United States Nuclear Regulatory Commission - Protecting People and the Environment

ROP Framework

icon/hyperlink for Framework of the ROP page consisting of a magenta-colored circle with light green outline and in the center a white outline of 6 rectangular boxes joined togetherThe following information describes the framework of the Reactor Oversight Process (ROP).


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Regulatory Framework

The U.S. Nuclear Regulatory Commission's (NRC's) regulatory framework for reactor oversight is a risk-informed, tiered approach to ensuring plant safety. There are three key strategic performance areas: reactor safety, radiation safety, and safeguards. Within each strategic performance area are cornerstones that reflect the essential safety aspects of facility operation.

Within this framework, the NRC's ROP provides a means to collect information about licensee performance, assess the information for its safety significance, and provide for appropriate licensee and NRC response.

Regulatory Oversight Framework image consisting of the words Reactor Oversight Framework in black color on white background with a flowchart type presentation consisting of various sized and colored rectangles showing each component of the ROP Framework - Mission: Protect Public Health and Safety in the Use of Nuclear Power; Strategic Performance Areas: with a green background rectangle and the words Reactor Safety; an orange rectangle with the words Radiation Safety, and a Patina colored rectangle with the words Safeguards; Cornerstones: with green rectangles for Initiating Events, Mitigating Systems, Barrier Integrity, Emergency Preparedness; orange rectangles with Public Radiation and Occupational Radiation, and a Patina colored rectangle with Security; Cross-Cutting Areas: Pale Fuchsia color rectangles with Human Performance, Problem Indentification and Resolution, and Safety-Conscious Work Environment

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Cornerstones of Safe Operation

The ROP is anchored in the NRC's mission to ensure public health and safety in the operation of commercial power plants. That will always remain the agency's overarching responsibility.

The objective is to monitor performance in three broad areas:

(1) reactor safety (avoiding accidents and reducing the consequences of accidents if they occur)
(2) radiation safety for both plant workers and the public during routine operations
(3) protection of the plant against sabotage or other security threats

To measure plant performance, the oversight program focuses on seven specific "cornerstones", which support the safety of plant operations in the three broad strategic areas.  See the Inspection Manual by Cornerstone page for more information.

In addition to the cornerstones, the ROP features three "cross-cutting" elements, so named because they affect and are therefore part of each of the cornerstones:

Human Performance: This element monitors the licensee's decisionmaking process, availability and adequacy of resources to ensure nuclear safety, coordination of work activities, and personnel work practices.

Problem Identification and Resolution: This element monitors the licensee's corrective action and operating experience programs, and the licensee's self- and independent- assessments.

Safety-Conscious Work Environment: This element monitors an environment in which workers feel free to raise nuclear safety concerns without fear of harassment, intimidation, retaliation, or discrimination.

The review and assessment of these cross-cutting elements have an important role in the new program.

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Overall Description

The figure below gives an overview of the ROP. For each cornerstone, the NRC develops findings from inspections, and licensees collect performance indicator data. The NRC evaluates inspection findings for safety significance using a significance determination process and compares performance indicators against prescribed risk-informed thresholds. The agency then assesses the resulting information and determines an appropriate response using the guidelines in an action matrix. Response can include supplemental inspections for selected issues or enforcement actions on significant inspection findings. The NRC communicates the results of its performance assessment and its inspection plans and other planned actions in publicly available correspondence, on the NRC Web site, and through public meetings with each licensee.

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Measuring and Inspecting Nuclear Plant Performance

The NRC measures nuclear plant performance by monitoring objective performance indicators and by conducting the NRC inspection program. Monitoring and inspection closely focus on those plant activities having the greatest impact on safety and overall risk. In addition, the NRC conducts both periodic and annual reviews of the effectiveness of each utility's programs to identify and correct problems.

Performance indicators use objective data to monitor performance within each of the "cornerstone" areas. The utilities generate the data that make up the performance indicators and submit these data to the NRC quarterly. Each performance indicator is measured against established thresholds which are related to their effect on safety.

While performance indicators can provide insights into plant performance in selected areas, the NRC's inspection program provides a greater depth and breadth of information for monitoring and assessing plant performance.  The inspection program is designed to verify the accuracy of performance indicator information and to assess performance that is not directly measured by the performance indicator data.

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Using Performance Indicators

Evaluation of Performance Indicator Data

Each plant operator reports performance indicators to the NRC quarterly. Following compilation and review by NRC staff, the NRC posts performance indicators on the NRC Web site. NRC staff evaluates performance indicator data and integrates the data with inspection findings to develop an assessment of licensee performance. Each performance indicator is measured against the criteria using a color-coded system for safety performance:

Green indicates performance within an expected performance level where the associated cornerstone objectives are met.

