1 Copies are available for inspection or copying for a fee from the NRC Public Document Room at 11555 Rockville MD; the

PDR’s mailing address is Mail Stop PDR, Washington, DC 20555; telephone (301) 415-4737 or (800)397-4209; fax (301)415-

3548; email <PDR@NRC.GOV>.

Regulatory guides are issued to describe and make available to the public such information as methods acceptable to the NRC staff for implementing specific parts

of the NRC’s regulations, techniques used by the staff in evaluating specific problems or postulated accidents, and data needed by the NRC staff in its review of

applications for permits and licenses. Regulatory guides are not substitutes for regulations, and compliance with them is not required. Methods and solutions different

from those set out in the guides will be acceptable if they provide a basis for the findings requisite to the issuance or continuance of a permit or license by the

Commission.

This guide was issued after consideration of comments received from the public. Comments and suggestions for improvements in these guides are encouraged

at all times, and guides will be revised, as appropriate, to accommodate comments and to reflect new information or experience. Written comments may be submitted

to the Rules and Directives Branch, ADM, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001.

Regulatory guides are issued in ten broad divisions: 1, Power Reactors; 2, Research and Test Reactors; 3, Fuels and Materials Facilities; 4, Environmental and Siting;

5, Materials and Plant Protection; 6, Products; 7, Transportation; 8, Occupational Health; 9, Antitrust and Financial Review; and 10, General.

Single copies of regulatory guides (which may be reproduced) may be obtained free of charge by writing the Distribution Services Section, U.S. Nuclear Regulatory

Commission, Washington, DC 20555-0001, or by fax to (301)415-2289, or by email to DISTRIBUTION@NRC.GOV. Electronic copies of this guide are available

on the internet at NRC’s home page at <WWW.NRC.GOV> in the Reference Library under Regulatory Guides. This guide is also in the Electronic Reading Room

at NRC’s home page, along with other recently issued guides, Accession Number ML003759710.

U.S. NUCLEAR REGULATORY COMMISSION November 2000

REGULATORY

GUIDE

OFFICE OF NUCLEAR REGULATORY RESEARCH

REGULATORY GUIDE 1.187

(Draft was issued as DG-1095)

GUIDANCE FOR IMPLEMENTATION OF 10 CFR 50.59,

CHANGES, TESTS, AND EXPERIMENTS

A. INTRODUCTION

In 10 CFR Part 50, “Domestic Licensing of Production and Utilization Facilities,” Section

50.59, “Changes, Tests and Experiments,” contains requirements for the process by which licensees

may make changes to their facilities and procedures as described in the safety analysis report, without

prior NRC approval, under certain conditions. The rule was promulgated in 1962 and revised in 1968.

As a result of lessons learned from operating experience and other initiatives related to control

of conformance of facilities with their final safety analysis report (FSAR) descriptions, the NRC

determined that additional action was necessary to provide clarity and consistency in implementation

of the rule. The staff recommended specific actions in SECY-97-205, “Integration and Evaluation of

Results from Recent Lessons-Learned Reviews,”1 dated September 10, 1997. In a staff requirements

memorandum dated March 24, 1998,1 the Commission directed the staff to initiate rulemaking to

revise the requirements of 10 CFR 50.59 to clarify the requirements and to allow changes involving

only “minimal increases” in probability or consequences to be made without prior NRC approval.

The proposed rule was published for comment in October 1998. Following consideration of

public comments, on October 4, 1999 (64 FR 53582), the NRC issued a final revision to

10 CFR 50.59 that becomes effective 90 days after approval of regulatory guidance, which is
2 Copies of NEI 96-07 are available through NRC’s web site, <WWW.NRC.GOV> through NRC’s Electronic Reading Room,

under Accession Number ML003771157. Copies are available for inspection or copying for a fee from the NRC Public

Document Room at 11555 Rockville Pike, Rockville, MD; the PDR’s mailing address is Washington, DC 20555; telephone

(301)415-4737 or (800)397-4209; fax (301 415-3548; email <PDR@NRC.GOV>.

1.187-2

contained in this Regulatory Guide 1.187. The text of the revised rule is contained in Appendix A

to this regulatory guide for convenience.

The information collections contained in this regulatory guide are covered by the

requirements of 10 CFR Part 50, which were approved by the Office of Management and Budget,

approval number 3150-0011. If a means used to impose an information collection does not display

a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not

required to respond to, the information collection.

B. DISCUSSION

OBJECTIVE

The objectives of 10 CFR 50.59 are to ensure that licensees (1) evaluate proposed changes

to their facilities for their effects on the licensing basis of the plant, as described in the FSAR, and

(2) obtain prior NRC approval for changes that meet specified criteria as having a potential impact

upon the basis for issuance of the operating license. This regulatory guide, through its

endorsement of a guideline document for licensees, provides guidance on complying with the

revised requirements of 10 CFR 50.59.

