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NRC Evaluation of NEI Recommendations 011426 (002)
	ML26015A096
Person / Time
Site:	Nuclear Energy Institute
Issue date:	01/14/2026
From:	Andy Campbell; Nuclear Energy Institute
To:	; NRC/NRR/DEX/ELTB
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EO 14300, Section 2 -

o Policy. It is the policy of the United States to:

(a) Reestablish the United States as the global leader in nuclear energy; (b) Facilitate increased deployment of new nuclear reactor technologies, such as Generation III+ and IV reactors, modular reactors, and microreactors, including by lowering regulatory and cost barriers to entry; (c) Facilitate the expansion of American nuclear energy capacity from approximately 100 GW in 2024 to 400 GW by 2050; (d) Employ emerging technologies to safely accelerate the modeling, simulation, testing, and approval of new reactor designs; (e) Support the continued operation of, and facilitate appropriate operational extensions for, the current nuclear fleet, as well as the reactivation of prematurely shuttered or partially completed nuclear facilities; and (f) Maintain the United States' leading reputation for nuclear safety [emphasis added]

EO 14300, Section 5 - The NRC shall issue final rules and guidance to conclude this revision process within 18 months of the date of this order.

In conducting this wholesale revision, the NRC shall be guided by the policies set forth in section 2 of this order and shall in particular:

(h) Adopt revised and, where feasible, determinate and data-backed thresholds to ensure that reactor safety assessments focus on credible, realistic risks. [emphasis added]

Industry Plans for Modernizations

Recent Actions o Revised NEIMA requirements o NRC staffing constraints o Wholesale revision

Maintain safety as the guiding principle for all activities

Role of regulator o Focus on activities that pose credible, realistic risk o Effective and efficient reviews, audits, and inspections

Long-term sustainability of regulatory infrastructure

Primarily focused on Part 50/52 license holders and applicants; however, most guidance is reactor technology agnostic

Acknowledge changes since the inception of the CCF policy o Technology improvements o Process improvements o Standards improvements

Use data to inform decisions o EPRI research findings

Incremental changes have not reduced regulatory barriers o Response to Executive Order needs to be a foundational change

Most recent License Amendment Request (LAR) review > 3 years o No safety significant issues identified that required design changes

Process changes are not resulting in efficiency benefits for large modifications

Digital Common Cause Failure (CCF) continues to pose significant regulatory burden despite no regulatory requirement nor data to support its credibility

May 2019 Commission Briefing1 - EPRI Presentation:

o Recent research using field failure data revealed no platform level Software Common Cause Failures (SCCF) over approx. 2 billion hours of operation for IEC-61508 SIL certified PLCs o SCCFs are no more problematic than other CCF contributors o No identified events where diverse platforms would have been effective in protecting against SCCF o Several events confirmed effectiveness of signal and functional diversity in protecting against SCCF 1https://www.nrc.gov/reading-rm/doc-collections/commission/slides/2019/20190514/index

SECY-91-292 identifies digital I&C issues such as:

o Lack of experience in nuclear applications o Absence of requirements and standards related to digital-specific design aspects o Lack of guidance and standards related to software development processes

SECY-93-087 o Quality and diversity should be used to address CCF o Policy relies on diversity due to the lack of robust quality standards and operating experience

SRM-SECY-93-087 establishes Digital I&C (DI&C) Common Cause Failure (CCF) as a Beyond Design Basis Event (BDBE) o The staff's position has been modified in essentially two respects: First, inasmuch as common mode failures are beyond design-basis events, the analysis of such events should be on a best-estimate basis

SECY-22-0076 o Does not fundamentally update the policy to reflect the changes to DI&C quality processes, standards, technology changes, or operating experience

SRM-SECY-22-0076 maintains SR DI&C CCF as a BDBE

BTP-7-19, Rev. 9 states:

o the NRC staff considers CCFs in DI&C systems to be beyond design-basis events.

©2026 Nuclear Energy Institute 12 Activity Screened In Previously Evaluated Not Previously Evaluated Accidents SSC Malfunctions Frequency Likelihood Accident Different Type SSC Malfunction Diff. Result Criterion 1 Criterion 2 Create a Possibility Criterion 5 Criterion 6

Criterion 1 and 5 -

Accidents (Frequency and Type)

Criterion 2 and 6 -

SSC Malfunctions (Likelihood and Diff.

Result) 10 CFR 50.59

The term 'accidents' refers to the anticipated (or abnormal) operational transients and postulated design basis accidents... (NEI 96-07, Section 3.2)

Therefore, for purposes of 10 CFR 50.59, both Anticipated Operational Occurrences (AOOs) and Postulated Accidents (PAs) fall within the definition of accident. (NEI 96-07 Appendix D, Section 4.3.1)

NEI 96-07, Section 4.3.5 o The set of accidents that a facility must postulate for purposes of UFSAR safety analyses [] are often referred to as design basis accidents [emphasis added]

o The possible accidents of a different type are limited to those that are as likely to happen as those previously evaluated in the UFSAR. The accident must be credible in the sense of having been created within the range of assumptions

[emphasis added]

NEI 96-07 Section 4.3.2 o The determination of whether the likelihood of malfunction is more than minimally increase is made at a level consistent with existing UFSAR-described failure modes and effects analyses. [emphasis added]

NEI 96-07 Section 4.3.2 and 4.3.6 o [] a proposed activity that introduces a cross-tie or credible common mode failure (e.g., as a result of an analog to digital upgrade) should be evaluated further...

[emphasis added]

The likelihood of CCF is sufficiently low when the following are applied:

Design Attributes

i. Robust design and analysis processes (e.g., EPRI Digital Engineering Guide Framework) ii. Application of industry standards (e.g., IEEE 603, IEEE 7-4.3.2, etc.)

