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Position of Non-destructive testing Personnel for Application of the 'Operation' order for Nuclear Power Plants Pierre-Henri SERMADIRAS, Joseph SAMMAN Electricité de France Laboratories Group Contact

1. PURPOSE

The purpose of this presentation is to demonstrate how a specific activity like the activity carried out for the purposes of maintenance of In-service Nuclear Power Plants (CENE), can fully respect all aspects of requirements of the European directive on pressure vessels and national requirements (November 10 1999 operations order related to monitoring of the main primary circuit and the main secondary circuits in pressurized water nuclear reactors), and also the requirements of standard EN 473 (and obviously standard ISO 9712).

2. WHY THIS SPECIFIC NATURE?

2.1. History
EDF considered that certifications pronounced by the COFREND (French Confederation for Non-Destructive Testing) actually satisfied EDF requirements for the qualification and certification of non-destructive testing personnel in the best possible manner, and are necessary but not sufficient considering the development of nuclear power plants.

The specific nature of inspection procedures related to the degradation being searched for, the operator's isolation in the reactor building due to dosimetry problems, and the need to make a fast decision about the examined material to avoid extending shutdown durations, make it necessary for EDF to make sure that:

1. the operator understands the requirements of specific procedures,
2. he is capable of making a decision about the results of the exam (in-service monitoring),
3. he is capable of correctly reporting the conclusions in reports (analysis of results),
4. the inspections carried out in a hostile environment are reliable, while controlling work times.

Therefore EDF, in agreement with the safety authority (mainly the BCCN), asked the COFREND, an authorized independent body, to create a special certification for inspectors working on maintenance in its power plants. This mission was assigned to the CPSC Multi-sectorial Certification Committee that created the CENE subsector.

2.2 Scope of the CENE
The scope of activities covered by the CENE includes essentially equipment covered by the "CPP-CSP operations" order dated 10.11.1999.

The inspections concerned include all inspections starting from and including the complete initial and point zero inspection, excluding the end of manufacturing inspection. They must take account of procedures, standards in force, and particularly the RSE-M (In-service inspection rules for the mechanical components of PWR nuclear islands).

2.3 Training
Operators responsible for carrying out these inspections have previously been trained by their employers, with the purpose of:

1. improving the quality and reliability of the results in order to respect safety rules (the CENE is the only sector in which expertise in monitoring and/or the development of defects is required),
2. incorporating operating experience.

This training, based on professional experience, is additional to the basic knowledge already acquired within the scope of standard EN 473, setting down details of the following points:

1. knowledge of equipment and circuits in PWR power plants,
2. physical additions related to the methods used,
3. knowledge and control of tools associated with the inspections,
4. knowledge of the French regulations specific to the nuclear industry, codes, procedures and operating conditions specific to the maintenance of power plants,
5. methodology for the analysis, interpretation and writing of reports, with the use of processing software that uses a technology as advanced as the technology used for medical applications.

2.4 Applications
At the present time, the following inspection methods and options are subject to CENE certification (however other options may be added if necessary):

1. option 1 ET-SG: eddy current testing of steam generator tubes,
2. option 3 UT-MIS: ultrasonic testing of reactor vessels using an In-Service Inspection Machine,
3. option 4 UT-TRA: ultrasonic testing using traditional means (other than an In-Service Inspection Machine),
4. option 5 LT-SG: helium leak testing of steam generator tubes,
5. option 7 RT: radiographic testing.

In general, regardless of the option considered, the objective of the practical part of the examination is to simulate exactly what is expected from an inspector in carrying out his business.

Only COFREND certified candidates (" basic " certification in the method concerned) are eligible for options 4 (UT-TRA) and 7 (RT).
The certification examination is a complement specific to the basic examination.

However, all certified or uncertified candidates are eligible for options 1 (ET-SG), 3 (UT-MIS) and 5 (LT-SG) that are specially adapted to EDF's needs, provided that they satisfy the training and professional experience prerequisites.
This eligibility of uncertified candidates was necessary to enable operators familiar with only some of the methods applicable to these techniques, to apply for a complete certification exam that satisfies the requirements in standard EN 473. For example, an eddy current - SG analyst who has no experience in low frequency material sorting; a focused ultrasonic analyst does not use manual ultrasonic testing.
However, the corresponding certifications will only entitle the operator to work in the CENE subsector.

3. ELIGIBILITY CONDITIONS FOR THE QUALIFICATION EXAMINATION

3.1. Level 2


3.1.1 COFREND certified candidates
The qualification examination is available to:

1. operators with level 2 certification in the method
2. operators with level 3 certification in the method capable of justifying a prior level 2 certification.