DEVELOPMENT OF INDUSTRY GUIDELINE, NEI 96-07

Following publication of the revised rule, the Nuclear Energy Institute (NEI) submitted a

guidance document for the implementation of 10 CFR 50.59 and requested NRC endorsement

through a regulatory guide. Following a series of meetings between NEI and the NRC, a revised

version of the guidance document was submitted by NEI on February 22, 2000. The NRC

published for public comment a Draft Regulatory Guide, DG-1095, which endorsed, with certain

clarifications, Revision 1 of NEI 96-07. As part of their comments in response to the draft guide,

NEI proposed revisions to NEI 96-07 to respond to the issues raised by the NRC staff in its draft

guide. Subsequently, NEI submitted a revised version of NEI 96-07, dated November 2000, for

endorsement.

C. REGULATORY POSITION

1. NEI 96-07

Revision 1 of NEI 96-07, “Guidelines for 10 CFR 50.59 Evaluations,”2 dated November

2000, provides methods that are acceptable to the NRC staff for complying with the provisions of

10 CFR 50.59.
1.187-3

2. OTHER DOCUMENTS REFERENCED IN NEI 96-07

Revision 1 of NEI 96-07 references other documents, but NRC’s endorsement of Revision

1 should not be considered an endorsement of the referenced documents.

3. USE OF EXAMPLES IN NEI 96-07

Revision 1 of NEI 96-07 includes examples to supplement the guidance. While

appropriate for illustrating and reinforcing the guidance in Revision 1 of NEI 96-07, the NRC’s

endorsement of Revision 1 should not be considered a determination that the examples are

applicable for all licensees. A licensee should ensure that an example is applicable to its particular

circumstances before implementing the guidance as described in an example.

4. GUIDANCE FOR FSAR SUPPLEMENTS FOR LICENSE RENEWAL

The guidance in Revision 1 of NEI 96-07 and in this regulatory guide is applicable to

information added to the FSAR in accordance with 10 CFR 54.21(d), that is, for summary

descriptions of the programs and activities for managing the effects of aging and the evaluation of

time-limited aging analyses.

5. APPLICABILITY TO NON-POWER REACTORS

While most of the examples and specific discussion focus on power reactors, the guidance

contained in Revision 1 of NEI 96-07 is also applicable to evaluations performed by licensees for

non-power reactors. Certain of the provisions in the guidance that discuss the relationship of other

regulatory requirements to 10 CFR 50.59 may not be fully applicable to non-power reactors

because of differences in those other requirements. For example, non-power reactors are not

subject to 10 CFR 50.65, and thus, the guidance concerning use of risk assessments for temporary

alterations associated with maintenance in lieu of 10 CFR 50.59 reviews would not be applicable.

6. APPLICABILITY TO 10 CFR 72.48 EVALUATIONS

The guidance contained in Revision 1 of NEI 96-07 is also generally applicable to

evaluations performed by licensees of independent spent fuel storage facilities (ISFSIs) or spent

fuel storage cask design certificate holders for implementation of the revised 10 CFR 72.48. The

NRC plans to issue guidance that would endorse (with comment if needed) a companion industry

guidance document that has adjustments to the examples and other specific aspects as they pertain

to 10 CFR 72.48.

7. APPLICABILITY OF PAST NRC COMMUNICATIONS

The NRC has issued a number of communications such as Generic Letters or Bulletins that

discussed or referred to 10 CFR 50.59. In considering whether the information in those documents

remains applicable, it should be noted that those documents were based on the rule requirements

that existed at the time of issuance. To the extent that the discussion therein relates to specific

aspects of the rule, such as evaluation criteria that have been revised, these past documents may no
1.187-4

longer be fully consistent and the new rule requirements would prevail. The status is unchanged of

other parts of these documents that are not affected by the revisions to the rule.

8. USE OF OTHER METHODS

To meet the requirements of 10 CFR 50.59, licensees may use methods other than those set

forth in Revision 1 of NEI 96-07. The NRC will determine the acceptability of other methods on a

case-by-case basis.

D. IMPLEMENTATION

The purpose of this section is to provide information to licensees and applicants regarding

the NRC staff’s plans for using this regulatory guide.

Except in those cases in which a licensee proposes an acceptable alternative method for

complying with the specified portions of the NRC’s regulations, the methods described in this

guide will be used in the evaluation of licensee compliance with the requirements of

10 CFR 50.59.
1.187-A-1

APPENDIX A

TEXT OF 10 CFR 50.59

§ 50.59 Changes, Tests, and Experiments.

(a) Definitions for the purposes of this section:

(1) Change means a modification or addition to, or removal from, the facility or procedures

that affects a design function, method of performing or controlling the function, or an evaluation

that demonstrates that intended functions will be accomplished.

(2) Departure from a method of evaluation described in the FSAR (as updated) used in

establishing the design bases or in the safety analyses means (i) changing any of the elements of

the method described in the FSAR (as updated) unless the results of the analysis are conservative

or essentially the same; or (ii) changing from a method described in the FSAR to another method

unless that method has been approved by NRC for the intended application.

