Ageing of instrumentation and control (I&C) equipment at nuclear facilities has the potential to degrade mechanisms, which can in turn reduce safety margins and increase operating and maintenance costs. Obsolescence of I&C equipment can compound matters as suitable replacements become difficult to source. In 2019, the IAEA Technical Working Group on Nuclear Power Plant Instrumentation and Control acknowledged that relevant system and strategy guidance was required to implement modern technology at nuclear facilities. The purpose of this publication is to assist Member States in developing strategies to address ageing and obsolescence issues for I&C systems and it provides detail on modernization considerations and information from relevant recent operator experience. An appendix summarizes cable ageing management through condition monitoring, and several annexes describe Member States’ practices and experience with l&C ageing management and modernization.

• 1. Introduction
  • 1.1. Background
  • 1.2. Objective
  • 1.3. Scope
  • 1.4. Structure
• 2. Relevant IAEA safety requirements, RECOMMENDATIONS and guidance
  • 2.1. Relevant IAEA safety requirements for managing ageing and obsolescence
  • 2.2. IAEA recommendations and guidance for managing ageing and obsolescence
• 3. ageing management OF I&C equipment
  • 3.1. Introduction: definition of ageing equipment
  • 3.2. Ageing related degradation mechanisms and effects
    • 3.2.1. Examples of ageing related degradation mechanisms
    • 3.2.2. Examples of ageing effects
  • 3.3. Methods and techniques to identify ageing I&C equipment
    • 3.3.1. Visual inspections
    • 3.3.2. Real time monitoring
    • 3.3.3. Infrared thermography
    • 3.3.4. Cable testing
  • 3.4. Ageing equipment simulation and modelling
    • 3.4.1. Ageing equipment simulation
    • 3.4.2. Ageing equipment modelling
  • 3.5. Degradation acceptance criteria
    • 3.5.1. Degradation acceptance criteria for I&C equipment (excluding cables)
    • 3.5.2. Degradation acceptance criteria for cables
  • 3.6. Ageing management of spare parts
  • 3.7. Data capture and trending
    • 3.7.1. Monitoring, recording and trending
    • 3.7.2. Data capture
    • 3.7.3. Review of data
    • 3.7.4. OPEX and solution sharing
    • 3.7.5. Use of modern digital technology
  • 3.8. General specification, design, manufacture and in-service life cycle phase considerations
    • 3.8.1. Safety case
    • 3.8.2. Specification considerations
    • 3.8.3. Design and manufacture considerations
    • 3.8.4. In-service considerations
  • 3.9. Maintenance arrangements and strategies
    • 3.9.1. Ageing related degradation mechanism training
    • 3.9.2. Proactive ageing equipment management
    • 3.9.3. Maintenance schedule considerations
    • 3.9.4. Ageing related equipment maintenance strategies
• 4. I&C equipment obsolescence management
  • 4.1. Introduction
  • 4.2. Definition and scope
    • 4.2.1. COTS products
    • 4.2.2. Custom I&C equipment
    • 4.2.3. Externally maintained I&C equipment
    • 4.2.4. I&C equipment software obsolescence
  • 4.3. I&C equipment obsolescence management process
    • 4.3.1. Overview
    • 4.3.2. Phase 1: I&C equipment identification, data collection and recording
    • 4.3.3. Phase 2: I&C equipment obsolescence status identification
    • 4.3.4. Phase 3: Prioritization of I&C equipment obsolescence issues
    • 4.3.5. Phase 4: Resolution of I&C equipment obsolescence issues
    • 4.3.6. Solution sharing
  • 4.4. Configuration management
  • 4.5. Software
    • 4.5.1. Planning for software obsolescence
    • 4.5.2. Software security
    • 4.5.3. Control of existing software for a system’s operating life
  • 4.6. Knowledge management of I&C equipment
  • 4.7. Other I&C equipment obsolescence considerations
    • 4.7.1. Monitoring and generation of useful metrics
    • 4.7.2. Obsolescence management tools and organizations
• 5. strategies FOR I&C system/equipment modernization
  • 5.1. Introduction
  • 5.2. Strategies/options
    • 5.2.1. Common information for all strategies/options
    • 5.2.2. Replacement with similar equipment (fit, form and function or like for like)
    • 5.2.3. Remanufacturing/reengineering
    • 5.2.4. Reverse engineering
    • 5.2.5. Partial and full replacement
    • 5.2.6. Joint strategies
  • 5.3. Decision making process
    • 5.3.1. Equipment availability judgements
    • 5.3.2. Operational judgements
  • 5.4. Solution justification
    • 5.4.1. Item equivalency evaluation
    • 5.4.2. Non-identical component replacement/substitution
    • 5.4.3. Engineering change process
    • 5.4.4. Assessment of security arrangements
  • 5.5. Developments in obsolescence management
• 6. I&C system/equipment modernization strategies and issues
  • 6.1. Strategies for modernization
  • 6.2. Choice of technology
    • 6.2.1. High level considerations
    • 6.2.2. Use of the same technology
    • 6.2.3. Scale of modernization
    • 6.2.4. Benefits of digital migration
    • 6.2.5. Digital technology choices
    • 6.2.6. Use of COTS equipment
    • 6.2.7. Use of wireless network technology
  • 6.3. Interfaces with existing systems/plant
  • 6.4. Replacement with similar equipment strategy
  • 6.5. Reverse engineering strategy
    • 6.5.1. Introduction
    • 6.5.2. Considerations for reverse engineering
    • 6.5.3. Conditions for reverse engineering
    • 6.5.4. Procurement, supply chain and material maintenance
  • 6.6. Partial or full replacement strategy
    • 6.6.1. Preparation
    • 6.6.2. Partial replacement modernization strategy
    • 6.6.3. Full replacement modernization strategy
  • 6.7. Modernization implementation scheduling
  • 6.8. Modernization project delivery and techniques
    • 6.8.1. Introduction
    • 6.8.2. Project scope and delivery method
    • 6.8.3. Pre-engineering phases
    • 6.8.4. Contract strategies
    • 6.8.5. Life cycle synchronization and hold points
    • 6.8.6. Design and construction
    • 6.8.7. Factory test and commissioning
    • 6.8.8. Installation
    • 6.8.9. Long term support and spares
    • 6.8.10. End stages, closeout and handover
• Appendix CABLE AGEING MANAGEMENT THROUGH CONDITION MONITORING
• REFERENCES
• Annex I UNITED KINGDOM SIZEWELL B WISCO-2 DATA PROCESSING AND CONTROL SYSTEM REPLACEMENT PROJECT
• Annex II LOVIISA ELSA PROJECT IN FINLAND
• Annex III UKRAINIAN NPP I&C MODERNIZATION PROJECTS
• Annex IV USE OF 3-D PRINTER TECHNOLOGY TO ADDRESS AN AGEING AND OBSOLESCENCE ISSUE AT THE DARLINGTON NPP
• Annex V USE OF ACCELERATED AGEING ON EQUIPEMENT IN A MILD ENVIRONMENT
• Annex VI DARLINGTON NPP LIQUID ZONE CONTROL POSITIONER REPLACEMENT
• ABBREVIATIONS
• CONTRIBUTORS TO DRAFTING AND REVIEW
• STRUCTURE OF THE IAEA NUCLEAR ENERGY SERIES