White represents performance outside an expected range of nominal utility performance but related cornerstone objectives are still being met.

Yellow indicates related cornerstone objectives are being met, but with a minimal reduction in the safety margin.

Red signals a significant reduction in safety margin in the area measured by the performance indicator. The NRC staff evaluates and integrates the performance indicator data with findings of the NRC inspection program to provide a broad assessment of the plant's safety performance.

The staff uses the significance determination process to determine the safety or security significance of inspection findings. This process provides an initial screening to identify those inspection findings that do not result in a significant increase in plant risk (a "green" finding).

Green indicates a finding of very low safety or security significance.

White indicates a finding of low to moderate safety or security significance.

Yellow indicates a finding of substantial safety or security significance.

Red indicates a finding of high safety or security significance.

Reactor Oversight Action Matrix Performance Indicators image consisting of the words Reactor Oversight Action Matrix Performance Indicators main title; Performance Indicators subtitle with green, white, yellow and red catetories; Inspection Findings subtitle also with green, white, yellow and red catetories; both also have a right pointing arrow with the words Increasing Safety Significance

Performance Indicators by Cornerstone

Performance indicators are reported quarterly by operators of nuclear plants, reviewed by the NRC staff, and posted on the NRC's Web site.
Safety Cornerstone Performance Indicator
Initiating Events Unplanned Scrams (Automatic and Manual Reactor Shutdowns) per 7,000 Critical Hours (IE01)
Unplanned Power Changes per 7,000 Critical Hours (IE03)
Unplanned Scrams with Complications (IE04)
Mitigating Systems Safety System Functional Failures (MS05)
Emergency AC Power Systems (MS06)
High Pressure Injection Systems (MS07)
Heat Removal Systems (MS08)
Residual Heat Removal Systems (MS09)
Cooling Water Systems (MS10)
Barrier Integrity Reactor Coolant System Specific Activity (BI01)
Reactor Cooling System Leakage (BI02)
Emergency Preparedness Drill/Exercise Performance (EP01)
Emergency Response Organization Drill Participation (EP02)
Alert and Notification System Reliability (EP03)
Public Radiation Safety RETS/OCDM Radiological Effluent Occurrence (PR01)
Occupational Radiation Safety Occupational Exposure Control Effectiveness (OR01)
Security Not Publicly Available*

* The security cornerstone is an important component of the ROP, which includes various security inspection activities the NRC uses to verify licensee compliance with Commission regulations and thus ensure public health and safety. The Commission determined in the staff requirements memorandum (SRM) for SECY-04-0191, "Withholding Sensitive Unclassified Information Concerning Nuclear Power Reactors from Public Disclosure," dated November 9, 2004, that specific information related to findings and performance indicators associated with the security cornerstone will not be publicly available to ensure that security-related information is not provided to a possible adversary. Security inspection report cover letters will be available on the NRC Web site; however, security-related information on the details of inspection finding(s) will not be displayed.

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Inspection Programs

The revised oversight program continues to use a variety of NRC inspectors who monitor plant activities. The program includes baseline inspections common to all nuclear plants. The baseline inspection program, based on the cornerstone areas, focuses on activities and systems that are "risk significant" (in other words, those activities and systems that have a potential to trigger an accident, can mitigate the effects of an accident, or can increase the consequences of a possible accident). The inspection program will also review the cross-cutting issues of human performance, the safety-conscious work environment, and how the utilities find and fix problems. The NRC will perform inspections beyond the baseline at plants with performance below established thresholds, as assessed through information gained from performance indicators and NRC inspections. The NRC may also perform additional inspections in response to a specific event or problem that may arise at a plant.

NRC resident inspectors stationed at each nuclear power plant and inspectors based in one of the four NRC regional offices or in NRC Headquarters in Rockville, MD, will perform the inspections. The regional offices are in King of Prussia, PA; Atlanta, GA; Lisle, IL; and Arlington, TX.

For the new inspection program, the NRC used a risk-informed approach to select areas to inspect within each cornerstone. The agency chose the inspection areas based on their importance from the point of view of potential risk, past operational experience, and regulatory requirements.

The baseline inspection program has three parts:

(1) inspections of areas not covered by performance indicators or where a performance indicator does not fully cover the inspection area
(2) inspections to verify the accuracy of a licensee's reports on performance indicators
(3) thorough reviews of the utility's effectiveness in independently finding and resolving problems

The NRC will issue inspection reports for all inspections just as under the previous inspection program. The agency will make these reports available to the public on the NRC Web site and in the Public Document Room at NRC Headquarters.