(3) Facility as described in the final safety analysis report (as updated) means:

(i) The structures, systems, and components (SSC) that are described in the final

safety analysis report (FSAR) (as updated),

(ii) The design and performance requirements for such SSCs described in the FSAR

(as updated), and

(iii) The evaluations or methods of evaluation included in the FSAR (as updated)

for such SSCs which demonstrate that their intended function(s) will be

accomplished.

(4) Final Safety Analysis Report (as updated) means the Final Safety Analysis Report (or

Final Hazards Summary Report) submitted in accordance with § 50.34, as amended and

supplemented, and as updated per the requirements of § 50.71(e) or § 50.71(f), as applicable.

(5) Procedures as described in the final safety analysis report (as updated) means those

procedures that contain information described in the FSAR (as updated) such as how structures,

systems, and components are operated and controlled (including assumed operator actions and

response times).

(6) Tests or experiments not described in the final safety analysis report (as updated)

means any activity where any structure, system, or component is utilized or controlled in a manner

which is either:

(i) Outside the reference bounds of the design bases as described in the final safety

analysis report (as updated) or

(ii) Inconsistent with the analyses or descriptions in the final safety analysis report

(as updated).

(b) Applicability. This section applies to each holder of a license authorizing operation of a

production or utilization facility, including the holder of a license authorizing operation of a

nuclear power reactor that has submitted the certification of permanent cessation of operations

required under § 50.82(a)(1) or a reactor licensee whose license has been amended to allow

possession but not operation of the facility.

(c)(1) A licensee may make changes in the facility as described in the final safety analysis report

(as updated), make changes in the procedures as described in the final safety analysis report (as
1.187-A-2

updated), and conduct tests or experiments not described in the final safety analysis report (as

updated) without obtaining a license amendment pursuant to § 50.90 only if:

(i) A change to the technical specifications incorporated in the license is not

required, and

(ii) The change, test, or experiment does not meet any of the criteria in paragraph

(c)(2) of this section.

(2) A licensee shall obtain a license amendment pursuant to § 50.90 prior to implementing

a proposed change, test, or experiment if the change, test, or experiment would:

(i) Result in more than a minimal increase in the frequency of occurrence of an

accident previously evaluated in the final safety analysis report (as updated);

(ii) Result in more than a minimal increase in the likelihood of occurrence of a

malfunction of a structure, system, or component (SSC) important to safety

previously evaluated in the final safety analysis report (as updated);

(iii) Result in more than a minimal increase in the consequences of an accident

previously evaluated in the final safety analysis report (as updated);

(iv) Result in more than a minimal increase in the consequences of a malfunction of

an SSC important to safety previously evaluated in the final safety analysis report

(as updated);

(v) Create a possibility for an accident of a different type than any previously

evaluated in the final safety analysis report (as updated);

(vi) Create a possibility for a malfunction of an SSC important to safety with a

different result than any previously evaluated in the final safety analysis report (as

updated);

(vii)Result in a design basis limit for a fission product barrier as described in the

FSAR (as updated) being exceeded or altered; or

(viii) Result in a departure from a method of evaluation described in the FSAR (as

updated) used in establishing the design bases or in the safety analyses

(3) In implementing this paragraph, the FSAR (as updated) is considered to include FSAR

changes resulting from evaluations performed pursuant to this section and analyses performed

pursuant to § 50.90 since submittal of the last update of the final safety analysis report pursuant to

§ 50.71 of this part.

(4) The provisions in this section do not apply to changes to the facility or procedures when

the applicable regulations establish more specific criteria for accomplishing such changes.

(d)(1)The licensee shall maintain records of changes in the facility, of changes in procedures, and

of tests and experiments made pursuant to paragraph (c) of this section. These records must

include a written evaluation which provides the bases for the determination that the change, test or

experiment does not require a license amendment pursuant to paragraph (c)(2) of this section.

(2) The licensee shall submit, as specified in § 50.4, a report containing a brief description

of any changes, tests, and experiments, including a summary of the evaluation of each. A report

must be submitted at intervals not to exceed 24 months.

(3) The records of changes in the facility must be maintained until the termination of a

license issued pursuant to this part or the termination of a license issued pursuant to 10 CFR Part

54, whichever is later. Records of changes in procedures and records of tests and experiments

must be maintained for a period of 5 years.
VALUE/IMPACT STATEMENT

A separate Value/Impact Statement was not prepared for this regulatory guide. The

Value/Impact Statement that was prepared as part of the Regulatory Analysis for the rulemaking in

May 1999 is still applicable. Copies of the Regulatory Analysis are available for inspection or

copying for a fee in the NRC’s Public Document Room at 11555 Rockville Pike, Rockville, MD,

Washington, DC, as part of SECY-99-130, dated May 12, 1999. The PDR may be reached by

telephone at (301)415-4737 or fax at (301)415-3548.

ADAMS Accession Number of

Regulatory Guide 1.187:

ML003759710

ADAMS Accession Number of

Revision 1 of NEI 96-07:

ML003771157