[7590-01-P] 

United States Nuclear Regulatory Commission 

NRC-2008-0237 

Policy Statement on the Regulation of Advanced Reactors 

AGENCY: Nuclear Regulatory Commission. 

ACTION: Final policy statement. 

SUMMARY: On May 9, 2008 (73 FR 26349), the Nuclear Regulatory Commission (NRC; 

Commission) issued, for public comment, a draft policy statement on the regulation of advanced 

reactors. This final policy statement reinforces the Commission’s current policy regarding 

advanced reactors and includes new items to be considered during the design of these reactors, 

including security, emergency preparedness, threat of theft, and international safeguards. 

DATE: The effective date is (Insert date 30 days after the date of publication) 

FOR FURTHER INFORMATION CONTACT: Mr. Wesley W. Held, Rulemaking, Guidance, 

and Advanced Reactor Branch, Division of New Reactor Licensing, Office of New Reactors, 

U.S. Nuclear Regulatory Commission, Mail Stop: T-6 C34, Washington, DC 20555-0001; 

Telephone: (301) 415-1583; fax number: (301) 415-5399; e-mail: Wesley.Held@nrc.gov. 

SUPPLEMENTARY INFORMATION:

I. Background 

II. Summary of Public Comments and Responses to Comments 

A. General Comments 

B. Attributes to Be Considered During Design 

C. Security of Advanced Reactors 
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D. Relationship to General Design Criteria (GDC) 

E. Other Comments 

III. Final Policy Statement

I. Background

 On July 8, 1986 (51 FR 24643), the Commission published a policy statement on the 

regulation of advanced reactors. The Commission had the following three primary objectives in 

issuing the advanced reactor policy statement (ARPS): 

• To maintain the earliest possible interaction of applicants, vendors, and 

government agencies with the NRC. 

• To provide all interested parties, including the public, with the Commission’s 

views concerning the desired characteristics of advanced reactor designs. 

• To express the Commission’s intent to issue timely comment on the implications 

of such designs for safety and the regulatory process. 

 On July 12, 1994 (59 FR 35461), the Commission revised the 1986 ARPS by addressing 

the Commission’s policy on metrication (57 FR 46202; October 7, 1992; as revised June 19, 

1996 (61 FR 31169)). 

 Since the events of September 11, 2001, the NRC has assessed potential threats and 

their possible impacts on the Nation’s fleet of operating nuclear power reactors and has required 

upgrades of physical security measures and mitigative strategies through the issuance of a 

series of security orders and license conditions. For new nuclear power reactors, the 

Commission considers it prudent to provide expectations and guidance on security matters to 

prospective applicants so that they can use this information early in the design stage of new 

reactors to identify potential mitigative measures and/or design features that provide a more 

robust and effective security posture. Therefore, the Commission decided to revise the ARPS 
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to integrate these expectations for security and emergency preparedness with the current 

expectations for safety. 

 The Commission’s expectation for advanced reactor designers to consider the effects of 

a large, commercial airplane impact is currently being addressed through rulemaking 

(Consideration of Aircraft Impacts for New Nuclear Power Reactor Designs—RIN AI19—Docket 

ID NRC-2007-0009). The Commission believes that reactors designed with potential aircraft 

impact considerations resulting from this rule would be more robust than if they were designed 

in the absence of this rule. 

 The proposed policy statement, “Policy Statement on the Regulation of Advanced 

Reactors,” was published in the Federal Register on May 9, 2008 (73 FR 26349). The public 

comment period expired on July 8, 2008. This final policy statement reflects the pertinent 

comments received on the published draft policy statement. 

II. Summary of Public Comments and Responses to Comments 

 Eight organizations and individuals submitted written comments on the draft policy 

statement. The commenters represented a variety of interests addressing a wide range of 

issues, and included individuals; reactor vendors; and citizen, environmental, and industry 

groups. Most commenters agreed with the general principle of the policy statement, but no 

commenter supported the policy statement exactly as proposed. Several commenters wanted 

changes made to the list of design attributes to be considered. Others suggested linking the 

design attributes to the general design criteria (GDC). Another commented on the security of 

nuclear power plants, and one commenter described a thorium reactor design. 

