Procurement Engineering Task Team FAQ

FAQ1
CAN A DIFFERENT DEGREE OF VERIFICATION BE USED ON AN ITEM WITH EQUIVALENT SAFETY FUNCTIONS?

ANSWER

Yes, the degree of verification will vary depending on the determining factors of the technical evaluation, such as the consequence and likelihood of failure.  As in all cases when using engineering judgement, the factors considered in the technical evaluation to determine the degree of verification must be documented.

AMPLIFYING INFORMATION

Determination of the rigor utilized in the verification of critical characteristics is part of the larger determination of reasonable assurance that the item/service will perform its intended safety function (See FAQ-2 for more on reasonable assurance).  

NQA-1 Subpart 2.14 Section 601 contains discussion on the selection of acceptance method(s) for use in determining if the commercial grade item/service meets the acceptance criteria of the selected critical characteristics.

EXAMPLES

ASTM A312 304 Stainless Steel Pipe with safety function to maintain pressure boundary.

Case A – Pipe supplying coolant to spent fuel storage

Loss of spent fuel storage coolant could potentially cause fuel melting and a resulting criticality accident.  The consequences of such a failure are relatively high as it would result in a significant safety impact to co-located workers and the public.

Case B – Pipe transporting radioactive liquid

A breach in the pressure boundary could potentially result in the spray of radioactive liquid on a co-located worker. Such a failure of the pipe would result in a minor safety impact on a co-located worker. 

The pipe in both cases is neither complex nor unique, however the consequences of each pipe failure are significantly different.  Case A might require the performance of a full chemical and physical analysis of test coupons to verify conformance with the requirements of ASTM A312.  While Case B might require the performance of XRF PMI to verify conformance of the major chemical constituents (Cr and Ni) with the requirements of ASTM A312.  In each of these cases the technical evaluation leads the CGD practitioner to perform varying degrees of rigor to obtain reasonable assurance.

REFERENCES

NQA-1 Subpart 2.14 Section 601 

NQA-1-2012 Subpart 3.1-2.1, Section 502 Graded Approach  

NQA-1-2012 SUBPART 2.22, Section 101 Definition of Graded Approach

DOE-HDBK-1230-2019 Section 6.5 Dedication Process

EPRI TR 3002002982 Section 5.7 Identify Acceptance Methods and Criteria

FAQ2
WHO DETERMINES REASONABLE ASSURANCE AND WHAT DOCUMENTATION IS REQUIRED?

ANSWER

Reasonable assurance is determined by the responsible engineering organization who originates the information used to develop the technical evaluation.  The dedicating entity verifies that the item/service meets the acceptance criteria and provides the documentation from one or more of the four acceptance methods to the responsible engineering organization to establish that reasonable assurance has been achieved such that the item/service will perform its intended safety function.  The documentation required to establish reasonable assurance is a complete technical evaluation along with the results and/or reports resulting from the use of one or more of the four acceptance methods.

AMPLIFYING INFORMATION

For the sake of clarity, the terms used in this answer are defined as follows:

  • Responsible Engineering Organization – the entity that develops the technical evaluation or provides the requisite information to a 3rd party dedicator that will be used in writing the technical evaluation (e.g. Pantex, SRNL).  CGD practitioners are typically delegated the authority to make the call on what constitute reasonable assurance but ultimately the responsibility lies with the engineering organization
  • Technical Evaluation – A documented evaluation that includes the safety function(s), like-for-like or equivalency determination, critical characteristics, acceptance criteria, and dedication methods.  (In the case of a build-to-print procurement, the dedication methods are typically determined by the Supplier.)
  • Dedicating Entity – As defined in NQA-1 Subpart 2.14 Section 601 (a).  This entity performs the verification activities, which may be the contractor (e.g. INL, Y-12), a Supplier, or a sub-supplier.

Factors that are considered in determining what constitutes reasonable assurance for a given situation are: safety function, whether that is an active or passive safety function, complexity of the item/service, the consequence of failure, the likelihood of failure, whether a replacement item is to be placed in a service requiring environmental or seismic qualification.

The responsible engineering organization obtains reasonable assurance from the dedication process by applying an appropriate level of rigor in the determination of critical characteristics, acceptance criteria, sampling plans and lot formation, and in choosing the method(s) of acceptance.

