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NEI Presentation Operability Public Meeting August 30, 2018
	ML18241A369
Person / Time
Issue date:	08/30/2018
From:	Joseph Holonich; NRC/NRR/DLP/PLPB
To:	;
	Holonich J, NRR/DLP, 415-7297
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	Download: ML18241A369 (24)
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ENTRY CRITERIA FOR THE OPERABILITY DETERMINATION PROCESS NRC PUBLIC MEETING August 30, 2018

rights reserved.

Purpose

Describe the Entry Criteria for the Operability Determination Process

- Examples will be used for:

Illustrating each of the criteria Integrated examples to illustrate the entire process

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Background===

At a RUG III workshop held in May 2015, Operability Determination Process issues that were commonly encountered were discussed

Inconsistencies in Current Guidance

Inspection Manual (IMC) 0326 is not consistent in defining the conditions that warrant an Operability Determination

IMC-0326 uses the following terms to describe the conditions when an Operability Determination should be performed:

- Page 1- reasonably indicating a degraded or nonconforming condition

- Page 6 - Potential degraded/nonconforming conditions

- Pages 5 & 8 - Actual degraded/nonconforming conditions

- Page 6 - Presumption of operability has been lost

- Pages 5 & 8 - Operability called into question

Current Industry Situation

Typical site performs some type of Operability Assessment roughly two to ten times per day or more

- ODP entry occurs thousands of times per year

- Includes any assessment of an SSCs functional capability

Rarely, if ever, is a previously undetected inoperability uncovered

The proposed revision to the ODP entry criteria is intended to address this situation

Industry Solution

NEI process defines the entry criteria of the Operability Determination Process based on the Technical Specification definition of Operability

- Definition of Operable solely addresses functions

- Operability is the responsibility of the licensee

The Operability Process will be entered when all of the Three Required Criteria are satisfied

- SROs always will retain the option of requesting ODs

- All conditions continue to be assessed

Three Required Criteria

1. The deficient condition must affect a TS SSC installed in an operating unit.

A TS SSC is an SSC that has a functional impact on either:

o a specified safety function or o a required and necessary support function

2. The deficient condition must have a functional impact on the SSC. This includes the ability to perform required functions under postulated, off-normal design conditions.

3. The functional impact of the deficient condition must be substantive (i.e. non-trivial).

Substantive means:

o The functional impact is observable or o The deviation from as-designed values is more than 10%

First Criterion The deficient condition must affect a TS Comments/Details SSC installed in an operating unit. Includes the SSCs design, which will involve engineering. Practically, it is A TS SSC is an SSC that has a functional most commonly:

impact on either:

Calculations

a specified safety function or

Purchase and/or design specifications

a required and necessary support Documentation deficiencies that may function result in altered design requirements to possibly allow for either purchase of a different SSC or altered operation.

Examples That Would Not Satisfy the First Criterion

Vendor information associated with an SSC not installed

Design information errors with no potential for either altering a design specification or the SSCs operation

For example, drawing or database errors

Procedure formatting issues

An SSC with no relationship to any specified safety function or a required and necessary support function

Examples That Would Satisfy the First Criterion

Procedure issues that involve the execution of procedural steps, including procedural quality and/or completeness

An SSC with any relationship to any specified safety function or a required and necessary support function

A problem with a TS SSC has been discovered at a similar site within the nuclear industry. The problems presence has been confirmed on the unit.

Design information errors with a potential for either altering a design specification or the SSCs operation

Second Criterion The deficient condition must have a Comments/Details functional impact on the SSC. This includes If this Criterion is not satisfied, it the ability to perform required functions describes issues that provide no direct under postulated, off-normal design evidence regarding the functional conditions. status of an installed SSC.

No direct evidence is intended to mean:

There is no observable functional effect under any condition.

No evidence or indication that a functional impact would be manifest under off-normal/accident conditions.

Situations that could represent a problem indicate the need for further investigative work rather than an OD.

Examples That Would Not Satisfy the Second Criterion

The absence of an aspect of Quality Assurance does not mean that a functional problem is present. (Could versus Does)

Deficiencies in design of non-TS testing programs. (e.g.

Preventative testing program does not follow vendor recommendations.)

Deficient and/or missing radiographs of welds

Minor deficiencies in design documentation, including missing calculations.

