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1
NRC Perspective on ASME
NDE Certification Process
Aladar Csontos, Wallace Norris, Carol Nove
NRC/RES/DE/CIB
Michael Anderson & Steven Doctor
PNNL
May 9, 2011
Outline
• Regulatory Requirements
• Appendix VII
• Appendix VIII
• Where are we today?
• Areas of Improvement
• ANDE Program
• NRC Feedback to ANDE
• Conclusion
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Regulatory Requirements
• Appendix A to Part 50: GDC-1 for NPP – Overall Requirements
– Criterion 1—Quality standards and records - Structures, systems, and
components important to safety shall be designed, fabricated, erected,
and tested to quality standards commensurate with the importance of
the safety functions to be performed. Where generally recognized
codes and standards are used, they shall be…evaluated to determine
their…adequacy, and sufficiency and shall be supplemented or modified
as necessary to assure a quality product in keeping with the required
safety function.
• Appendix B to Part 50--Quality Assurance Criteria for Nuclear Power
Plants and Fuel Reprocessing Plants
– IX. Control of Special Processes - Measures shall be established to
assure that special processes, including welding, heat treating, and
nondestructive testing, are controlled and accomplished by qualified
personnel using qualified procedures in accordance with applicable
codes, standards, specifications, criteria, and other special
requirements.
Regulatory Requirements (cont.)
• 10 CFR 50.55(a)(b) incorporates by reference the ASME Code,
Section XI, Rules for Inservice Inspection of Nuclear Power Plant
Components.
• Section XI, Appendix VIII, Performance Demonstration for
Ultrasonic Examination Systems, was first approved when the NRC
incorporated the 1995 Edition with the 1996 Addenda into 10 CFR
50.55a
• 10 CRF 50.55(a)(b)(2)(xiv) addresses Appendix VIII personnel
qualification and requires that all personnel qualified for performing
ultrasonic examinations in accordance with Appendix VIII shall
receive 8 hours of annual hands-on training on specimens that
contain cracks. This training must be completed no earlier than 6
months prior to performing ultrasonic examinations at a licensee's
facility.
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How do we assure that the “special
process” of nondestructive testing
is controlled and accomplished by
qualified personnel using qualified
procedures in accordance with the
applicable codes, standards,
specifications, criteria and other
special requirements?
Appendix VII
• ASME Code, Section XI, Appendix VII – Qualification of
Nondestructive Examination Personnel for Ultrasonic
Examination
– Requires that the skills and responsibilities associated
with each level of qualification be defined by
ANSI/ASNT-CP-189, Standard for Qualification and
Certification of Nondestructive Testing Personnel.
– Specifies requirements for employer certification of
personnel including required experience for initial
certification
– Allows use of outside agency to provide NDE Level III
or NDE Instructor services
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Appendix VIII
• ASME Code, Section XI, Appendix VIII, Performance
Demonstration for Ultrasonic Examination Systems,
published in the 1989 Edition and 1989 Addenda.
• Provides requirements for performance demonstrations
for ultrasonic examination procedures, equipment, and
personnel used to detect and size flaws.
• In contrast to prescriptive requirements, Appendix VIII
allowed any combination of procedures, equipment
and personnel to be used for ISI as long as the
combination could pass a statistically designed
performance demonstration blind test on
representative mockups containing realistic flaws.
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Implementation of
Appendix VIII
• The Performance Demonstration Initiative (PDI) was
formed and funded by the U.S. utilities in 1991 to
implement the performance demonstration requirements
of Appendix VIII.
• PDI is administered by the Electric Power Research
Institute (EPRI).
• Implementation of Appendix VIII through PDI has greatly
enhanced the reliability of ultrasonic examinations of
welds in primary reactor systems
• Appendix VIII references Appendix VII for the
qualification of personnel performing ultrasonic
examinations.
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Where are we today?
• Certification is employer based – varies from employer to
employer
• Training requirements -
– Only 8 hours of semi-annual practice required once
certification achieved
• To address the shortage of qualified inspectors, ASME
actions, such as Code Case N-784, Experience Credit for
Ultrasonic Examiner Certification, have been introduced
– CC N-784 reduces the number of hours required for
certification to Level II and substitutes laboratory practice for
field experience
– CC N-784 is limited with regard to its objectives - The NRC
staff believes a more comprehensive approach is required to
address the issues associated with personnel qualification.
9
Where are we today?