EPRI states “The decision that reasonable assurance has been attained is inherently subjective, and the judgment of reasonability may vary between different observers.”  These examples are one “observer’s” judgement call – each responsible engineering organization (the CGD practitioner) must make their own subjective, defendable call on what reasonable assurance is for each unique situation.

EXAMPLES

Example #1 – Item:  relay switch 

Safety Function:  start up emergency generator upon loss of commercial power within 60 seconds – active safety function.

Consequence of failure:  failure of the relay to start-up within 60 seconds would result in a possible release of radioactive contamination to the public

Likelihood of failure:  likelihood of failure is low as the original relay functioned for 40 years without fault.  Also, this is a relatively simple item with only one moving part

EQ/SQ:  this relay does not have any environmental qualification requirements, but it will be installed in a system that does require seismic qualification.

Given the conditions stated above, reasonable assurance would be attained via a combination of Method three and Method one.  Source surveillance would be conducted to witness the manufacturing of both a test relay and the relay to be put in service to verify that the relay’s materials and methods of fabrication are per the specification.  After receipt of the relays, the test relay will be tested to verify functionality and destructively tested to verify design limits and capabilities.  Additional critical characteristics must be verified to ensure that the new relay maintains the previously performed seismic qualification.  This is a moderately high level of rigor due to the high consequence and low likelihood of failure.

Example #2 – Item: lead 

Safety function: shield collocated workers from radiation exposure – passive safety function

Consequence of failure:  failure of the lead to provide required shielding would expose collocated workers to an unacceptable radiation dose.

Likelihood of failure:  likelihood of failure is low as shielding designs are analyzed for appropriate thickness with margin built in and the likelihood of a manufacturing failure that would result in an undetectable bubble in during the lead pour is also unlikely.

EQ/SQ:  not applicable as this is not a replacement item.

Given the conditions stated above, reasonable assurance would be attained via Method three source verification at the supplier’s facility to witness the dimensions of the forms into which the lead will be poured to ensure compliance with drawing dimensions and verify the final weight of the shield lead.  This is low level of rigor as the consequence of failure is low and the likelihood of failure is also low.

Example #3 – Item: structural fasteners in new construction

Safety Function: provide clamping force between two structural members of a nuclear facility – passive safety function

Consequence of failure:  failure of the fasteners would result in the breach of confinement boundary of nuclear material piping resulting in the exposure of collocated workers and even possibly the public

Likelihood of failure:  likelihood of failure is low as a large design margin is built in and there would have to be a concurrent or unnoticed successive failure of dozens of fasteners to cause a piping pressure boundary breach.

EQ/SQ:  not applicable as this is new construction

Given the conditions stated above, reasonable assurance would be attained through a CG survey of the supplier to verify that they have control of their manufacturing and testing processes such that the critical characteristics of fastener strength and fastener material chemistry are controlled.  This is a low level of rigor as the consequence of failure is moderately high, but the likelihood of failure is very low.

REFERENCES

ASME NQA-1 2017, Sub-part 2.14

EPRI Report NP-5652 on the Utilization of Commercial Grade Items. EPRI, Palo Alto, CA: 1994. TR-102260

DOE-HDBK-1230-2019, Commercial Grade Dedication Application Handbook

FAQ3
WHAT FACTORS SHOULD BE CONSIDERED IN DETERMINING THE DEGREE OF VERIFICATION?

ANSWER

The degree of verification for a given critical characteristic is inherently subjective and corresponds to the acceptance criteria to be met. The degree of verification may vary for the same item based on each end-use application. The goal is to provide a reasonable assurance based on engineering judgement.

AMPLIFYING INFORMATION

While there are many factors to be considered in determining degree of verification, a partial list might be:

  • Risk of the item failing 
  • Consequence of the item failing
  • Complexity of the item    
  • Tolerance of the specifications
  • The item’s stated safety function per safety basis document. 
  • Results of Technical evaluation, including the FMEA. 
  • The sample size of items chosen for acceptance

The word reasonable connotes a level of confidence that is justifiable but not absolute. In the context of product or service quality, reasonable assurance of performance must be based on facts, actions, or observations (objective evidence). Although these bases are objective and measurable, the inference of adequacy drawn from them—the decision that reasonable assurance has been attained—is inherently subjective, and the judgment of reasonability may vary between different observers. These judgments are commonly referred to as engineering judgment and should be documented. Reasonable assurance of the item’s ability to perform its intended safety function results from the combination of the technical evaluation and acceptance processes.  

