Reactor Oversight 

Process

Photo courtesy of Florida Power & Light Company
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R E A C T O R O V E R S I G H T P R O C E S S 

CONTENTS

1 INTRODUCTION

1 REACTOR OVERSIGHT PROCESS

2 REACTOR OVERSIGHT PROCESS CORNERSTONES

3 CROSS-CUTTING AREAS

4 MEASURING AND INSPECTING NUCLEAR PLANT PERFORMANCE

6 ASSESSMENT OF PLANT PERFORMANCE

7 NRC RESPONSE TO PLANT PERFORMANCE

8 VIOLATIONS OF NRC REQUIREMENTS

8 PERFORMANCE INFORMATION AVAILABLE TO THE PUBLIC

10 GLOSSARY
United States Nuclear Regulatory Commission
R E A C T O R O V E R S I G H T P R O C E S S 

1

INTRODUCTION

The mission of the U.S. Nuclear Regulatory 

Commission (NRC) is to license and regulate 

the Nation’s civilian use of radioactive 

materials to protect public health and 

safety, promote the common defense and 

security, and protect the environment. The 

agency regulates commercial nuclear power 

plants and other uses of nuclear materials, 

such as in nuclear medicine, through 

licensing, inspection, and enforcement of its 

requirements. 

The agency does not operate the plants. 

Rather it establishes requirements for the 

design, construction, operation, and security 

of commercial nuclear power plants in the 

United States. The agency ensures the plants 

are operated safely and securely within these 

requirements by licensing the plants to operate, 

licensing control room personnel, establishing 

technical specifications for operating each 

plant, and inspecting plants on a daily basis.

The NRC uses the Reactor Oversight Process 

(ROP) to verify that U.S. reactors are operating 

in accordance with NRC rules, regulations, 

and license requirements. If they are not, 

the NRC can provide additional inspections 

and other actions in order to protect public 

health and the environment. The ROP benefits 

from what the NRC has learned from 30 

years of improvements in nuclear industry 

performance, as well as improved approaches 

to inspecting and evaluating the safety and 

security performance of NRC-licensed plants.

Additional information about the NRC is available 

on its Web site: http://www.nrc.gov

REACTOR OVERSIGHT PROCESS

The ROP is the agency’s program to inspect, 

measure, and assess the safety and security 

performance of operating commercial nuclear 

power plants, and to respond to any decline 

in their performance. The program was 

implemented in 2000, with the goal of providing 

an objective, risk-informed, understandable 

and predictable approach to the oversight 

of nuclear power plant performance. The 

ROP supports the 

agency’s strategic 

goals for safety and 

security, and displays the 

organizational excellence 

values of openness and 

effectiveness. 

The process spells out 

clearly what a nuclear 

plant operator and the 

public can expect from 

the NRC with good plant 

performance and what can 

be expected from the NRC 

if performance declines.

Commercial nuclear power plants in the United States

Nuclear power plant

2

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Licensed to Operate (100)

REGION I

CONNECTICUT

Millstone 2 and 3

Calvert Cliffs 1 and 2

MASSACHUSETTS

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ALABAMA

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and 3

Farley 1 and 2

FLORIDA

St. Lucie 1 and 2

Turkey Point 3 and 4

REGION III

Braidwood 1 and 2

Byron 1 and 2

Clinton

Dresden 2 and 3

LaSalle 1 and 2

Quad Cities 1 and 2

REGION IV

ARKANSAS

Arkansas Nuclear 1

and 2

ARIZONA

Palo Verde 1, 2, and 3

CALIFORNIA

Diablo Canyon 1 and 2

= 2 units

= 1 units

= 3 units

MARYLAND

Pilgrim

ILLINOIS

IOWA

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PA

NY

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IN

WA

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U.S. Operating Commercial Nuclear Power Reactors

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Photo courtesy of Progress Energy
United States Nuclear Regulatory Commission

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The oversight process calls for:

• Focusing inspections on activities 

where the potential risks are greater.

• Increasing regulatory attention to 

nuclear power plants as performance 

declines, while maintaining a normal 

level of regulatory attention on facilities 

that perform well.