 Comments on this proposed rule are available electronically at 

http://www.regulations.gov. From this page, the public can find all the comments received by 

inputting NRC-2008-0237 into the search field. Comments are also available electronically at 
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the NRC's Electronic Reading Room at http://www.nrc.gov/reading-rm/adams.html. From this 

page, the public can gain access to the Agencywide Documents Access and Management 

System (ADAMS), which provides text and image files of NRC's public documents. The public 

can search for comments using the ADAMS accession numbers listed in the table below, which 

includes the commenters’ names and affiliations. 

Letter 

No. 

ADAMS 

Accession 

No. Commenter Affiliation Commenter Name Abbreviation 

1 ML081420201 Private citizen Paul Sund Sund 

2 ML081420208 University of California - Berkeley Per Peterson UCB 

3 ML081770159 Toshiba Koichiro Oshima Toshiba 

4 ML081900560 Thorium ElectroNuclear AB Elling Disen TEN AB 

5 ML081900562 

North Carolina Waste Awareness 

and Reduction Network John D. Runkle NC WARN 

6 ML081910787 Nuclear Energy Institute Adrian Heymer NEI 

7 ML081910796 Union of Concerned Scientists Edwin Lyman UCS 

8 ML081970378 Private citizen Ray Van De Walker Walker 

 This document places each public comment into one of the following categories: 

 A. General Comments 

 B. Attributes to Be Considered During Design 

 C. Security of Advanced Reactors 

 D. Relationship to GDC 

 E. Other Comments 

 Within each category, the NRC has either repeated comments as written by the 

commenter or summarized the comments for conciseness and clarity. At the end of the 

comment or comment summary, the NRC references the specific public comments and the 

letters by which they were provided to the NRC using the NRC-assigned sequential comment 

numbers listed in Table 1. For example, specific comments are referenced as [XXX]-[YYY], 
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where [XXX] represents the commenter’s abbreviation and [YYY] represents the NRC-assigned 

sequential comment number. 

A. General Comments 

Comment: The commenter believes that a fast fuel reactor can help reduce the volume 

of radioactive waste currently in storage at reactor sites in the United States and hopes that the 

NRC has considered or will consider those designs. (Sund-1) 

NRC Response: The NRC neither develops nor promotes reactor designs, but rather 

reviews the safety and security aspects of designs proposed by reactor vendors and designers. 

The NRC has the ability to develop the capability to evaluate innovative and advanced designs 

that are presented for NRC review (e.g., Toshiba’s 4S reactor design). No changes were made 

to the policy statement as a result of this comment. 

Comment: The commenter suggests that the term “current generation” in the first 

paragraph of the policy statement could be misinterpreted because it was written in 1986 and 

does not take into consideration plants currently in the licensing process. The commenter 

suggests that the term “current generation light-water reactors” be replaced with “plants licensed 

before 1997.” (NEI-2) 

NRC Response: The NRC agrees that the term “current generation” may cause 

confusion because it is subjective and time-dependent. During previous interactions with the 

industry, the staff indicated that “current generation light-water reactors” refers to those reactors 

that were licensed before 1997. Accordingly, a footnote has been added to Section III, “Final 

Policy Statement,” providing this definition. 

Comment: The commenter suggests that the discussion of the pending rulemaking on 

Consideration of Aircraft Impacts for New Nuclear Plant Designs (Rulemaking Docket 

NRC-2007-0009) is more akin to background information than a lasting statement of 
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Commission policy and recommends deleting this paragraph or relocating it to the Background 

section. (NEI-3) 

NRC Response: The NRC agrees with the comment and has moved the discussion to 

the Background section in order to alleviate the need to revise the statement again as that 

rulemaking progresses. 

Comment: The commenter states that the NRC licensing review is a famously difficult 

hurdle for advanced reactors and wants the Commission to consider a pilot program where 

commercial bureaus would use NRC policies to review, license, and inspect new reactor 

designs. (Walker-1) 

NRC Response: The Atomic Energy Act of 1974, as amended, describes the NRC’s 

responsibilities. These responsibilities include the licensing of nuclear reactors; therefore, the 

NRC cannot transfer this responsibility to another entity. No changes were made to the policy 

statement as a result of this comment. 