EXAMPLES

Varying degree of verification based on stated safety function   

If procuring metal for the tank wall that holds a corrosive mixed waste, then require independent CMTR’s of material because the metallurgical properties are critical (e.g., corrosion resistance).   

If the same material holds makeup feed water, then only alloy analyzer verification simply to show an item is “stainless steel” might be adequate. 

 Varying degree of verification based on tolerance of the specifications with sample size

If the tolerance of a pipe is +-0.5 cm then sampling some fraction of a lot with a go-no-go gage might be sufficient.

If the tolerance of the same pipe is +-0.005 cm then sampling every item in a lot in multiple locations with a micrometer might be necessary.

REFERENCES 

10CFR50, Appendix B [7]

EPRI report TR-017218-R1, Guideline for Sampling in the Commercial-Grade Item Acceptance Process

FAQ4
WHEN APPLYING SAMPLING, HOW IS PRODUCTION TRACEABILITY ESTABLISHED?

ANSWER

Production traceability is established by sampling from lots that have traceability to a manufacturer’s heat number, production lot number, or batch number.  Further guidance for production traceability is in at EPRI NP-5652 TR-102260 2016 Appendix H.

AMPLIFYING INFORMATION

Production traceability can be established by several methods:

  1. If the manufacturer is on your QSL then a CofC incorporating production traceability would be acceptable.  
  2. If the manufacturer is not on your QSL then a CGD survey or source verification could be used to establish production traceability.  If you find issues than a change to sampling plan would be warranted.  
  3. No supplier visit, additional testing and documentation would be required to establish production traceability.  

EXAMPLES

A Widget is produced by a manufacturer in production lots which have a heat number.

The Company procures 10 Widgets. To establish production traceability the Company would include a clause about production traceability in the purchase order and verify with manufacturer or distributor their ability to conform to production traceability requirements which may include that all widgets bought on the purchase order come from the same heat number were possible. If not, sampling would then be applied to each heat number separately.

For example, a supplier might establish production traceability by performing overchecks on the chemical and physical properties of the CMTR for raw material received.  Then that supplier might apply their own marking/numbering to the tested lot of raw material that is traceable to the results of the test and the CMTR that are on file.  The supplier’s unique identification number is then used to maintain traceability between the material used in the as fabricated item back to the test results and CMTR.

REFERENCES

EPRI TR-017218-R1-1999

EPRI NP-5652 TR-102260 2016

EPRI NP-5652 TR-102260 2016 Appendix H

FAQ5
WHAT DOCUMENTS ESTABLISH THE SAFETY FUNCTIONS OF COMMERCIAL ITEMS OR SERVICES INTENDED FOR USE IN A NUCLEAR SAFETY APPLICATION?

ANSWER

Safety functions performed by the item or a host component in support of the overall safety function are described in the DSA for an existing facility, the PDSA for a facility under construction, or other safety basis documentation. A CGD is performed only on those items or services that perform a safety function. 

AMPLIFYING INFORMATION

Safety function – the performance of an item or service necessary to achieve safe, reliable, and effective utilization of nuclear energy and nuclear material processing. (DOE-HDBK-1230)

Safety basis – the documented safety analysis and hazard controls that provide reasonable assurance that a DOE nuclear facility can be operated safely in a manner that adequately protects workers, the public, and the environment.  (From 10CFR 830)

Hazard controls – measures to eliminate, limit, or mitigate hazards to workers, the public, or the environment, including

  1. Physical, design, structural, and engineering features;
  2. Safety structures, systems, and components;
  3. Safety management programs;
  4. Technical safety requirements; and
  5. Other controls necessary to provide adequate protection from hazards.  (From 10CFR 830)

All DOE-approved safety analyses (i.e., safety analysis reports/documented safety analyses), TSRs, USQs, hazard controls, and any Conditions of Approval within DOE safety evaluation reports that provide reasonable assurance that a DOE facility can be operated safely in a manner that adequately protects workers, the public, and the environment.

Under DOE regulatory requirements, there may be instances in which a commitment to implement ASME NQA-1 on a non-safety-related item such as hardware in support of compliance with air permit requirements would need the performance of a CGD. As such, critical characteristics would be those that support the performance of the item to meet program requirements and not the nuclear safety function. 

The question to the safety function should be raised to the responsible engineering and nuclear safety organizations.