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Assessing Plant Performance

The inspection staff has developed a procedure called the "significance determination process" to help inspectors determine the safety significance of inspection findings. The staff will use the process for an initial screening review to identify those inspection findings that would not significantly increase risk and thus need not be analyzed further (i.e., a "green finding"). Remaining inspection findings, which may affect plant risk, will then be subject to a more thorough risk assessment, using the next phase of the significance determination process. This more detailed assessment may involve NRC risk experts from the appropriate regional office and further review by the utility's plant staff. To determine appropriate further action, the NRC will use the final outcome of the review, evaluating whether the finding is green, white, yellow, or red.

Each calendar quarter (every 3 months), the resident inspectors and the inspection staff in the regional office will review the performance of all nuclear power plants in that region as measured by the performance indicators and by inspection findings. Every 6 months, the NRC staff will expand the review to include planning of inspections for the following 12-month period.

Each year, the final quarterly review will involve a more detailed assessment of plant performance over the previous 12 months and preparation of a performance report, as well as the inspection plan for the following year. This review will include NRC Headquarters staff members, the regional staff, and the resident inspectors.

The NRC will make these annual performance reports available to the public on the NRC Web site. The NRC staff will also hold public meetings at each plant to discuss the plant's previous year's performance.

In addition, NRC senior management will review the adequacy of agency actions for plants with significant performance problems. The managers will also take a wider view of both the overall industry performance and the performance of the agency's regulatory programs. The performance of plants requiring heightened agency scrutiny will then be discussed during a public meeting with the NRC Commissioners at the agency's headquarters in Rockville, MD.

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NRC Response to Plant Performance

The NRC's quarterly reviews of plant performance, which consider both performance indicators and inspection findings, will determine what additional actions, if any, the NRC will take if there are signs of declining performance. Under the revised ROP, the NRC's quarterly review more strongly links regulatory actions to performance criteria. The agency believes this creates a more predictable approach to enforcement. The process uses five levels of regulatory response with NRC regulatory review increasing as plant performance declines. The appropriate regional office manages the first two levels of heightened regulatory review. The last two levels call for an agency response, involving senior management attention from both headquarters and regional offices.

The oversight program uses the same tools that the NRC has traditionally used when dealing with declining plant performance and violations. However, the NRC now uses these tools in a more predictable manner that is commensurate with the decreased safety performance. In the past, the NRC tended to use fines as a prime indicator of agency concern and as a motivator for licensee corrective actions. Under the new approach, there is a system of specified agency actions if performance declines. The NRC will now generally reserve fines for such things as discriminating against workers raising safety concerns or for willfully misreporting required information.

The NRC's actions for performance below the "green" level may include meetings with the utility, additional inspections, and required reviews and response by the utility. Further declines in performance would warrant stronger action by the NRC, including a civil order or even the suspension of the utility's operating license.

NRC response plan to ROP assessment of plant performance - a graphical representation of the new process which utilizes five levels of regulatory response with NRC regulatory review increasing as plant performance declines; consists of two columns: ROP Action Mtrix Assessment of Plant Performance, and NRC Response (bullet items); The first two levels of heightened regulatory review are managed by the appropriate regional office. The last two levels call for an agency response, involving senior management attention from both headquarters and regional offices;

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Violations of NRC Requirements

For each violation of regulations found during NRC inspections, the staff will evaluate the violation to determine its effect on plant safety and risk. If the violation is of very low safety significance, the staff will discuss the violation in an inspection report and take no formal enforcement action. In such cases, the NRC expects the utility to deal with the violation through its corrective action program by correcting the violation and taking steps to prevent a recurrence. The staff may also review the issue during future NRC inspections.

If the NRC risk evaluation finds that the violation has higher safety significance, the NRC will issue a notice of violation. The agency may also issue a notice of violation if the utility fails to correct a violation of low safety significance in a reasonable period of time or if the agency finds the violation to be willful.

The notice of violation requires the utility to respond formally to the NRC with planned actions to correct the violation and steps for preventing the violation from occurring again. The agency will then review the utility's actions in a later inspection.

Normally, these violations will not be subject to a fine. However, some violations may warrant a fine because of their unusual significance. Possible examples include exceeding a safety limit specified in a reactor license or the inadvertent startup of a reactor.