Appendix VIII
• Has improved ability to detect and characterize service-
induced flaws in critical primary reactor systems
• Is a screening test that was developed to eliminate poor
performing combinations of procedures, personnel and
equipment, and to validate the training, knowledge, and
skills needed through performance
– passing/failing determined by combination of
detection tests (POD) coupled with false call rates
– length and depth sizing must fall within the
acceptance criteria provided by each of the
applicable Appendix VIII supplements
• Qualification data is wealth of untapped information.
10
Where are we today?
• All personnel who take Appendix VIII qualification
exams are certified by their employer to the ANSI/ASNT
CP-189 standard.
– Huge variations in personnel capabilities exist due to
lack of process standardization
– Critical thinking skills/understanding of the
physics/materials/defects involved often missing,
resulting in lack of ability to assess field situations,
apply appropriate technique and interpret the UT
data
– Need to implement training on flaw discrimination
• Appendix VIII does not require requalification of
personnel after initial qualification.
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Where are we today?
• PDI mockups typically do not include weld fabrication flaws.
Use of these mockups may result in:
– the inability of qualified inspectors to distinguish service-
induced flaws from fabrication flaws
– qualifying personnel on flaws that do not adequately represent
the flaws found in the field
• The POD for qualification exams may be artificially high relative to
what it would be if real flaws in realistic mockups were used.
• Blank and flawed grading units with little potential for false calls
are selected to enhance the ability of the Performance
Demonstration Administrator (PDA) to conduct examinations.
Therefore, personnel may have limited opportunity to make false
calls during testing. 12
NRC
Concerns
Areas of Improvement
Where does NRC see room for improvement?
• Revisions to Appendix VII –
– any reduction in experience requirements for certification
must have an adequate, perhaps performance, basis
– only limited ability to substitute laboratory hours for field
experience
– more consistent application of training and examination
requirements
• Revisions to Appendix VIII –
– more real flaws and realistic conditions (i.e., inclusion of
fabrication flaws) in mockups
– requalification requirements
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Areas of Improvement
Where does NRC see room for improvement? (cont.)
• PDI program –
– analysis (with regulatory oversight) of the qualification data
to assess original assumptions used during development
of Appendix VIII, to determine how well the population of
examiners is actually performing during qualification
exams, to guide future mockup fabrication practices, and
generally shore up weaker areas of the program.
• Issues with Qualification to be addressed –
– Revise and/or implement certification (including recertification)
program that focuses on performance demonstration for NDT
– NRC supports EPRIs recent efforts to implement a program to
ensure maintenance of skills
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ANDE Program
NRC supports the ANDE Program…
• ANDE broadens discussion to include the entire range
of NDE methods typically used at NPPs.
• ANDE may possibly improve personnel qualifications
across the board by providing a consistent certification
process that removes the employer to employer
variability.
• Central certification may result in more qualified
personnel in the NDE pipeline. Personnel with new
certification will be able to move between employers.
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ANDE Program
NRC supports the ANDE Program…(cont.)
• Job Task Analyses can potentially provide a
meaningful basis for a consistently applied qualification
process.
• The administration of written and practical exams by an
independent third party provides the foundation for
standardizing the exam process, enhancing program
integrity and auditability.
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NRC Feedback to ANDE
• NRC would like to see the Committee
Membership represent a balance of all
interested sectors to ensure that ASME NDE is
accepted by the whole NDE community -
– Committee is heavily weighted towards
manufacturers and utilities
– NRC would like to see broader involvement from all
other interested parties including academic and
other NDE sectors
– Inclusive rather than exclusive
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Conclusion
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• NRC looks to ANDE to provide assurance
that certified personnel have
demonstrated, via appropriate training,
experience and testing, a given level of
knowledge and the ability to successfully
apply the knowledge for the various NDE
methods used in NPPs…
performance demonstration for
all NDE methods.
(Qualification for
other NDE methods)
• For in-service inspection, personnel qualification
requirements are found in the ASME Code, Section XI,
IWA-2300 “Qualifications of Nondestructive
Examination Personnel.”
– In accordance with ANSI/ASNT CP-189
• For new construction, personnel qualification
requirements are found in Section III, NB-5500,
“Qualifications and Certification of Nondestructive
Personnel.”
– In accordance with SNT-TC-1A
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(What did we do prior
to Appendix VIII?)
• Prior to 1989, UT requirements in Section XI based on prescriptive
procedures for ISI and PSI -
– amplitude-based methods, calibrated from machined reflectors
– did not provide adequate detection for real flaws because real
flaws do not behave like machined reflectors
• Specifying changes to existing procedures would not result in the
level of improvement desired
• More stringent qualification of the UT techniques through
personnel training and performance demonstration was necessary
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Appendix VII &
Appendix VIII
Recommended