EXAMPLES

Examples where upper tier design documents discuss safety classifications and safety functions can be found in:

  1. Preliminary Documented Safety Analysis (PDSA) – PDSA provides descriptions of safety class and safety significant SSCs, and functional requirements and performance criteria for early CGD development and to support procurement strategies. 
  2. Documented Safety Analysis (DSA) – Chapter 4 of the DSA describes the safety class and safety significant SSCs, their safety functions, and performance criteria. 
  3. Functional Classification – Provide system and component functional classification and system functional classification boundaries. Functional Classification Documents (or databases) can be effectively used to document evaluations on subcomponents of SSCs
  4. System Design Description (SDDs) – Convenient single point of reference that centralizes pertinent information or interpretations of details in supplier technical manuals and engineering documents

Examples of items and their safety functions:

  1. The safety function is often a subset of the item function.
  2. The function of an instrument may be to maintain the pressure boundary of a pipe system and provide a flow signal, but the safety function may only be to maintain the pressure boundary.
  3. For a computer program that tracks surveillances of safety SSCs to meet the technical safety requirements, the portion of the computer program that calculates dates based upon past surveillances completed and automatically notifies an engineer to schedule the surveillance would be the safety function, whereas the portion of that same computer program that stores the surveillance report may not be part of the safety function.

REFERENCES

DOE-STD-3024-2011, Content of System Design Descriptions

DOE-HDBK-1230-2019, Commercial Grade Dedication Application Handbook

ASME NQA-1 2017, Sub-part 2.14

FAQ6
IS AN ASSESSMENT BY A THIRD-PARTY CONFORMITY ASSESSMENT BODY, AN ACCEPTABLE ALTERNATIVE TO DIRECT EVALUATION OF A SUPPLIER?

ANSWER

Yes, use of an assessment performed by a third-party Conformity Assessment Body (CAB) can be an acceptable alternative to direct evaluation.  The degree to which the assessment is relied on should be consistent with the relative importance and scope of the item or activity being procured.

AMPLIFYING INFORMATION

DOE O 414.1D Attachment 1 Section 1 states “The contractor, using a graded approach, must develop a QAP and conduct work in accordance with the approved QAP that meets the requirements of this CRD.”  Hence, the site QAP must first make allowance for alternatives to direct evaluations and obtain buy-in from the regulator.

ASME NQA-1 Subpart 2.19 allows for the use of 3rd party accreditations of testing and calibration services if the accrediting body is an ILAC signatory and if the accreditation is to ISO-17025.  No such allowance is stated in NQA-1 for accreditation to ISO-17065 or others.

Accreditation refers to recognition given to an organization by an authoritative body. It is a process by which an authoritative body gives formal recognition that a CAB fulfills specified requirements and is competent to carry out specific tasks.

EXAMPLES

A testing laboratory, such as BACL, is requested to be added to a site’s QSL using the accreditation of a 3rd party such as A2LA instead of a direct evaluation at BACL’s facilities.  First, verify that the site QAP allows for such a qualification, then review the A2LA certificate to verify that the accreditation to ISO-17025 is current and that the scope of work is within the lab’s scope of accreditation.  This evaluation would need to be documented and the addition to the QSL would then proceed in accordance with the directions of the QAP.

An item is required to go through the commercial grade dedication process, and credit is intended to be given for a UL stamp to reduce the overall rigor of dedication. An item stamped with the UL certification mark demonstrates that the item meets the requirements of the certification scheme.  First, verify that the QAP allows for such credit, then verify that the product certification body has been accredited to ISO-17065 by an authoritative body such as A2LA.  Also, verify that the product is listed in the certification body’s directory of certified products and document the evaluation in accordance with the site QAP.

REFERENCES

ASME NQA-1 Subpart 2.19

DOE O 414.1D Attachment 1 CRD

https://www.iso.org/sites/cascoregulators/01_3_conformity-assessment-bodies.html

FAQ7
IS A CONSIDERATION OF CREDIBLE FAILURE MODES REQUIRED WHEN DESIGN CRITERIA IS AVAILABLE? IN THIS CASE, WHAT IS DESIGN CRITERIA?

ANSWER

When design criteria is available, consideration of credible failure modes and mechanisms is not required.  Design criteria is typically available to the dedicating entity when they have developed or acquired the design of the SSC.  The design criteria are the parameters and allowables specified in the design documents.