• Using objective measurements of 

nuclear power plant performance.

• Providing a timely and understandable 

assessment of plant performance to 

both the public and nuclear industry.

• Responding to violations of regulations 

in a predictable and consistent manner 

that reflects the potential safety impact 

of the violations.

REACTOR OVERSIGHT PROCESS 

CORNERSTONES

The ROP contributes to the NRC’s mission of 

ensuring public health and safety during the 

operation of commercial nuclear power plants 

by monitoring plant performance in three key 

areas:

• Reactor Safety—avoiding accidents and 

reducing the consequences of accidents if 

they occur

• Radiation Safety—for both plant workers 

and the public from unnecessary radiation 

exposure during routine operations, and 

• Safeguards—protection of the plant 

against sabotage or other security threats.

To monitor and measure plant performance, 

the oversight process focuses on seven 

“cornerstones” that support the safety of plant 

operations in the three key areas. These are 

described below. 

Reactor Safety Area

#1 Initiating Events: Any potential occurrence 

that could disrupt plant operations and 

challenge safety functions is an initiating 

event. This cornerstone focuses on limiting 

the occurrence of these type of events. These 

events could include equipment failures 

leading to a plant shutdown, shutdowns with 

unexpected complications, or large changes in 

the plant’s power output.

#2 Mitigating Systems: These are safety 

systems designed into each plant that alleviate 

the effects of initiating events. Mitigating 

systems can prevent an accident or reduce 

the consequences of a possible accident. This 

cornerstone monitors the function of these 

safety systems through periodic testing and 

actual performance.

#3 Barrier Integrity: There are three 

important barriers between the highly 

radioactive fuel inside the reactor and the 

public and the environment outside the 

plant. These barriers are: (1) the sealed rods 

containing the fuel pellets, (2) the heavy steel 

reactor vessel and associated piping, and (3) 

the reinforced concrete containment structure 

surrounding the reactor. The integrity of 

the fuel rods, the vessel, and the piping is 

continuously checked for leakage, while the 

ability of the containment structure to prevent 

leakage is measured on a regular basis.

#4 Emergency Preparedness: Each nuclear 

plant is required to have comprehensive 

emergency plans to effectively respond to a 

possible accident. This cornerstone measures 

the effectiveness of the plant staff in carrying 

out emergency plans. Such emergency plans 

are tested every 2 years involving plant staff 

as well as local, State, and, in some cases, 

Federal agencies. The plant staff itself 

conducts emergency exercises even more 

frequently.
R E A C T O R O V E R S I G H T P R O C E S S 

3

Radiation Safety Area

#5 Occupational Radiation Safety: NRC 

regulations set a limit on radiation doses 

received by plant workers. Exposures could 

be from poorly controlled or uncontrolled 

radiation areas or radioactive materials 

located at the plant. This cornerstone 

monitors the effectiveness of the plants’ 

program to control and minimize those doses.

#6 Public Radiation Safety: NRC regulations are 

designed to protect public health and safety from 

exposure to radioactive materials that may be 

released into the public domain. This cornerstone 

measures the procedures and systems designed 

to minimize radioactive releases from a nuclear 

plant during normal operations and to keep those 

releases within Federal limits.

Safeguards Area

#7 Security: Nuclear plants are required to 

have well-trained security personnel and a 

variety of protective systems to guard vital 

plant equipment, as well as programs to 

assure that employees are constantly fit for 

duty through drug and alcohol testing. This 

cornerstone measures the effectiveness of the 

security and fitness-for-duty programs.

Although the NRC actively oversees the security 

and safeguards activities and facilities at 

nuclear plants, the inspection and assessment 

information is not publicly available to ensure 

that potentially useful information is not 

provided to a possible adversary (only the cover 

letter is publicly available).

CROSS-CUTTING AREAS

In addition to the cornerstones, the ROP features 

three “cross-cutting” areas, so named because 

they can affect each of the cornerstones across 

all the key areas. 

These are:

•	 Human Performance—This area 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 area monitors the licensee’s 

corrective action and operating experience 

programs, and the licensee’s self- and 

independent-assessments. 

