MDEP Generic Common Position

Multinational Design Evaluation Programme
Generic Common Position
DICWG No11 – PUBLIC USE

Date: 11 December 2013
Validity: until next update or archiving
Version E

MDEP GenericCommon Position
No DICWG-11
Related to: Digital Instrumentation and Controls Working Group activities

COMMON POSITION ON DIGITAL I&C SYSTEM
PRE-INSTALLATION AND
INITIAL ON-SITE TESTING

1MDEP Generic Common Position

Multinational Design Evaluation Programme
Generic Common Position
DICWG No11 – PUBLIC USE

Date: 11 December 2013
Validity: until next update or archiving
Version E

ParticipationCountries involved in the MDEP working group Canada, Finland, France, India, Japan, People’s
discussions:
Republic of China, Republic of Korea, RussianFederation, South Africa, Sweden, the U.A.E., theU.K. and the U.S.
Countries which support the present common Canada, Finland, France, India, Japan, People’s
position
Republic of China, Republic of Korea, RussianFederation, South Africa, Sweden, the U.A.E., theU.K. and the U.S.
Countries with no objection:
Countries which disagree
Compatible with existing IAEA related documents
Yes2MDEP Generic Common Position

Multinational Design Evaluation Programme
Generic Common Position
DICWG No11 – PUBLIC USE

Date: 11 December 2013
Validity: until next update or archiving
Version E

Multinational Design Evaluation Programme
Digital Instrumentation and Controls Working Group

GENERIC COMMON POSITION DICWG NO11: COMMON POSITION ON DIGITAL I&C
SYSTEM PRE-INSTALLATION AND INITIAL ON-SITE TESTING

Summary:
The Digital Instrumentation and Controls Working Group (DICWG) has agreed that acommon position on this topic is warranted given the increased use of Digital Instrumentation andControl (I&C) in new reactor designs, its safety implications, and the need to develop a common
understanding from the perspectives of regulatory authorities. This action follows the DICWG
examination of the regulatory requirements of the participating members and of relevant industry
standards and IAEA documents. The DICWG proposes a common position based on recent
experience with the new reactor application reviews and operating plant issues1.
Context:
Pre-installation tests and initial on-site tests are important stages within the life cycle ofdigital I&C systems. These tests confirm that the digital I&C systems comply with theirrequirements and help ensure Nuclear Power Plant (NPP) correct performance under plant states
as per safety analysis.
Note: Plant states in the context of this common position refer to:
Operational states: NO - normal operation; AOO - anticipated operational occurrences;
Accident states: DBA - design basis accidents; DEC - design extension conditions
Definition of terms:
Pre-installation testing
Activity to demonstrate that an I&C system or integrated set of systems are in accordance with
their specifications and to validate the systems against their requirements to the extent that this ispossible outside of the plant environment.

1The goal of MDEP is not to independently develop new regulatory standards. Common Positions are not legally binding and do
not constitute additional obligations for the regulators or the licensees but are guidelines, recommendations, or assessments that theMDEP participants agree are good to highlight during their safety reviews of new reactors. Any MDEP member may decide toimplement the common positions through its national regulatory process.

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MDEP Generic Common Position

Multinational Design Evaluation Programme
Generic Common Position
DICWG No11 – PUBLIC USE

Date: 11 December 2013
Validity: until next update or archiving
Version E

Initial on-site testing
Activity to demonstrate that the installation of the various I&C systems are in accordance with theapplicable specifications and installation instructions and to validate the systems against theirrequirements within the plant environment under all relevant plant operational states. Within thecontext of this common position, test activities include testing prior to fuel load, post fuel load,
post-criticality and up to full power. Periodic operational testing is outside the context of thiscommon position.
Validation

The process of determining whether a product or service is adequate to perform its intended
function satisfactorily [IAEA glossary ed.2007].
Commissioning
Process during which NPP components and systems, having been constructed, are madeoperational and verified to be in accordance with design assumptions and to have met theperformance criteria; it includes both non-nuclear and nuclear tests [IEC 61513].
Generic Common Position on pre-installation and initial on-site testing
1. Testing should be performed in both pre-installation and initial on-site testing stages. The
strategy for distribution of necessary tests under different conditions should be developed at
the early design stage and documented in a validation test plan. A strategy for staggering
validation testing may include steps such as:
 conduct simulation/emulation tests of safety algorithms,
 conduct first set of validation tests during pre-installation,
 conduct second set of validation tests during the initial on-site testing on site.
2. Testing scenarios should address all relevant events based on the plant safety analysis.
3. All test results should be documented and processed in accordance with applicableprocedures.
4. Changes to design documents and procedures, and other information relevant to I&C systems,
resulting from all testing activities should be documented in accordance with requirements forconfiguration control.
5. The following should be included in the pre-installation testing stage:
5.1 Verify that results from previous stages of the digital I&C systems life cycle arecomplete and that open items are resolved and closed.
5.2 Verify that system components, application software, and subsystems have been properlyconfigured.
5.3 Verify that the system hardware and software are properly integrated in accordance withI&C design specification and final assembly configuration.
4MDEP Generic Common Position