AMPLIFYING INFORMATION

A company that designs and manufactures an SSC would already have an in-depth knowledge of its strengths and weaknesses, and as such, they may not need to re-consider its potential failure modes when performing CGD.  On the other hand, a company that has acquired the SSC from the original designer/manufacturer would not have that inside knowledge and would therefore need to consider the credible failures in the CGD technical evaluation. 

Some SSC (e.g. an item that has an unusually high consequence of failure, one that is to be installed in an application other than that for which it was designed) might require even the original designer to re-evaluate the credible failures of the SSC in accordance with its end use.  In general, consideration of the credible failures, their likelihood, and the subsequent consequences of failure forms part of the foundation on which the procurement engineer chooses the appropriate critical characteristics and acceptance methods.

EXAMPLES

Jack’s Specialty Valves designs, manufactures, and provides ball valves to customers as a nuclear qualified item.  In performing CGD on these valves the supplier’s tech eval does not consider what the credible failure modes are of the valve as they have an inside knowledge of which characteristics are considered to be critical. 

If an assembly is determined to perform a safety function and had been designed by the dedicating entity, then the ASTM parameters of a certain component on the design drawing for the assembly might be used as the critical characteristics in the CGD plan. For example, the parameters found in ASTM A193 for a ½” grade B8M bolt could be used as critical characteristics.

REFERENCES

NQA-1 2008/2009a Section 401 fourth paragraph

The required ASTM standard edition must be included in the procurement documents, with which the supplier is bound to comply.  If the supplier utilizes a standard edition prior to that which is contractually required (e.g. 2000 in this example), then the design authority would need to evaluate the supplier’s proposed edition to ensure that it meets the same rigor as the approved edition.  If the proposed edition is not acceptable, then the required edition adherence would need to be communicated to the supplier, and may require a design change.

Generally, ASTM revisions do not routinely change specific requirements from one edition to the next.  Most edition changes involve combining standards or providing clarification associated with a previous edition, however this determination must be made on a case by case basis as described in the paragraph above.

Examples

A project underway at a DOE facility has specified that steel materials must meet the requirements of ASTM standards dated 2016 or newer.  A supplier plans on using material marked as compliant with the 2015 edition of ASTM A276/A276M, “Standard Specification for Stainless Steel Bars and Shapes” and submits an exception to the requirement to allow them to use their material with the justification that the revision from the 2015 edition of ASTM A276 to the most current edition has not changed any chemical constituent or mechanical property requirements.  The design authority would then need to determine what the differences are between the 2015 edition and any of the editions after 2016 (as the contract states) and to let the supplier know if their proposed edition is allowable.

References Engineering best practice

FAQ8
Can Commercial Grade Dedication be applied for items that don’t provide a nuclear safety function?

Answer

Although the process of Commercial Grade Dedication (CGD) can be applied to items not providing a nuclear safety function,  CGD is intended for items that perform safety functions and there may be little benefit in applying it otherwise.   For non-nuclear safety items with a greater degree of importance, use of the graded approach to quality in the procurement and acceptance processes allows a person to achieve similar results.

Amplifying Information

The process of Commercial Grade Dedication (CGD), as described in ASME NQA-1 Subpart 2.14, is specifically intended to allow the use of commercial grade items in a nuclear safety application.  If the item is not required to perform a nuclear safety function, then there is no requirement to implement the CGD process for that item. 

The dedication process can be time consuming and expensive, which must be considered in formulating the procurement strategy. Spending time and money to dedicate non-nuclear safety items can cause a significant negative impact on the schedules of nuclear safety activities.

ASME NQA-1 states that the requirements there-in are to be applied with a graded approach.  As such, consideration should be given to the item’s relative importance, such as to nuclear/radiological operations and safety, transportation safety, chemical safety, life safety, fire safety, or systems having a potential mission impact. If the item’s relative importance to the nuclear facility’s mission is significant (even though the item does not perform a nuclear safety function), then there may be value-added in performing an increased amount of CGD-like verification activities, as detailed in the acceptance and verification methods of ASME NQA-1, Requirement 7. If the item’s importance is minimal, then the value-added in an increased amount of CGD-like acceptance activities for the item is negligible.  To be clear, it is unnecessary to apply the CGD process (as described in NQA-1 Subpart 2.14) to obtain a greater degree of assurance that a non-nuclear safety item will perform as intended.