•	 Safety-Conscious Work Environment—

This area 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 crosscutting areas have an important role in the 

ROP. They are considered during all NRC 

inspections and are covered during periodic 

plant assessments.

Reactor Oversight Framework

Protect Public Health and Safety in the Use of Nuclear Power

Reactor Safety

Initiating

Events

Mitigating

Systems

Barrier

Integrity

Public 

Radiation

Security

Human Performance Problem Identification and Resolution Safety-Conscious Work Environment

Mission

Key Areas

Cornerstones

Cross-Cutting 

Areas

Occupational

Radiation

Emergency 

Preparedness

Radiation Safety Safeguards
United States Nuclear Regulatory Commission

4

Safety Cornerstone Performance Indicators

#1 Initiating Events •	 Unplanned reactor shutdowns (automatic and manual)

•	 Loss of normal reactor cooling system following unplanned shutdown

•	 Unplanned events that result in significant changes in reactor power

#2 Mitigating Systems •	 Safety system availability and reliability 

•	 Safety system failures

#3 Barrier Integrity •	 Fuel cladding (measured by radioactivity in reactor cooling system)

•	 Reactor cooling system leak rate

#4 Emergency Preparedness •	 Emergency response organization drill performance

•	 Readiness of emergency response organization

•	 Availability of notification system for area residents

#5 Occupational Radiation Safety •	 Unplanned radiation exposures to workers

#6 Public Radiation Safety •	 Effluent releases requiring reporting under NRC regulations and

 license conditions

#7 Security •	 Security system equipment availability

MEASURING AND INSPECTING 

NUCLEAR PLANT PERFORMANCE

Nuclear plant performance is measured and 

assessed by a combination of objective 

performance indicators reported by the 

licensee and by NRC inspection findings. 

They are both closely focused on those plant 

activities having the greatest impact on safety 

and overall risk. While performance indicators 

can provide insights into plant performance 

for selected areas, the NRC’s inspection 

program provides greater depth and breadth 

of information for consideration by the NRC in 

assessing plant performance.

In addition, the NRC conducts both periodic 

and annual reviews of the effectiveness of 

each utility’s programs to identify and correct 

problems. These programs, and their inputs 

and products, are described in more detail in 

the following sections. 

Performance Indicators

Each performance indicator has criteria for 

measuring acceptable performance. As in all 

industrial activities, nuclear power plants are 

not error-free or risk-free. Equipment problems 

and human errors will occur. Each performance 

indicator determines acceptable levels of 

operation within substantial safety margins. 

The criteria are designed to be objective 

and reflect risk according to established 

safety margins. Performance indicators 

for each cornerstone are shown in the 

following table. 

Inspection 

Findings

Performance 

Indicators + =

Plant 

Assessment
R E A C T O R O V E R S I G H T P R O C E S S 

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Page 5 : Performance Indicator Example Image

Page 4 Text: (idea on layout)

Performance + Inspection = Plant 

 Indicators Findings Assessment

Plant IE 

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Pilgrim 1 G G G G G G G G G G G G G G G G G

Perry 1 G G W G G G G G G G G G G G G G G

Example of performance indicators on the Web

Use of Performance Indicators

Each indicator is measured against the criteria 

using a color-coded system for safety 

performance.

The indicators are compiled by the licensee and 

reported to the NRC on a quarterly basis. Following 

compilation and review by the NRC staff, the 

quarterly performance indicators are posted on 

the NRC’s Web site: http://www.nrc.gov/NRR/

OVERSIGHT/ASSESS/pi_summary.html.

Inspection Program

The Reactor Oversight Process includes 

inspections by NRC staff with a variety of 

backgrounds and skills – among them are plant 

operations, engineering, radiation protection, 

emergency preparedness, and security.

Baseline inspections represent the minimum level 

of inspection required to ensure plant safety and 

security, and are common to all operating nuclear 

plants. The baseline inspection program is aligned 

to seven cornerstones and focuses on activities and 

systems that are “risk significant.” Risk significant 

activities and systems have a potential to trigger an 

accident, can mitigate the effects of an accident, or 

increase the consequences of a possible accident. 

