine Canadian Nuclear Safety Commission (CNSC), Ottawa, Ontario, Canada

Category: Government and/or Regulatory Authority

L. Luckhardt Baker Hughes, A GE Company, Dundas, Ontario, Canada

Category: Supplier/Fabricator/Contractor

J. Miller Ontario Power Generation, Pickering, Ontario, Canada

Non-voting

S. Miller Bruce Power,

Tiverton, Ontario, Canada

Non-voting

G. Mirzaei SNC-Lavalin Nuclear Inc., Mississauga, Ontario, Canada

Category: Supplier/Fabricator/Contractor

C. Moore NB Power Nuclear,

Fredericton, New Brunswick, Canada

Category: Owner/Operator/Producer

B. Nangia Nuclear Promise X (NPX), Mississauga, Ontario, Canada

Non-voting

S. Ostrowski Bruce Power,

Tiverton, Ontario, Canada

Non-voting

H. Payne BWXT Nuclear Energy Canada Inc., Peterborough, Ontario, Canada

Category: Supplier/Fabricator/Contractor

A. Persaud Canadian Nuclear Safety Commission (CNSC), Ottawa, Ontario, Canada

Non-voting

G. Sutton Canadian Nuclear Laboratories Limited (CNL), Chalk River, Ontario, Canada

Category: Owner/Operator/Producer

B. Willemsen NB Power Nuclear Corporation, Fredericton, New Brunswick, Canada

Non-voting

D. Mendolia CSA Group,

Toronto, Ontario, Canada

Project Manager

Subcommittee on Requirements for Reactor Control Systems of Nuclear Power Plants

M. Borairi Candu Energy Inc., Mississauga, Ontario, Canada

Chair

G. C. Chun Canadian Nuclear Safety Commission (CNSC), Ottawa, Ontario, Canada

B. J. Coulas Kincardine, Ontario, Canada

J. M. Cuttler Cuttler & Associates Inc., Mississauga, Ontario, Canada

J. Grava CANTECH Associates Ltd., Annan, Ontario, Canada

B. Latimer Bruce Power,

Tiverton, Ontario, Canada

P. Paquette Bruce Power,

Tiverton, Ontario, Canada

B. Tomczyk RCM Technologies Canada Corp., Pickering, Ontario, Canada

P. Zahedi Ontario Power Generation Inc., Pickering, Ontario, Canada

Y. Zhuang NB Power Corporation,

Lepreau, New Brunswick, Canada

D. Mendolia CSA Group,

Toronto, Ontario, Canada

Project Manager

Preface

This is the third edition of CSA N290.4, Requirements for reactor control systems of nuclear power plants. It supersedes the previous editions published in 2011 and in 1982 under the title Requirements for the reactor regulating systems of CANDU nuclear power plants. This edition addresses not only CANDU reactors but also 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. The Standard compiles good engineering practice, judgement, and experience with the various requirements of regulatory authorities.

Changes to this edition include the following:

1. updates to align with CNSC REGDOC-2.5.2, and for improved integration with industry standards;

2. updates to address design extension conditions to the extent they are applicable to reactor control systems (other requirements for beyond design basis accidents are addressed in CSA N290.16);

3. additional requirements regarding start-up instrumentation have been provided; and

4. requirements to enable a guaranteed shutdown state have been included.

   The specific objective of this Standard is to establish the minimum requirements for the design, procurement, 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 Standards provide 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 Group 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 was prepared by the Subcommittee on Requirements for Reactor Control Systems of Nuclear Power Plants, under the jurisdiction of the Technical Committee on Reactor Control Systems, Safety Systems, and Instrumentation for Nuclear Power Plants, and the Stategic Steering Committee on Nuclear Standards, and has been formally approved by the Technical Committee.

   Notes:

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

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CSA N290.4:19

Requirements for reactor control systems of nuclear power plants

1. Scope

   
   

   1.1

   This Standard specifies requirements for the reactor control system (RCS) of water-cooled nuclear power plants (NPPs).

   
   

   1.2

   This Standard pertains to all components of the RCS, including mechanical, process, digital items, electrical, and instrumentation and control design used for the control of the neutron flux and the thermal power of the reactor.

   Note: Moderator purification systems which can be used to control flux are excluded from the scope of this Standard.

   
   

   1.3

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

   
   

   1.4

   In this Standard, “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 (non-mandatory) to define their application.

   
   

2. Reference publications

This Standard refers to the following publications, and where such reference is made, it shall be to the edition listed below, including all amendments published thereto.

CSA (Canadian Standards Association)

N285.0-17/N285.6 Series-17

General requirements for pressure-retaining systems and components in CANDU nuclear power plants/ Material Standards for reactor components for CANDU nuclear power plants