Examples

A 6-in diameter non-nuclear safety rupture disc that bursts at 49 psig @ 600 degrees F is to be utilized in a system, such as a shop air system with industrial safety requirements for protecting collocated workers.  In this case, including additional verification steps to ensure that the rupture disk will perform as expected would be warranted despite the additional cost/effort.  However, if the rupture disc is to be used in system such as a sanitary water line in which failure of the disk to rupture as expected does not place any person in danger or undue concern to facilities, then there is no value-added in spending the extra time or money on extra inspections or verification activities.

References

ASME NQA-1 Part 1 Introduction and Subpart 2.14

EPRI TR-3002002982

FAQ9
If a project’s design authority has determined that materials compliant with any ASTM after the year 2000 are acceptable, which ASTM year is appropriate to reference in the commercial grade dedication plan?

Answer

Referring to requirements for material compliant with any of the ASTM revisions after 2000 in the CGD plan is acceptable.  Early communication with engineering and any potential suppliers is key to ensuring that requirements are appropriately recorded and able to be complied with.

Amplifying Information

When deciding which ASTM standard edition to use in a CGD plan, consider the following:

  • Which edition(s) has engineering used in design?
  • What are the established codes of record?
  • If the facility has committed to more than one ASTM standard year, under what circumstances is the edition applied?
  • If the material is associated with a design change, what edition was used for the original design or previous design change(s)?

The required ASTM standard edition must be included in the procurement documents, with which the supplier is bound to comply.  If the supplier utilizes a standard edition prior to that which is contractually required (e.g. 2000 in this example), then the design authority would need to evaluate the supplier’s proposed edition to ensure that it meets the same rigor as the approved edition.  If the proposed edition is not acceptable, then the required edition adherence would need to be communicated to the supplier, and may require a design change.

Generally, ASTM revisions do not routinely change specific requirements from one edition to the next.  Most edition changes involve combining standards or providing clarification associated with a previous edition, however this determination must be made on a case by case basis as described in the paragraph above.

Examples

A project underway at a DOE facility has specified that steel materials must meet the requirements of ASTM standards dated 2016 or newer.  A supplier plans on using material marked as compliant with the 2015 edition of ASTM A276/A276M, “Standard Specification for Stainless Steel Bars and Shapes” and submits an exception to the requirement to allow them to use their material with the justification that the revision from the 2015 edition of ASTM A276 to the most current edition has not changed any chemical constituent or mechanical property requirements.  The design authority would then need to determine what the differences are between the 2015 edition and any of the editions after 2016 (as the contract states) and to let the supplier know if their proposed edition is allowable.

References Engineering best practice

FAQ10
How does the history of an item or supplier apply when choosing a sampling plan for special tests and inspections? 

Answer

An item’s performance history or a supplier’s acceptance history may be considered as one of the factors used in determining the level of rigor to be applied to the sampling plans used during the dedication process.

Amplifying Information

NQA-1 is mostly silent on the topic of using history in determining the correct sampling plan, however EPRI TR-017218 does address history in sample plan determination. In Section 2.4.2 of EPRI TR-017218 a list of selection factors for a given critical characteristic is provided, two of which are acceptance history of supplier’s products and item performance history.  An item’s or a supplier’s history are two qualitative inputs considered by the engineer in selecting an appropriate sampling plan.  

Examples

A DOE nuclear site has been purchasing HEPA filters for the last 8 years from the same manufacturer and dedicating them using Method 1 and a normal sampling plan for all the tests and inspections.  The procurement engineer reviewed the receiving reports and condition reports of any failures of the filters and notes that there have been more than one out of 10 filters that have had problems, of varying degrees.  Since the filters have passed receipt inspection but the problems have been consistently occurring, the procurement engineer decides to alter the CGD plan to require a tightened sampling plan for the required inspections and tests.

The construction of a DOE nuclear facility requires the procurement of many specialty pumps.  The CGD plan for these pumps included both Method 1 and 3.  The tests and inspections utilize both tightened and normal sampling plans as the manufacturer is new and the pumps have not been used previously in the application for which they have been designed.  The tests and inspections are rather onerous to perform so after the receipt and acceptance of a certain quantity of pumps the procurement engineer reviews the receipt inspection records and finds that all of the pumps to this point have passed the tests and inspections with only minor or no issues.  The CGD plan is then revised to change the sampling plan from tightened to normal on two of the tests and inspections due to an increased confidence in the supplier’s ability to control certain critical characteristics.