Performance is assessed through information 

gained from performance indicators and NRC 

inspections.

The inspection program uses a “riskinformed” approach to select areas to inspect 

within each cornerstone. The inspection areas 

were chosen because of their importance to 

potential risk, past operational experience, 

and regulatory requirements. 

The baseline inspection program has three parts:

1. Inspection 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, and 

3. A thorough review of the licensee’s 

effectiveness in finding and resolving 

problems on its own

Inspections beyond the baseline program are 

performed in response to specific events at a 

plant or changes in the plant’s 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 

performance indicator data is evaluated 

and integrated with findings of the

NRC inspection program to provide a 

broad assessment of the plant’s safety 

performance.

Plant

Plant A

Plant B
United States Nuclear Regulatory Commission

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“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). 

Remaining inspection findings — which may 

be more than very low safety or security 

significance — are subjected to a more 

thorough risk assessment, using a more 

detailed evaluation. This detailed assessment 

may involve NRC risk experts from the 

appropriate regional office and further review 

by the utility’s plant staff. The final outcome of 

the review — evaluating whether the finding 

is green, white, yellow, or red — is used to 

determine further NRC actions that may be 

needed.

Quarterly Plant Assessments

Each calendar quarter, the resident inspectors 

and regional inspection staff review the 

performance of all nuclear power plants in 

that region, as measured by the performance 

indicators and by inspection findings. Every 6 

months this review involves a more detailed 

assessment of plant performance that includes 

staff from NRC headquarters, the regions, and 

resident inspectors as well as preparation of a 

performance report. Also every 6 months, based 

on plant performance reviews, NRC inspection 

plans for each reactor are determined for the 

following 18-month period.

For example, if a performance indicator or 

inspection finding shows increased safety 

significance, the NRC may conduct a special or 

supplemental inspection to review the situation 

and assess the effectiveness of the plant 

operator’s response. For more complicated 

situations, the agency may dispatch an 

“augmented” inspection team, bringing in added 

experts from other NRC regions or headquarters 

staff. For more serious events, a high-level 

“Incident Investigation Team” may be formed. 

The inspection program also includes review of 

cross-cutting areas of human performance, the 

“safety-conscious work environment,” and how 

the plant operator finds and fixes problems. This 

provides the ROP the ability to detect a decline in 

safety culture. 

The inspections are performed by NRC 

resident inspectors stationed full time at 

each nuclear power plant and by inspectors 

based in one of the four NRC regional offices 

or in NRC headquarters in Rockville, MD. The 

regional offices are located in King of Prussia, 

PA; Atlanta, GA; Lisle, IL; and Arlington, TX.

Inspection reports are issued for all 

inspections. Baseline inspection reports, 

compiled by the resident inspectors and 

inspection specialists are issued at the 

close of each calendar quarter. Special and 

supplemental inspection reports are issued 

several weeks after completion of those 

inspections. The inspection reports are 

available on the NRC’s Web site (http://www.

nrc.gov/NRR/OVERSIGHT/ASSESS/listofrpts_

body.html) , in the NRC’s online document 

collection Agencywide Documents Access and 

Management System (ADAMS), and from the 

Public Document Room at NRC headquarters. 

ASSESSMENT OF PLANT 

PERFORMANCE

Significance Determination Process

The staff uses a process, called the 

Green: indicates a finding of very low

safety or security significance

White:	 represents a finding of low to

moderate safety or security 

significance

Yellow: indicates a finding of substantial

safety or security significance

Red: is a finding of high safety or

security significance
R E A C T O R O V E R S I G H T P R O C E S S 

7

Annual Performance Reports and 

Public Meetings

Annual performance reports are available on 

the agency’s Web site at: http://www.nrc.gov/

NRR/OVERSIGHT/ASSESS/listofasmrpt.html. 

In addition, each year the NRC staff holds a 

public meeting with the licensee at each plant 

to discuss the previous year’s performance. 

This provides individuals living near the plant 

an opportunity to find out the status of a plant’s 

safety performance and talk with NRC staff.

Additionally, NRC senior management reviews 

the adequacy of agency actions for plants with 

a significant decrease in safety performance. 