Comment: The commenter encourages “type-licensing” of reactor designs and 

“fast-track combined operating licenses.” (Walker-2) 

NRC Response: The NRC generally agrees with the comment. As the commenter 

noted, the NRC has regulations in place that allow these regulatory approval processes. In 

10 CFR Part 52, “Licenses, Certifications, and Approvals for Nuclear Power Plants,” the NRC 

uses the term “design certification” to describe the process of approving by rulemaking a reactor 

design that may be referenced by combined license (COL) applicants. A COL is a licensing 

process that results in the granting of a combined construction permit and operating license with 

conditions. This process is different from the two-step process in 10 CFR Part 50, “Domestic 

Licensing of Production and Utilization Facilities,” which provides for construction permits and 

operating licenses. In addition to the benefits gained by using the COL process, the NRC has 
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also developed a design-centered approach for COL reviews that implements a “one issue, one 

review, and one decision philosophy.” No changes were made to the policy statement as a 

result of this comment. 

Comment: The commenter believes that the overall effectiveness of the policy will be 

strengthened if the fourth listed attribute (and perhaps to a lesser degree, the eighth), 

emphasizes or prioritizes the potential for minimizing severe accidents over minimizing the 

consequences of such an accident. This may be a small distinction, but the commenter 

believes there is a benefit to initially focusing on features to prevent an accident although 

reactor designers should not overlook mitigation features. (Toshiba-1) 

NRC Response: The NRC agrees that accident prevention is preferable to accident 

mitigation and believes that the fourth attribute expresses this emphasis because the attribute 

lists design features that enhance prevention specifically. However, the attribute has been 

modified to place additional emphasis on accident prevention. 

Comment: The commenter notes that the policy statement makes no mention of the use 

of probabilistic risk assessment (PRA) in assessing the design of advanced reactors and feels 

that it would be helpful to describe how PRA might be used to confirm the favorable design 

attributes suggested. The commenter feels that it may be helpful to provide advanced reactor 

designers with interim guidance regarding NRC efforts for a risk informed, technology neutral 

licensing framework to permit designers to approach licensing with less uncertainty regarding if 

and/or how PRA should be utilized. (Toshiba-3) 

 NRC Response: The NRC has established specific requirements related to the use of 

PRA in licensing new nuclear power plants, which would be applicable to advanced reactors. 

For example, in accordance with 10 CFR 52.47, “Contents of Applications—Technical 

Information,” applicants for a design certification must include in their application a description of 
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the design-specific PRA and its results. In addition, 10 CFR 50.71(h) requires each holder of a 

COL to develop and maintain a PRA for their facility and to periodically update the PRA to 

reflect plant changes and any NRC-endorsed consensus standards on PRA. In addition to 

adopting these regulatory requirements, the Commission has also issued policy statements on 

the use of PRA in regulatory activities (60 FR 42622; August 16, 1995), and severe accidents 

regarding future designs and existing plants (50 FR 32138; August 8, 1985). The use of PRA 

as a design tool is implied by the policy statement on the use of PRA and the NRC believes that 

the current regulations and policy statements provide sufficient guidance to designers. No 

changes were made to the policy statement as a result of this comment. 

B. Attributes to Be Considered During Design 

Comment: The commenter recommends that the policy statement explicitly discuss the 

threat of theft, in addition to the current focus on threat of sabotage of facilities, and encourage 

designers to consider requirements for implementing international safeguards monitoring early 

in the design process, particularly for reactors that will be co-located with reprocessing facilities. 

The commenter suggested a possible addition to the list of design attributes included in the 

policy statement that relates to theft and international safeguards. (UCB-1) 

NRC Response: The NRC agrees with the comment and has added expectations that 

reactor designers consider the threat of theft and requirements for implementing international 

safeguards monitoring early in the design phase. An attribute has been added to the list of 

design attributes to be considered during the design of advanced reactors to address these 

topics. 

Comment: The commenter suggests that the following attributes in the current ARPS are 

not statements of design philosophy and are solely a restatement of existing regulations and 

should be deleted. 
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• Designs with features to prevent a simultaneous loss of containment integrity 

(including situations where the containment is bypassed), and the ability to 

maintain core cooling as a result of an aircraft impact, or identification of system 

designs that would provide inherent delay in radiological releases (if prevention of 

release is not possible). 