References

EPRI TR-017218-R1 Guideline for Sampling in the Commercial-Grade Item Acceptance Process

FAQ11
What is the difference between the use of history for selection of sampling plans and its use in a Method 4 dedication? 

Answer

Similar historical data may be used for both Method 4 dedication and in justifying the use of a certain sampling plan, the main difference is in how the data is documented.  Sampling plan historical information may only have to be referenced in the CGD plan, while the historical records/data used for Method 4 would require a documented analysis.

Amplifying Information

When determining the appropriate sampling plan for verification of a critical characteristic, there are many factors that should be considered.  Two of those factors are the acceptance history of a supplier’s products and the item’s performance history.  These same factors can also be used in verifying that certain critical characteristics meet the acceptance criteria through the implementation of Method 4. 

Documentation typical of sampling plans is a written justification of why the sample plan(s) was chosen, which might include acceptance and performance history of an item.  Any further requirements for what that documentation should include would be detailed in the site specific QAP.  Documentation requirements of Method 4 are very specific and prescriptive, that can include the analysis of the historical records and inclusion of those records or the results of the analysis in the CGD plan.  (For further information on this see FAQ “When using Method 4 as an acceptance method, what types of and how much documentation constitutes sufficient information?”)

Examples

If a DOE facility has been purchasing valves from the same supplier for the last 10 years and have been keeping track of both the acceptance history of that supplier and the performance history of that valve in service, then the CGD plan for that valve that might include sampling for their Method 1 tests and inspections might be able to reduce the sampling from normal to reduced due to such a positive acceptance and performance history. With those same historical records, the facility could also replace one or two of their Method 1 tests and inspections with a Method 4 acceptance method.  Either way, through maintaining a record of the acceptance and performance of the valve, the site would either be able to reduce the sampling rigor or implement Method 4 and reduce the overall effort expended on the dedication of the valves.

References

EPRI TR-017218-R1, Section 1.4.5

ASME NQA-1 Subpart 2.14 Section 605

EPRI TR-3002002982 Section 10

FAQ12
Method 4 seems to have been written for commercial nuclear power plants, can DOE facilities use Method 4 as an acceptance method?

Answer

Yes, DOE facility contractors and their qualified subcontractors can use Method 4 in their CGD plans.  The use of Method 4 at DOE sites would require that the Method 4 requirements be customized for the specific nuclear facility and discussed with and approved by the DOE oversight.

Amplifying Information

As the question points out, the four methods of acceptance were developed for commercial nuclear power plants.  There are no prohibitions against using Method 4 in CGD plans at DOE Nuclear facilities, in fact the DOE CGD handbook speaks at length on the subject. 

There are very few instances where any two facilities across the DOE complex are the same or even anywhere close to similar.  As such, the requirements found in ASME NQA-1 Subpart 2.14 and EPRI 3002002982 would most likely need to be tailored to apply to the facility at which Method 4 is intending to be used.  This tailoring might include clarification allowing the use of item and supplier records from the purchaser and their unique facility and not necessarily from other facilities across the DOE complex. 

Examples

A DOE national laboratory is wanting to take advantage of the many years of operational history of a specific valve at one of their nuclear facilities.  They will first review their QAP to ensure that Method 4 is an allowable method of dedication, if changes are required they will make those changes and receive approval from the local DOE oversight.  Dedication using Method 4 would then proceed following the approved process.

References

ASME NQA-1, Sub-part 2.14 Quality Assurance Requirements for Commercial Grade Items and Services

EPRI 3002002982, Section 10 METHOD 4: ITEM/SUPPLIER PERFORMANCE RECORD

DOE-HDBK-1230-2019, Section 6.5.5 Method 4 – Acceptable Supplier Item or Service Performance Record

FAQ13
When using Method 4 as an acceptance method, what types of and how much documentation constitutes sufficient information?

Answer

As with other methods of acceptance, the level of rigor or degree of confidence required from the historical performance records should be commensurate with the relative importance of the item or service’s nuclear safety function, including the consequence and likelihood of failure.

Amplifying Information

Documents required to show reasonable assurance are those that demonstrate the performance history from the successful utilization of other acceptance methods and/or pertinent industrywide performance data of an identical or equivalent item or service.  Historical performance records may include but are not limited to:

  • The monitored performance of an identical or equivalent item, which may include both records of failures, as well as records showing the lack of failures, while in service.   
  • Industry standard product tests, which can include records from the supplier of routine production tests or from samples sent to independent test laboratories.
  • Tests required by national codes and standards (not specific to the nuclear industry) governing the manufacturing or performance of the item, which can include supplier records of the manufacturing or performance tests, as required by applicable codes or standards.