3.1.1.1Training duration and required experience
The following table defines minimum required training durations and experience acquired before the qualification examination.
The specific training concerns the inspection method(s) adapted to maintenance of nuclear power plants.

Experience means experience obtained in carrying out inspections in the field of maintenance of nuclear power plants, with the candidate working under the responsibility of an inspector with a level 2 or 3 certification in the same method.

Inspection method and option	CENE specific training (2)	Minimum experience in working time
		Work during unit shutdown
(1) ET-SG	40 h	60 days
(3) UT-MIS	40 h	(1) 5 operations
(4) UT-TRA	40 h	60 days
(5) LT-SG	40 h	(3) 5 operations
(7) RT	40 h	60 days



1. Work during unit shutdown covers all activities carried out during a Complete Initial Inspection (VCI), Complete Inspection (VC), Partial Inspection (VP) and maintenance inspection, and all calibration operations on the expertise stand and qualification operations in a real or simulated environment.
2. 40 hours are equivalent to the duration of the legal working week.
3. "Operation" means participation in all activities carried out for inspection of an SG.
   Two operations may be replaced by calibration operations on the expertise stand and qualification operations in a real or simulated environment.

3.1.2 Non COFREND certified candidates
All operators are eligible for the qualification examination, but only for options 1, 3 and 5.

3.1.2.1Training duration and required experience
The following table defines the minimum required durations of the basic training in the methods, training specific to the CENE subsector, and experience acquired before the qualification examination.

Method and option	General training(in hours) (2)		CENE specific training (2)(in hours)	Inspection experience(in months)	Work during unit shutdown (in days)
	Theoretical	Practical
(1) ET-SG	24	16	40	12	60
(5) LT-SG	40	40	40	12	(3) 5 operations
(3) UT-MIS	40	40	40	12	(1) 5 operations



1. Work during unit shutdown covers all activities carried out during a Complete Initial Inspection (VCI), Complete Inspection (VC), Partial Inspection (VP) and maintenance inspection, and all calibration operations on the expertise stand and qualification operations in a real or simulated environment.
2. 40 hours are equivalent to the duration of the legal working week.
3. "Operation" means participation in all activities carried out for inspection of an SG.
   Two operations may be replaced by calibration operations on the expertise stand and qualification operations in a real or simulated environment.

3.2. Level 3


3.2.1Required experience


All operators are eligible for the qualification examination.
The following table defines minimum durations required for the experience acquired before the CENE subsector qualification examination.

Minimum experience requirements for the basic certification must include the following specific requirements:

Method and option	Work during unit shutdown
	CENE level 2 certified	CENE level 2 non-certified
(1) ET - SG	30 days	90 days
(3) UT - MIS	3 operations	(1) 8 operations
(4) UT - TRA	30 days	90 days
(5) LT - SG	3 operations	(2) 8 operations
(7) RT	30 days	90 days



1. Work during unit shutdown covers all activities carried out during a Complete Initial Inspection, Complete Inspection, Partial Inspection and maintenance inspection, and all calibration operations on the expertise stand and qualification operations in a real or simulated environment.
2. "Operation" means participation in all activities carried out for inspection of an SG.

Two operations may be replaced by calibration operations on the expertise stand and qualification operations in a real or simulated environment.

4. QUALIFICATION EXAMINATIONS

4.1. Practical methods
The requirements are identical to CPSC requirements.

4.2. Contents of the qualification examination


4.2.1. Level 2
The general and specific examination are written. The practical examination is adapted to test the candidate's capability to use reference procedures, subsequent to data acquisitions made by himself or stored on different media types (films, magnetic tapes, optical disks, etc...).

4.2.1.1- COFREND certified candidates


General examination
The candidate keeps the benefit of the general examination valid for all industrial sectors

Specific examination
Questions are chosen from a collection of specific questions defined by the C.P.S.C.
Some of the questions are multiple choice questions and others require a written reply, as defined in the following table:

Option	Multiple Choice	Require written reply
(1) ET-SG; (3) UT-MIS; (4) UT-TRA; (7) RT	22	8
(5) LT-SG	30	10

Practical examination


• Eddy current testing (option 1)
  Signal interpretation and analysis on different recording media (paper, magnetic, optical). Signals and signatures output from different indication families.
• "MIS" ultrasonic testing (option 3)
  Signal interpretation and analysis on different media (paper, magnetic, optical). Indication signals output from different configurations or families.
• Ultrasonic testing - other applications (option 4)
  Search for indications and reports in accordance with procedures used in nuclear power stations (in two areas) distributed on one or two documents, update the reference file.
• "SG tube" leak testing (option 5)
  Check the leak testing of a part using the He method, interpretation of the recording, analysis and report writing.
• Radiographic testing (option 7)
  Knowledge of tools. Questions on 10 views of tools.
  Read and interpret 10 radiograms, including 1 sampling for comparative reading.
  Recognition of conformity on 5 radiograms.