• Designs with features to prevent loss of spent fuel pool integrity as a result of an 

aircraft impact. (NEI-1) 

NRC Response: The NRC agrees that these attributes are restatements of current 

requirements, but it believes that these aspects should be highlighted in the policy statement to 

ensure that they are considered early in the design phase in order to identify design features 

that could be included to prevent or mitigate problems rather than relying on operational 

programs. No changes were made to the policy statement as a result of this comment. 

C. Security of Advanced Reactors 

Comment: The commenter agrees that advanced reactor designers should consider 

potential mitigative measures and/or design features that provide a more robust and effective 

security posture, which should include the possible threat of terrorist attacks and aviation 

attacks at any reactor. (NCWARN-1) 

NRC Response: As stated in the background section, the Commission’s expectation for 

advanced reactor designers to consider the effects of a large, commercial airplane impact is 

currently being addressed through rulemaking (Consideration of Aircraft Impacts for New 

Nuclear Power Reactor Designs—RIN AI19—ID Docket NRC-2007-0009). The Commission 

believes that reactors designed with potential aircraft impact considerations resulting from this 

proposed rule would be more robust than currently-licensed reactors. However, if the NRC 

adopts the aircraft impact rule in final form, it will be applicable to future reactor designs and 
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need not be addressed in this policy statement. Regarding terrorist attacks, as with operating 

and proposed reactors, all licensees – including those using advanced reactor designs must be 

able to defend against the design basis threat (DBT), which considers terrorist attacks. No 

changes were made to the policy statement as a result of this comment. 

Comment: The commenter states that it can be concluded from the wording of the 

ARPS that existing reactors and reactors currently being proposed (AP1000, ESBWR, etc.) do 

not address possible threats of terrorist attacks and aviation attacks in any meaningful way. 

(NCWARN-2) 

NRC Response: The NRC disagrees with the comment. All operating reactors must be 

able to defend against the DBT, which considers terrorist attacks. The NRC conducts both 

routine security inspections and force-on-force exercises to ensure that the security plans at 

each plant are sufficient enough to successfully defend against the DBT. In addition, the NRC 

issued orders in 2002 to all operating reactors requiring them to implement measures to mitigate 

the effects of the loss of large areas of a plant caused by large fires and explosions. Those 

orders are currently being codified and once finalized will be requirements for new reactors as 

well. No changes were made to the policy statement as a result of this comment. 

Comment: The commenter states that it seems an untenable position by the 

Commission to recognize that "advance reactors" need to be made safer, more robust and 

effective, yet ignore the clear message it is sending the public on the lack of safety at the 

current reactors and proposed reactors. The commenter provided a list of attributes that he 

feels should be required for current reactors and proposed reactors that includes many of the 

items listed in the policy statement as appropriate for consideration for advanced reactors. 

(NCWARN-3) 
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NRC Response: The NRC disagrees with the comment. The policy statement does not 

state that advanced reactor designs must be safer than the current generation of reactors, but 

rather that they must provide the same degree of protection of the environment and public 

health and safety and the common defense and security that is required for current-generation 

light-water reactors. The goal of the policy statement update is to encourage advanced reactor 

designers to consider safety and security in the early stages of design in order to identify 

potential design features and/or mitigative measures that provide a more robust and effective 

security posture with less reliance on operational programs. No changes were made to the 

policy statement as a result of this comment. 

Comment: The commenter believes that current reactors and proposed reactors need to 

have attributes similar to those noted in the policy statement for advanced reactors. In addition, 

the commenter believes that the Commission needs to guarantee that all current reactors meet 

these minimal safety requirements as a top priority, and then ensure that the designs for the 

proposed reactors meet these requirements prior to the issuance of any new reactor license. 

(NCWARN-4) 

NRC Response: The attributes listed in the policy statement are ones that the NRC 

believes should be considered during the design stage of advanced reactors. Although some of 

the attributes reflect those found in current requirements, not all of them are requirements. The 

NRC believes that it would be impractical to force existing reactors to modify their designs to 

include all of the design attributes in the Advanced Reactor Policy Statement. Such changes 

would essentially result in those plants being completely redesigned. There is no need for such 

a drastic step, given that the NRC continues to believe that all currently operating reactors 

provide reasonable assurance of adequate protection. No changes were made to the policy 

statement as a result of this comment. 
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Comment: The commenter states that none of the existing reactors are safe and secure 

and that advanced reactors can wait until present deficiencies are fixed and proposed reactors 

are made safe and secure. (NCWARN-5) 

NRC Response: The NRC believes that the existing fleet of nuclear power plants is 

safe and secure. The NRC also believes that advanced reactor designers should consider the 

expectations in the policy statement to ensure that security and emergency response are 

considered alongside safety during the early stages of plant design. The fact that such actions 

might reduce the need for operator actions or improve the overall risk profile for future plants 

does not mean that the existing operating plants are unsafe. No changes were made to the 

policy statement as a result of this comment. 