Whereas one item may require an extensive collection of documentary evidence from the manufacturer, decades of performance history, and proof of compliance with industry code and standard required tests; a similar item under a different set of circumstances might only need documented evidence of not ever having failed in a way that would have compromised a given set of critical characteristics.

Examples

Bearings that are used in 3 similar nuclear safety pumps need periodic replacement according to the maintenance schedule.  There have been no recorded failures of any of the bearings while in service for the past 35 years.  The inspection and replacement records for the bearings in this application have been reviewed and a writeup has been included in the CGD plan to document the results of the review.  Because of the successful Method 4 historical records, a basic Method 1 receipt inspection will be utilized to check for part number, OD, and ID.  In this way reasonable assurance will have been achieved that the bearings will perform their nuclear safety function as required.

Nuclear instrument amplifier drawers (complex electrical items) are to be replaced and Method 4 is planning on being used along with Method 3 for the dedication of these items.  The replacement drawers are equivalent to the installed drawers, and there is a long operational history at the site in which they are installed of never failing in such a way that would compromise their ability to perform their nuclear safety function.  The manufacturer has made available the results of their routine in house product testing and the results of the code required tests that have been performed by 3rd party labs.  The operational history along with the test results from the supplier are to be analyzed and summarized in a report that is to be referenced in the CGD plan.  These historical performance records will allow for a reduced amount of rigor in the dedication plan, reducing the amount of time that the purchaser’s inspector will be required to be at the supplier’s facility and makes any further inspections or tests at or after receipt (Method 1) unnecessary. 

References

ASME NQA-1, Subpart 2.14 Quality Assurance Requirements for Commercial Grade Items and Services

DOE-HDBK-1230 Section 6.5.5 Method 4 – Acceptable Supplier Item or Service Performance Record

EPRI 3002002982 Section 10 METHOD 4: ITEM/SUPPLIER PERFORMANCE RECORD

FAQ14
Under what conditions is it acceptable to base the acceptance of an item or service solely on a signed Certificate of Conformance?

Answer

A certificate of conformance (C of C) may be used as the sole method of acceptance if the supplier has been evaluated and found to comply with the requirements for item acceptance found in the Purchaser’s QAP.  These C of C requirements are typically based on ASME NQA-1 Requirement 7 paragraph 503.

Amplifying Information

For procurement of an item or service from a nuclear qualified supplier:  A C of C may be used from a supplier that has been evaluated in accordance with the Purchaser’s QAP (these evaluation requirements are typically based on NQA-1 Requirement 7 Control of Purchased Items and Services para 200, Supplier Evaluation and Selection).

For procurement of an item or service from a commercial supplier: A C of C may be used when the responsible party has evaluated the supplier via a Method 2 Commercial Grade Survey and found an effectively implemented and documented quality program. Note that “the responsible party” may not be the same as the authority performing the acceptance (e.g. a lower tier supplier providing components to the direct sub-contractor). A DOE facility may delegate authority but may not delegate the final acceptance responsibility.

ASME NQA-1 Requirement 7 paragraph 503 Certificate of Conformance lists the requirements for when a C of C is used as the method of acceptance.  The PO should specifically call out these requirements with which the supplier must comply to take credit for the C of C upon receipt.

Examples

The Procurement Engineering Group had written a CGD plan for crucibles utilizing Method 2 Commercial Grade Survey (CGS) for acceptance. A CGS was successfully performed on an organization named MC. During this CGS the Critical Controls used to verify the Critical Characteristics of the crucibles were documented, approving the use of MC’s C of C. Production had run out of crucibles and was pushing hard for a re-supply to avoid a shut down. The procurement office received a 24-week lead time quote from MC but was able to secure a quote for crucibles from a new competitor (ACME) that met specification and could be delivered in 8 weeks. The buyer did not contact engineering and shortsightedly jumped on the offer of ACME crucibles. ACME delivered the specified crucibles 2 weeks early with a C of C providing compliance to all specifications. The C of C from ACME is not valid for acceptance because ACME had not undergone a proper Supplier Evaluation.

References

ASME NQA-1 Requirement 7

ASME NQA-1 Subpart 2.14

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