CSA N290.11:21

Requirements for reactor heat removal capability during outage of nuclear power plants

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  CSA N290.11:21

  July 2021

  
  

  Title: Requirements for reactor heat removal capability during outage of nuclear power plants

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CSA N290.11:21

Requirements for reactor heat removal capability during outage of nuclear power plants

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ICS 27.120

ISBN 978-1-4883-3631-7

© 2021 Canadian Standards Association

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

Contents

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

Subcommittee on Requirements for Reactor Heat Removal Capability during Outage of Nuclear Power Plants 5

Preface 6

1. Scope 8

   
   

2. Reference publications 9

   
   

3. Definitions 10

   1. Definitions 10

   2. Abbreviations 12

      
      

4. Functional requirements 12

   1. General 12

   2. Success criteria 13

      1. Process heat sinks 13

      2. Emergency heat sink 13

         
         

5. Heat sink requirements 13

   1. General 13

   2. Heat sink operation 15

      1. General 15

      2. Recall 15

      3. Actions on failure of a heat sink 16

      4. Heat sinks affecting other work 17

      5. Monitoring 17

   3. Instrumentation and control 17

   4. Loop isolation 18

      1. General 18

      2. Loop isolation for reactors with two cooling loops in the reactor coolant system 18

   5. Reliability 18

      1. General 18

      2. Redundancy 19

      3. Diversity 19

   6. Independence and separation 19

      1. Process heat sink independence 19

      2. Emergency heat sink independence 20

      3. Separation 20

   7. Equipment qualification 20

      1. Process heat sink 20

      2. Emergency heat sink 20

      3. Seismic qualification 20

      4. Aging 21

   8. Dynamic piping effects 21

   9. Maintenance 21

      1. General 21

      2. Maintenance on the primary heat sink 21

      3. Maintenance on the standby components of the process heat sink 21

      4. Maintenance on the emergency heat sink 22

      5. Maintenance program 22

   10. Functional testing 22

   11. Documentation 22

   12. Heat sink support system requirements 23

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

L. C. Luckhardt Baker Hughes — Dresser, Dundas, Ontario, Canada Category: Service Industry

Chair

N. Mesmous Canadian Nuclear Safety Commission (CNSC), Ottawa, Ontario, Canada

Category: Government and/or Regulatory Authority

Vice-Chair

R. Clavero Kinectrics Inc.,

Toronto, Ontario, Canada

Category: Service Industry

Vice-Chair

M. Buckler Bruce Power,

Tiverton, Ontario, Canada

Non-voting

B. Chan Technical Standards & Safety Authority, Toronto, Ontario, Canada

Category: Government and/or Regulatory Authority

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

Non-voting

D. Garrick Canadian Nuclear Laboratories Limited (CNL), Chalk River, Ontario, Canada

Category: Owner/Operator/Producer

S. Gateman Bruce Power,

Tiverton, Ontario, Canada

Non-voting

L. Gilbert Bruce Power,

Tiverton, Ontario, Canada

Category: Owner/Operator/Producer

S. Gyepi-Garbrah Canadian Nuclear Safety Commission (CNSC),

Ottawa, Ontario, Canada

Non-voting

R. Henry Kinectrics Inc.,

Toronto, Ontario, Canada

Non-voting

R. Ion MeV200 Consulting Inc., Mississauga, Ontario, Canada

Non-voting

W. K. Lam Toronto, Ontario, Canada

Category: Government and/or Regulatory Authority

P. Lawrence Kinectrics Inc.,

Pickering, Ontario, Canada

Non-voting

C. Lorencez Candu Owners Group, Toronto, Ontario, Canada Category: General Interest

J. Luxat McMaster University, Hamilton, Ontario, Canada Category: General Interest

D. Mullin NB Power Corporation,

Lepreau, New Brunswick, Canada

Category: Owner/Operator/Producer

M. K. O’Neill Ian Martin Limited, Scarborough, Ontario, Canada

Non-voting

Y. Parlatan Ontario Power Generation Inc., Pickering, Ontario, Canada

Category: Owner/Operator/Producer

P. Santamaura SNC-Lavalin Nuclear Inc., Mississauga, Ontario, Canada Category: Service Industry

A. Tokuhiro Ontario Tech University, Oshawa, Ontario, Canada Category: General Interest

J. Lee CSA Group,

Toronto, Ontario, Canada

Project Manager

Subcommittee on Requirements for Reactor Heat Removal Capability during Outage of Nuclear Power Plants

M. Buckler Bruce Power,

Tiverton, Ontario, Canada

Chair

J. Johns Bruce Power,

Tiverton, Ontario, Canada

Vice-Chair

L. Gilbert Bruce Power,

Tiverton, Ontario, Canada

H. Hasanein Kinectrics Inc.,

Toronto, Ontario, Canada

R. Henry Kinectrics Inc.,

Toronto, Ontario, Canada

B. Lekakh SNC-Lavalin Nuclear Inc., Mississauga, Ontario, Canada

G. Martin Ontario Power Generation Inc. Darlington NGS, Bowmanville, Ontario, Canada

M. Ohn Canadian Nuclear Safety Commission, Ottawa, Ontario, Canada

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

J. Lee CSA Group,

Toronto, Ontario, Canada

Project Manager

Preface

This is the second edition of CSA N290.11, Requirements for reactor heat removal capability during outage of nuclear power plants. It supersedes the previous edition published in 2013.

The following are the major changes to this edition:

1. updated requirements and specifications for the back-up heat sink and the protection it is to provide;

2. provided additional clarification in areas identified by users; and

3. improved alignment with current industry standards.

   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 can provide more specific direction for those requirements.

   This Standard reflects the operating experience of the Canadian nuclear power industry.

   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 Heat Removal Capability during Outage 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 Strategic 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 N290.11:21

Requirements for reactor heat removal capability during outage of nuclear power plants

1 Scope

1.1

This Standard covers the design, qualification, installation, commissioning, operation, maintenance, testing, inspection, and documentation requirements for systems providing heat removal from the reactor core to the ultimate heat sink(s) for water-cooled nuclear power plants during outages.

1.2

This Standard covers only fuel cooling within the reactor core and does not cover spent fuel pool cooling, off-reactor fuelling operations, or the completely defuelled core state.

1.3

This Standard covers all systems that contribute to the transfer of heat by

1. conveying heat to the ultimate heat sink;

2. providing power or compressed air;

3. providing inventory makeup to heat sink systems; or

4. monitoring and control.

Note: The combination of systems or portions of systems that contribute to these functions are referred to in this Standard as “heat sinks”.

1.4

The term “outage” refers to the following reactor states:

1. a shutdown state where subcriticality is assured by physical means; or

   Note: For CANDU reactors, this refers to a guaranteed shutdown state.

2. critical or sub-critical at any power where the normal (at high power) heat sinks are not the primary heat sinks.

Note: Examples of high power heat sinks include steaming of boilers to turbine or condensers.

1.5

This Standard does not cover requirements for design extension conditions (DEC). Requirements and principles for maintaining fuel cooling for outages during DECs, including requirements for emergency cooling water and power supplies, are covered in CSA N290.16.

1.6

For the purposes of this Standard, the outage commences when the normal (at high power) heat sinks are no longer the primary heat sinks.