D. Relationship to General Design Criteria (GDC) 

Comment: The commenter wants the agency to incorporate the ‘expectations’ in the 

policy statement into the regulations as additional GDC. (UCS-1) 

NRC Response: The GDC establish minimum requirements for the principal design 

criteria for nuclear power plants. The goal of the policy statement is not to raise these minimum 

requirements, but rather to encourage advanced reactor designers to consider safety and 

security matters during the development of future reactor designs. No changes were made to 

the policy statement as a result of this comment. 

Comment: The commenter believes that the utility of the policy could be enhanced if the 

relationship of the attributes listed in the policy to the GDC of 10 CFR Part 50, Appendix A is 

provided. (Toshiba-2) 

NRC Response: The NRC believes that the attributes identified in the policy statement 

should be used in conjunction with the GDC, other NRC regulations, and sound design 

practices to ensure that safety and security are appropriately considered in the design. The 
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attributes do not necessarily correspond to any particular GDC or set of GDCs, and it is not 

clear what benefit would be obtained if the NRC were to now identify “relationships” between the 

design attributes and the GDC. No changes were made to the policy statement as a result of 

this comment. 

E. Other Comments 

Comment: The commenter did not submit comments on the draft revision to the ARPS, 

but instead submitted information on a thorium reactor design. (TEN AB-1) 

NRC Response: The commenter did not address any topic of the draft revision to the 

policy statement, nor did the comment explain why it should include design information on a 

specific design concept. No changes were made to the policy statement as a result of this 

comment. 

III. Final Policy Statement

Consistent with its legislative mandate, the Commission’s policy with respect to 

regulating nuclear power reactors is to ensure adequate protection of the environment and 

public health and safety and the common defense and security. Regarding advanced reactors, 

the Commission expects, as a minimum, at least the same degree of protection of the 

environment and public health and safety and the common defense and security that is required 

for current generation light-water reactors (LWRs).1

 Furthermore, the Commission expects that 

advanced reactors will provide enhanced margins of safety and/or use simplified, inherent, 

passive, or other innovative means to accomplish their safety and security functions. 

Among the attributes that could assist in establishing the acceptability or licensability of 

a proposed advanced reactor design, and therefore should be considered in advanced designs, 

are: 

 

1

 Current generation LWRs are those nuclear power plants licensed before 1997. 
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• Highly reliable and less complex shutdown and decay heat removal systems. 

The use of inherent or passive means to accomplish this objective is encouraged 

(negative temperature coefficient, natural circulation, etc.). 

• Longer time constants and sufficient instrumentation to allow for more diagnosis 

and management before reaching safety systems challenge and/or exposure of 

vital equipment to adverse conditions. 

• Simplified safety systems that, where possible, reduce required operator actions, 

equipment subjected to severe environmental conditions, and components 

needed for maintaining safe shutdown conditions. Such simplified systems 

should facilitate operator comprehension, reliable system function, and more 

straightforward engineering analysis. 

• Designs that minimize the potential for severe accidents and their consequences 

by providing sufficient inherent safety, reliability, redundancy, diversity, and 

independence in safety systems, with an emphasis on minimizing the potential 

for accidents over minimizing the consequences of such accidents. 

• Designs that provide reliable equipment in the balance of plant (BOP) (or safetysystem independence from BOP) to reduce the number of challenges to safety 

systems. 

• Designs that provide easily maintainable equipment and components. 

• Designs that reduce potential radiation exposures to plant personnel. 

• Designs that incorporate the defense-in-depth philosophy by maintaining multiple 

barriers against radiation release, and by reducing the potential for, and 

consequences of, severe accidents. 

• Design features that can be proven by citation of existing technology, or that can 
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be satisfactorily established by commitment to a suitable technology 

development program. 