Multinational Design Evaluation Programme
Generic Common Position
DICWG No11 – PUBLIC USE

Date: 11 December 2013
Validity: until next update or archiving
Version E

5.4 Perform pre-installation testing in accordance with test procedures which include
defined acceptance criteria.
5.5 Test system behaviour by conducting static and dynamic simulations of the plant asappropriate. These tests help validate the correctness of the system design.
5.6 Test results should be used to help confirm system response to potential internal faults(e.g., hardware, data communication links, loss of internal power supply).
5.7 Test results should be used to help confirm system response to potential external faults
and abnormal behaviour of external systems (e.g., interfaces, loss of external power
supply, electro-magnetic interferences, loss of heating, ventilation and air conditioning,abnormal voltage and frequency variations).
5.8 Test all relevant digital I&C system requirements (including other performancerequirements and quality of service characteristics) that can be performed at this stage.
These tests should also address relevant requirements for human factor considerations.
5.9 Test for potential systematic design vulnerabilities. Examples of such tests include:
processor stress test, stability tests.
5.10 Confirm that analysis or inspections are provided to complement testing as appropriate
to justify conformance to system requirements and performance.
5.11 Ensure the equipment used for test is properly calibrated and configured.
5.12 Credit may be taken for pre-installation test results of replicated I&C systems, includingthose used in multiple NPP units, as long as equivalency is demonstrated and operabilityof hardware and correctness of software loading is confirmed. Any deviation from thereplication should be verified and their impact fully assessed.
6. The following should be included in the initial on-site testing stage:
6.1 Perform initial on-site testing in accordance with test procedures with defined acceptancecriteria
6.2 Verify that the system delivered on site corresponds with the system tested during preinstallation test.
6.3 Verify that the system meets its functional and performance requirements that were notverified during pre-installation testing. Tests performed during pre-installation testingneed not be fully repeated during initial on-site testing if test equivalence can bedemonstrated.
6.4 Before digital I&C systems are declared fully operational, perform the following

activities:
6.4.1 Test all interfaces (e.g., assessment of accuracy of plant response to system
actuation, accuracy of providing information to operating personnel, accuracy ofinformation being archived).
6.4.2 Confirm that environmental conditions, including electromagnetic conditions, arecompatible with correct operation of digital I&C equipment.
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MDEP Generic Common Position

Multinational Design Evaluation Programme
Generic Common Position
DICWG No11 – PUBLIC USE

Date: 11 December 2013
Validity: until next update or archiving
Version E

6.4.3 Verify that the I&C design principles (e.g. redundancy, independence, diversity,protection against CCF, implementation of defense in depth) are correctly
incorporated as part of the overall I&C systems integration.
6.4.4 Verify the physical installation of the I&C systems.
6.4.5 Verify the installation of I&C systems against NPP site specific design
characteristics.
6.4.6 Confirm integration of I&C systems and human machine interfaces performanceof the Main Control Room and supplementary control rooms.
6.5 Perform all initial on-site test activities that should be done prior to fuel load to confirm
integrity and operability of digital I&C systems. After fuel loading, perform theremaining initial on-site test activities whose testing requires loaded fuel (e.g., calibrationof neutron flux measurement channels).
6.6 Confirm that initial on-site tests address the relevant principles and objectives defined inthe commissioning programme, including a step by step approach to full power.
6.7 All test results should be documented and processed in accordance with applicableprocedures.
References

Seven party report titled “Licensing of safety critical software for nuclear reactors".
Common position of seven European nuclear regulators and authorised technical supportorganizations.

Four Party Regulatory Consensus Report On The Safety Case For Computer-Based
Systems In Nuclear Power Plants, November 1997.

IEC 61513 Rev.2 2011-08.

IAEA NS-G-2.9

IAEA SSR 2/1



IAEA Safety Glossary Terminology Used in Nuclear Safety and Radiation Protection,
Edition 2007.

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