In addition, some violations will call for the traditional enforcement approach, including the possible issuance of fines. Examples of such violations include the following:

  • discrimination against workers for raising safety issues or other willful violations

  • actions that may adversely affect the NRC's ability to monitor utility activities, including failure to report required information, failure to obtain NRC approval for plant changes, failure to maintain accurate records, or failure to provide the NRC with complete and accurate information

  • incidents with actual safety consequences, including radiation exposures above NRC limits, releases of radioactive material above NRC limits, or failure to notify government agencies when emergency response is required

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Communications and Making Information Available to the Public

The revised ROP will provide more information on plant performance than in the past, and the information will be available more frequently. The information will be available to the public on the NRC Web site and in the Public Document Room at NRC Headquarters.

A utility will submit to the NRC the quarterly performance indicator data for each nuclear power plant it operates. The NRC staff will review the data for completeness and accuracy. The staff will also evaluate inspection findings for that quarter to determine their safety significance. This review uses the agency's significance determination process, which is keyed to how plant safety systems and procedures contribute to the risk of a potential accident.

The NRC will place the performance indicators and the assessment of inspection findings on its Web site using the color notation of their significance (green, white, yellow, or red). The statistics and inspection findings underlying the color notation will also be posted on the NRC Web site.

The revised oversight program is intended to fulfill the following four goals established by the Commission:

(1) Maintain safety by establishing a regulatory oversight framework that provides assurance that plants continue to be operated safely by plant operators. Maintaining safety is the NRC's overarching mission.
(2) Enhance public confidence in the NRC's regulatory program by increasing the predictability, consistency, objectivity and transparency of the oversight process so that all parties will be well served by the changes taking place.
(3) Improve the effectiveness, efficiency, and realism of the oversight process by focusing both agency resources and utility resources on those issues with the most safety-significance.
(4) Reduce unnecessary regulatory burden by using a more efficient and effective process.

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Comparison with the Previous Program

The previous ROP evolved over a period of time when the nuclear power industry was less mature and there was much less operational experience on which to base rules and regulations. Very conservative judgments governed the rules and regulations. Because significant plant operating events occurred, the oversight process tended to be reactive and prescriptive, closely observing plant performance for adherence to the regulations and responding to operational problems as they occurred.

The nuclear industry now has the benefit of four decades of operational experience, and, in general, plant performance has improved steadily, particularly over the last decade or so. The new ROP focuses more of the agency's resources on the relatively small number of plants that evidence performance problems. The baseline inspection program is considered the minimum inspection effort needed to ensure that plants meet the "safety cornerstone" objectives. NRC resident inspectors and inspectors from the regional offices conduct the baseline inspection program at all reactor sites.

Plants that do not meet the safety cornerstone objectives (as measured by performance indicators and inspection findings) will receive increased inspection focusing on areas of declining performance. The NRC will also conduct inspections beyond the baseline program, even at plants performing well, if there are operational problems or events the agency believes require greater scrutiny. Generic problems, affecting some or all plants, may also require additional inspections.

The previous oversight program relied more heavily on fines when violations occurred, while the new program will make broader use of other enforcement tools such as orders and other formal regulatory actions. Under the previous program, the NRC often issued fines long after the violations occurred and the amounts of the fines were substantially less than the cost of repairs or the costs associated with a shutdown to correct the violations. The new process is intended to be more effective in correcting performance or equipment problems because the agency's response will be both timelier and more predictable.

The new assessment program is substantially different from the previous process. It makes greater use of objective performance indicators. Together, the indicators and inspection findings provide the information needed to support quarterly reviews of plant performance, with the results posted on the NRC's Web site.

The new assessment process also features expanded semiannual reviews, including inspection planning and a performance report, all of which will also be posted on the NRC Web site.

The performance assessment process previously involved three processes:

Plant Performance Review: Every 6 months, the NRC assessed events, inspection findings, and other data. The agency used this review to plan future inspections and to identify those plants with declining performance that required further NRC action.

Senior Management Meetings: Twice a year, NRC senior managers assessed plant performance to discuss regulatory action needed at plants with declining performance. The managers designated those plants warranting heightened NRC monitoring as being on a watch list. These watch list plants were then discussed at a public meeting with the Commission.

Systematic Assessment of Licensee Performance: Every 12–24 months, the NRC staff performed a separate review of the performance of each plant, preparing a report on the systematic assessment of licensee performance. This report included a numerical rating of the plant in four categories (plant operations, maintenance, engineering, and plant support), as well as a narrative discussion of performance in each area.

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Page Last Reviewed/Updated Friday, April 20, 2018