Quality products and system development processes (e.g., Appendix B and/or IEC 61508 Safety Integrity Level certification)

Operational Experience (e.g., EPRI research findings)

The likelihood of CCF is SR digital SSCs is driven below the level of credible, realistic risk (NEI recommends 1 x 10-4 consistent with BDBE range in License Modernization Project guidance)

10 CFR 50.59 should remain a viable pathway for ALL plant changes that can demonstrate sufficiently low likelihood of CCF

LAR submittals should be considered for activities that reduce redundancy, diversity, separation or independence of the design function(s) beyond the level credited in the UFSAR

LAR submittals should be focused on specific criteria that require prior NRC approval, not comprehensive reviews

Accelerating NRC Reform recommendations intended to present a foundational change acknowledging the progress since 1991 policy o Identifies impacts to policy, staff guidance and industry guidance intended to allow ALL modifications to be screened/evaluated in 10 CFR 50.59

NEI 20-07, Guidance for Addressing Common Cause Failure in High Safety-Significant Safety-Related Digital I&C Systems o On Hold - Will still hold regulatory value and plan to re-purpose based on Action Plan

NEI 25-09, Guidance for Developing a Digital I&C Licensing Strategy o Guidance for interdependence, equipment qualification and human factors o Guidance for evaluating reductions to redundancy, diversity, separation or independence of the design function(s) beyond the level credited in the UFSAR

I&C Documents (https://www.nrc.gov/reactors/digital/refguide) o 7 Regulations o 22 General Design Criteria o NUREG-0800, Chapter 7 (537 pages) o 2 Open Interim Staff Guidance o 28 Regulatory Guides (updated to include RG 1.250)

Human Factors Engineering Documents o 1 Regulation o NUREG-0800, Chapter 18 o 5 other NUREG documents

Opportunities to meet current and future industry needs:

o Remove unnecessary duplication of regulatory requirements o Allow use of modern standards that reflect state of practice o More efficient guidance to improve efficiency, predictability, and timeliness

Industry recommendations:

o Do not result in a reduction of reasonable assurance of adequate protection o Improves efficiency for licensing and adoption of future standards

Eliminate 10 CFR 50.55a(h)

Update RG 1.153 to endorse standards (e.g., IEEE 279, IEEE 603) to meet 10 CFR 50, Appendix A General Design Criteria (or Principal Design Criteria for Advanced Reactors)

Benefits:

o Remove duplicative requirements o Reduced burden to use alternative or exemption o More timely and efficient update process (i.e., would not require rulemaking)

Industry strongly opposed to current proposed rulemaking which expands the scope of regulation to include CCF requirements o Defer to future public meeting on proposed rulemaking for details

NUREG-0800 Chapter 7, Appendix 7.1-A provides staff acceptance criteria and guidelines for I&C systems important to safety.

o Directs staff to use IBRed standard as acceptance criteria for demonstrating compliance with GDC

Requirements in IBRed standards are addressed by GDC GDC IEEE 279-1971 Section IEEE 603 Section(s) 1 4.3 5.3 2

3 4

4 4.4 5.4 13 4.9, 4.13, 4.17, 4.19 5.8, 6.2, 6.5, 7.2 20 3, 4.1, 4.5, 4.15 4, 5, 5.5, 6.1, 6.8, 7.1 21 3, 4.1-3, 4.5-19, 4.21, 4.22 4, 5.1-3, 5.5-15, 6.2-8, 7.2-5, 8 22 3, 4.2-7, 4.15, 4.17 4, 5.1, 5.3-6, 6.2, 6.3, 6.8, 7.2, 8 23 4.5 5.5 24 4.2, 4.5-7 5.1, 5.6, 5.12, 6.3, 6.6, 8

25 3

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©2026 Nuclear Energy Institute 23 Unnecessary Duplication 10 CFR 50.34(f)(2)(v) 10 CFR 50.55a(h) IBRed Standards Provide for automatic indication of the bypassed and operable status of safety systems. (I.D.3)

IEEE 279-1971 4.13 Indication of Bypasses. If the protective action of some part of the system has been bypassed or deliberately rendered inoperative for any purpose, this fact shall be continuously indicated in the control room.

IEEE 603-1991 5.8.3 Indication of Bypasses. If the protective actions of some part of a safety system have been bypassed or deliberately rendered inoperative for any purpose other than an operating bypass, continued indication of this fact for each affected safety group shall be provided in the control room.

5.8.3.1 This display instrumentation need not be part of the safety systems.

5.8.3.2 This indication shall be automatically actuated if the bypass or inoperative condition (a) is expected to occur more frequently than once a year, and (b) is expected to occur when the affected system is required to be operable.

5.8.3.3 The capability shall exist in the control room to manually activate this display indication.

NEIs ADVANCE Act recommendations intended to:

o Update outdated regulatory infrastructure documents (e.g., Regulatory Guides) o Evaluate modern processes (e.g., systems engineering approaches) o Consolidate staff and industry guidance for ease of use and maintenance

Digital I&C has not been treated commensurate with other Executive Order priorities o Subsequent License Renewal Safety & Environmental Reviews reduced review hours 70% since 2019 (26,000 hrs 7,000 hrs) o Reactor Oversight Program

~15% baseline inspection scope reduction by going to minimum sample sizes Reduced size & scope of comprehensive engineering team inspection (CETI)

Regulatory burden associated with Digital I&C is impeding industry from pursuing digital upgrades that enhance safety and plant reliability o Digital upgrades address equipment obsolescence, improve equipment monitoring, expands automation capabilities o Incentivize plants to pursue digital upgrades, do not continue with established barriers Industry expects implementation of actions to remove digital I&C burden as part of Executive Order 14300 response (i.e., implemented no later that 11/23/26)

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