The managers also take a wider view both 

of the overall industry performance and of 

the performance of the agency’s regulatory 

programs. The performance of plants requiring 

heightened agency scrutiny is then discussed 

during a public meeting with the NRC 

Commissioners at the agency’s Rockville, MD, 

headquarters.

NRC RESPONSE TO PLANT 

PERFORMANCE

The quarterly reviews of plant performance, 

using both the plant operator’s reported 

performance indicators and NRC inspection 

findings, determines what additional action, 

if any, the NRC will take if there are signs 

of declining performance. This approach 

is defined by the ROP’s Action Matrix. This 

matrix objectively ranks plant performance 

based on the significance of the inspection 

findings and performance indicators. The 

Action Matrix provides consistent, predictable, 

and understandable agency responses to 

licensee performance. As illustrated below, 

the NRC increases oversight as licensee 

performance declines. 

The process uses five levels of regulatory 

response with NRC regulatory review 

increasing as plant performance declines. 

The first three levels involve response by 

the appropriate regional office. The next two 

levels call for an agency response, involving 

senior management attention from both 

headquarters and regional offices. 

The ROP uses various tools for dealing with 

declining plant performance and violations. 

These tools are used in a predictable manner 

that is commensurate with the decreased 

safety performance. NRC actions may include 

meetings with the plant operator, additional 

inspections, and required stronger action by 

the agency, including an Order or even the 

suspension of the operating license. (See Below)

NRC Response

Response at Agency Level

Response at Agency Level 

• Meeting with NRC Executive Director for Operations and senior plant 

management 

• Plant operator improvement plan with NRC oversight 

• NRC team inspection focused on performance issues at the site 

• Demand for Information, Confirmatory Action Letter, or Order 

Response at Regional Level 

• Meeting with NRC regional management and senior plant management

• Plant operator self-assessment with NRC oversight 

• Additional NRC inspections focused on cause of degraded performance

Response at Regional Level 

• Meeting with NRC and plant management 

• Plant operator corrective actions to address WHITE inputs 

• NRC inspection to follow up on WHITE inputs and corrective actions

Normal Regional Oversight 

• Routine inspector and staff interaction

• Baseline inspection program 

• Annual assessment public meeting

ROP Action Matrix Asessment of Plant Performance

Column 5. Unacceptable Performance

Column 4. Multiple/Repetitive Degraded Cornerstone

Repetitive degraded cornerstone, multiple 

degraded cornerstones, or multiple YELLOW

inputs, or one RED input 

Column 3. Degraded Cornerstone One degraded 

cornerstone (two WHITE inputs or one YELLOW

input or three WHITE inputs in any strategic area) 

Column 2. Regulatory Response No more than two 

WHITE inputs in different cornerstones 

Column 1. Licensee Response All performance indicators 

and cornerstone inspection findings GREEN

Increasing Safety SignificanceIncreasing Regulatory Oversight
United States Nuclear Regulatory Commission

8

VIOLATIONS OF NRC 

REQUIREMENTS

Each violation of NRC requirements found 

during NRC inspections is evaluated to 

determine its effect on plant safety and risk. If 

the violation is of very low safety significance, 

it is discussed in NRC’s inspection report 

with no formal enforcement action. Through 

its corrective action program, the plant 

operator is expected to deal with the violation, 

correcting the violation and taking steps to 

prevent a recurrence. The issue may also be 

reviewed during future NRC inspections.

If the NRC risk evaluation finds that the 

violation has higher safety significance, a 

Notice of Violation will be issued. A Notice of 

Violation may also be issued if the licensee 

fails to correct a violation of low safety 

significance in a reasonable period of time or 

if a violation is found to be willful. 

The Notice of Violation requires the plant 

operator to formally respond to the NRC, 

identifying its actions to correct the violation and 

what steps it will take to prevent the violation 

from occurring again. The agency then reviews 

the operator’s actions in a later inspection.

Normally, these violations are not the subject 

of a fine. However, some violations may 

warrant a fine because of their unusual 

significance. These violations are likely to 

be uncommon. Possible examples include 

exceeding a safety limit specified in a reactor 

license or the inadvertent startup of a reactor.