No indication of functional issues associated with:

Non-safety-related SSCs (e.g.. Commercial grade gaskets) installed in safety-related applications

Issues initiated by the 10 CFR 21 process

Examples That Would Satisfy the Second Criterion

Design documentation deficiencies that result in altered requirements

Any indication of functional issues associated with:

Non-safety-related SSCs (e.g.. Commercial grade gaskets) installed in safety-related applications

Issues initiated by the 10 CFR 21 process with indication of functional issues

Procedure deficiencies that would prevent successful performance of a required TS function

Megger reading of a motor winding deviating from design values

Examples That Would Satisfy the Second Criterion

Missing washers and/or wrong size nuts on a pipe hanger

Corrosion on a structural steel member

An SSC has exhibited a reduction in reliability that exceeds the site-specific monitoring standards In every instance, the common thread is that the issue reflects some type of actual problem with an installed TS SSC.

Third Criterion The functional impact of the deficient Comments/Details condition must be substantive (i.e. non- This Criterion acknowledges that SSCs trivial). are designed, licensed, and installed

Substantive (more than trivial) means: with substantial margins. It includes consideration of design errors resulting

The functional impact is observable in functional impact.

or; If not satisfied, the issue would have the

The deviation from as-designed following characteristics:

values is more than 10%

The issue is manifest at functional level beneath that described in the UFSAR

There is no functional effect observable under any condition

No evidence or indication that a functional impact would be manifest under off-normal/accident conditions.

If the installed margin is amenable to an estimate, the margin loss is estimated to

Examples That Would Not Satisfy the Third Criterion

Megger reading of a motor winding deviating by less than 10%

from design

No unexplained motor symptoms

Non-compliance with a code of construction (excluding ASME code class 1) of less than 10%

Deviation from a parameter specified by the design, including EQ-related, by 10% or less

Calculation error with results deviating by 10% or less

For example, timing of safety injection timing did not properly account for loading of condensate pumps. Total condensate pump load is less than 10% of transformer design loading

Examples That Would Satisfy the Third Criterion

Cut electrical or instrument cable

Any indication of functional issues associated with:

Non-safety-related SSCs (e.g.. Commercial grade gaskets) installed in safety-related applications

Issues initiated by the 10 CFR 21 process

Missing or improper pipe hanger components with local indication of physical instability

Megger readings deviating from design values by more than 10%

Calculation error with results deviating by 10% or more

e.g. Timing of safety injection timing did not properly account for loading of condensate pumps Total condensate pump load is more than 10% of transformer design loading

Summary Flowchart The deficient condition must affect a TS SSC installed in an operating unit.

A TS SSC is an SSC that has a functional impact on either:

a specified safety function or;

a required and necessary support function The deficient condition must have a functional impact on the SSC. This includes the ability to perform required functions under postulated, off-normal design conditions.

The functional impact of the deficient condition must be substantive (i.e. non-trivial).

All Yes indicates that an Operability Any No indicates that an Operability Determination is Required Determination is Not Required

Illustration of Examples Non-safety related (NSR) Containment cooler fails Used to maintain containment pressure within specified limits

1 #2 #3 No N/A N/A NSR gasket installed in ECCS discharge piping discovered during an audit

1 #2 #3 Yes No N/A NSR gasket installed in ECCS discharge piping discovered following a plant walkdown identification of a leak

1 #2 #3 Yes Yes Yes

Illustration of Examples (cont.)

Vendor-recommended tests not performed on Safety-Related relays in an ECCS system

1 #2 #3 Yes No N/A Vendor-recommended tests on Safety-Related relays in an ECCS system has failed in an undetected manner in the past

1 #2 #3 Yes Yes Yes A steam trap that drains the steam supply to the turbine driven AFW pump governor is flooded

1 #2 #3 Yes Yes Yes

Illustration of Examples (cont.)

Important ECCS Operating Procedure steps are out of sequence

1 #2 #3 Yes Yes Yes ECCS Operating Procedure steps are vague and could allow improper operation

1 #2 #3 Yes No N/A Calculation error found resulting in a required ECCS pump flow increasing from 280 GPM to 290 GPM

1 #2 #3 Yes Yes No

Summary

The revised entry criteria (Three Required Criteria) provides a more consistent entry process linked to the Technical Specification definition of Operability

There is no change to the conduct of an ensuing Operability Determination due to the application of the Three Required Criteria

Look Ahead

The next meeting will focus on the NRC providing feedback on the Operability Determination Process Entry Criteria.

In a future meeting we will present the definition of Specified Safety Function (SSF)

- The Operability Determination Process is oriented around SSF

QUESTIONS / DISCUSSION

ML18241A369

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