• Designs that include considerations for safety and security requirements together 

in the design process such that security issues (e.g., newly identified threats of 

terrorist attacks) can be effectively resolved through facility design and engineered 

security features, and formulation of mitigation measures, with reduced reliance on 

human actions. 

• Designs with features to prevent a simultaneous loss of containment integrity 

(including situations where the containment is by-passed), and the ability to 

maintain core cooling as a result of an aircraft impact, or identification of system 

designs that would provide inherent delay in radiological releases (if prevention of 

release is not possible). 

• Designs with features to prevent loss of spent fuel pool integrity as a result of an 

aircraft impact. 

• Designs with features to eliminate or reduce the potential theft of nuclear 

materials. 

• Designs that emphasize passive barriers to potential theft of nuclear materials. 

If specific advanced reactor designs with some or all of the previously mentioned 

attributes are brought to the NRC for comment and/or evaluation, the Commission can develop 

preliminary design safety evaluation and licensing criteria for their safety-related and 

security-related aspects. Incorporating the above attributes may promote more efficient and 

effective design reviews. However, the listing of a particular attribute does not necessarily 

mean that specific licensing criteria will attach to that attribute. Designs with some or all of 

these attributes are also likely to be more readily understood by the general public. Indeed, the 
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number and nature of the regulatory requirements may depend on the extent to which an 

individual advanced reactor design incorporates general attributes such as those listed 

previously. 

In addition, the Commission expects that the safety features of these advanced reactor 

designs will be complemented by the operational program for Emergency Planning (EP). This 

EP operational program, in turn, must be demonstrated by inspections, tests, analyses, and 

acceptance criteria to ensure effective implementation of established measures. The 

Commission also expects that advanced reactor designs will comply with the Commission's 

safety goal policy statement (51 FR 28044; August 4, 1986, as corrected and republished at 

51 FR 30028; August 21, 1986), and the policy statement on conversion to the metric 

measurement system (61 FR 31169; June 19, 1996). 

To provide for more timely and effective regulation of advanced reactors, the 

Commission encourages the earliest possible interaction of applicants, vendors, other 

government agencies, and the NRC to provide for early identification of regulatory requirements 

for advanced reactors and to provide all interested parties, including the public, with a timely, 

independent assessment of the safety and security characteristics of advanced reactor designs. 

Such licensing interaction and guidance early in the design process will contribute towards 

minimizing complexity and adding stability and predictability in the licensing and regulation of 

advanced reactors. 

While the NRC does not develop new reactor designs, the Commission intends to 

develop the capability, when appropriate, for timely assessment and response to innovative and 

advanced reactor designs that might be presented for NRC review. Prior experience has shown 

that new reactor designs - even variations of established designs - may involve technical 

problems that must be solved to ensure adequate protection of the public health and safety. 
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The earlier these design problems are identified, the earlier satisfactory resolution can be 

achieved. Prospective applicants are reminded that, while the NRC will undertake to review and 

comment on new design concepts, the applicants are responsible for documentation and 

research necessary to support a specific application. Research activities would include testing 

of new safety or security features that differ from existing designs for operating reactors, or that 

use simplified, inherent, passive means to accomplish their safety or security function. The 

testing shall ensure that these new features will perform as predicted, will provide for the 

collection of sufficient data to validate computer codes, and will show that the effects of system 

interactions are acceptable. 

During the initial phase of advanced reactor development, the Commission particularly 

encourages design innovations that enhance safety, reliability, and security (such as those 

described previously) and that generally depend on technology that is either proven or can be 

demonstrated by a straightforward technology development program. In the absence of a 

significant history of operating experience on an advanced concept reactor, plans for the 

innovative use of proven technology and/or new technology development programs should be 

presented to the NRC for review as early as possible, so that the NRC can assess how the 

proposed program might influence regulatory requirements. 
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Finally, the NRC also believes that it will be in the interest of the public as well as the 

design vendors and the prospective license applicants to address security issues early in the 

design stage to achieve a more robust and effective security posture for future nuclear power 

reactors. 

Dated at Rockville, Maryland, this 7th day of October 2008. 

 For the Nuclear Regulatory Commission. 

 /RA/ 

 Annette L. Vietti-Cook, 

 Secretary of the Commission.