In addition, some violations call for the 

traditional enforcement approach, including 

the possible issuance of fines. 

Examples include:

• 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

PERFORMANCE INFORMATION 

AVAILABLE TO THE PUBLIC

Information on plant performance is updated 

each quarter on the NRC’s Web site where 

performance histories and inspection findings 

are also available. Full inspection reports are 

available on the Web site, in the NRC’s online 

document collection called “ADAMS,” and from 

the NRC’s Public Document Room.

The performance indicators and the 

assessment of inspection findings are placed 

on the NRC Web site using the color notation 

of their significance: green, white, yellow, 

or red. The statistics and NRC inspection 

findings that underlie the color notation are 

also posted on the Web site. 

The ROP is instrumental to the NRC’s highest 

priority and commitment to the day-to-day 

business of overseeing operating reactors to 

make sure they continue to operate safely.

Additional information on the Reactor 

Oversight Process is available at the NRC’s 

Web site at: http://www.nrc.gov/NRR/

OVERSIGHT/ASSESS/index.html.
R E A C T O R O V E R S I G H T P R O C E S S 

9

Step 1

Click here on plant name

http://www.nrc.gov/NRR/OVERSIGHT/ASSESS/index.html

Step 2

Step 3

Click here for details

Click here for details

PERFORMANCE INFORMATION ON NRC WEB PAGES
United States Nuclear Regulatory Commission

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GLOSSARY

ADAMS: Agencywide Documents Access and 

Management System.

Baseline Inspection Program: The normal 

inspection program performed at all nuclear 

power plants. The program will focus on plant 

activities that are not adequately measured 

by performance indicators, on the corrective 

action program, and on verifying the accuracy 

of the performance indicators.

Cornerstone of Safety: Nuclear plant activities 

that are essential for the safe operation of the 

facility. These cornerstones are grouped under 

the categories of reactor safety, radiation 

safety, and safeguards.

Corrective Action Program: The system by 

which a utility finds and fixes problems at 

the nuclear plant. It includes a process for 

evaluating the safety significance of the 

problems, setting priorities in correcting the 

problems, and tracking them until they have 

been corrected.

Cross-cutting Area: Nuclear plant activity 

that affects most or all safety cornerstones. 

These include the plant’s cornerstone action 

program, human performance, and “safetyconscious work environment.”

Inspection Reports: Reports are issued 

periodically to document inspection findings. 

These may cover a specific time period for the 

baseline inspection or a particular event or 

problem examined in a reactive inspection. All 

inspection reports are public documents and, 

when issued, are posted to the U.S. Nuclear 

Regulatory Commission’s (NRC’s) Internet 

Web site.

Performance Indicator: Objective data that 

records performance in a specific cornerstone 

of safety at a nuclear power plant.

Reactive Inspection: An inspection to examine 

the circumstances surrounding an operational 

problem or event occurring at a nuclear plant.

Reactor Oversight Process: The NRC’s 

program to inspect, evaluate, and assess the 

safety performance of commercial nuclear 

power plants.

Regulatory Conference: A meeting between the 

NRC staff and a utility to discuss potential safety 

issues or to discuss a change in performance as 

indicated by a declining performance indicator 

or inspection finding. These meetings are open 

to public observation unless they cover security 

issues, NRC investigation findings, or similar 

sensitive topics.

Resident Inspector: An NRC inspector 

assigned to a nuclear plant on a full-time 

basis. Each site has at least two resident 

inspectors.

Risk-informed: Incorporating an assessment 

of safety significance or relative risk in NRC 

regulatory actions.

Safety Culture: The set of core values 

and behaviors resulting from a collective 

commitment by leaders and individuals to 

emphasize safety over competing goals 

to ensure protection of people and the 

environment.

Significance Determination Process: The 

process used by the NRC staff to evaluate 

inspection findings to determine their safety 

significance. This involves assessing how 

much the inspection findings increase the risk 

of nuclear operations.

United States 

Nuclear Regulatory Commission

NUREG-1649, Rev. 5

February 2014