The concept of the practical test depends in particular on the number of listed defects detected by the candidate, the accuracy of their evaluation, and the quality of report writing.

4.2.1.2- Non COFREND certified candidates
This examination is organized like a Multisectorial Committee qualification examination. The specific and practical examinations are adapted to the CENE subsector.

General examination
The method used for this examination is identical to the method used for the general examination.

Specific examination
Questions are chosen from a collection of specific questions defined by the C.P.S.C.
Some of the questions are multiple choice questions and others require a written reply, as defined in the following table:

Option	Multiple Choice	Require written reply
(1) ET-SG; (3) UT-MIS	22	8
(5) LT-SG	30	10

Practical examination
Identical to the qualification examination for COFREND certified candidates in the CENE option considered.

4.2.2. Level 3


4.2.2.1- COFREND certified candidates


General examination
The candidate keeps the benefit of the general examination valid for all industrial sectors

Specific examination
20 questions:

1. 10 multiple choice questions
2. 10 requiring written replies

These questions are chosen from a collection of specific questions prepared by the C.P.S.C.

Practical examination


• Options 1, 3, 4 and 7
  In addition to requirements for level 2 candidates, a level 3 candidate must carry out work on the analysis, diagnostic consistency, and comparison of inspection results obtained during successive operations.
  Furthermore, he must write a document corresponding either to a particular procedure or to a specific operating method.
• Option 5 (S.G. leak testing.)
  The test is similar to a level 2 examination, but is more difficult.
  Furthermore, the candidate must write a document corresponding either to a particular procedure, or to a specific operating method.

4.2.2.2- Non COFREND certified candidates
In accordance with the general procedure, the candidate must have carried out the following tests:

1. Level 2 practical examination in the method,
2. Basic examination,
3. General examination.

The tests corresponding to the subsector examination are as described in §4.2.2-1.

5. CERTIFICATION AND PERFORMANCE DEMONSTRATION

Since the end of 1998 EDF put in place an organization for qualification of NDE applications in accordance to the RSEM 97 Code. The object is to verify by tests and by technical justification files that such NDE application is able to detect and size correctly not tolerated defects in the main components (see § 2.2), with sufficient margin to safety requirements.

The methodology applied follows in general the recommendations of the ENIQ (European Network for Inspection Qualification), in which EDF was a very active member.

For the nature (stress corrosion, fatigue, hydrogen induced, irradiation assisted.....cracks) and size of the defects to be detected, the requirements are written down by EDF technical department and submitted for agreement to the French Safety Authority.

For personnel qualification it doesn't require that open or blind tests should be performed by all the operators, but only by a representative team. In other hand it requires that all the operators who will perform the qualified ISI application should be trained to the specific procedure like the representative team and certified by CENE subsection (see § 2.4).

A team of NDE and Quality Assurance experts from EDF and French industry, organized as «a second independent party» assess the qualification and deliver the certificates.

6. CONCLUSIONS

In two recently processed examples (inspection of the core region of the Reactor Pressure Vessel and searching thermal fatigue cracks in stainless steel piping ), the personnel qualification was based on CENE certified analysts (UT-MIS) or operators (UT-TRA) specially trained to the specific procedure. This was considered as satisfying the new Operations Order.

For other applications in the future, a CENE certification with additional particular modules or options, could be added and must result in permanent personnel qualification in this subject.

List of CENE certified operators valid on 31.12.1999

Level 2 (EDF and Service providers)


Option Company	ET-SG	LT-SG	RT	UT	UT MIS	Total
GDL	19	1	18	14	2	54
Service Providers	116	19	144	149	9	437
TOTAL	135	20	162	163	11	491

Level 3 (EDF and Service Providers)


Option Company	ET-SG	LT-SG	RT	UT	UT MIS	Total
GDL	4	1	1	1	1	8
Service Providers	3	7	3	7	2	22
TOTAL	7	8	4	8	3	30

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