This regulatory guide is being issued in draft form to involve the public in the early stages of the development of a regulatory position in this area. It has not received

final staff review or approval and does not represent an official NRC staff position.

Public comments are being solicited on this draft guide (including any implementation schedule) and its associated regulatory analysis or value/impact statement. 

Comments should be accompanied by appropriate supporting data. Written comments may be submitted to the Rulemaking, Directives, and Editing Branch, Office of

Administration, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001; emailed to NRCREP@nrc.gov; submitted through the NRC’s interactive

rulemaking Web page at http://www.nrc.gov; faxed to (301) 415-5144; or hand-delivered to Rulemaking, Directives, and Editing Branch, Office of Administration, US

NRC, 11555 Rockville Pike, Rockville, Maryland 20852. Between 7:30 a.m. and 4:15 p.m. on Federal workdays. Copies of comments received may be examined at

the NRC’s Public Document Room, 11555 Rockville Pike, Rockville, MD. Comments will be most helpful if received by 60 days from issuance.

Requests for single copies of draft or active regulatory guides (which may be reproduced) or for placement on an automatic distribution list for single copies of future

draft guides in specific divisions should be made to the U.S. Nuclear Regulatory Commission, Washington, DC 20555, Attention: Reproduction and Distribution

Services Section, or by fax to (301)415-2289; or by email to Distribution@nrc.gov. Electronic copies of this draft regulatory guide are available through the NRC’s

interactive rulemaking Web page (see above); the NRC’s public Web site under Draft Regulatory Guides in the Regulatory Guides document collection of the NRC’s

Electronic Reading Room at http://www.nrc.gov/reading-rm/doc-collections/; and the NRC’s Agencywide Documents Access and Management System (ADAMS) at

http://www.nrc.gov/reading-rm/adams.html, under Accession No. ML071440445.

U.S. NUCLEAR REGULATORY COMMISSION June 2007

OFFICE OF NUCLEAR REGULATORY RESEARCH Division 1

DRAFT REGULATORY GUIDE

Contact: Satish Aggarwal

(301) 415-6005

DRAFT REGULATORY GUIDE DG-1132

QUALIFICATION OF SAFETY-RELATED CABLES

AND FIELD SPLICES FOR NUCLEAR POWER PLANTS

A. INTRODUCTION

The regulations established by the U.S. Nuclear Regulatory Commission (NRC) in Title 10, Part

50, of the Code of Federal Regulations (10 CFR Part 50), “Domestic Licensing of Production and

Utilization Facilities,” require that structures, systems, and components that are important to safety in a

nuclear power plant must be designed to accommodate the effects of environmental conditions [i.e.,

remain functional under postulated design-basis events (DBEs)]. Toward that end, the general

requirements are contained in General Design Criteria 1, 2, 4, and 23 of Appendix A, “General Design

Criteria for Nuclear Power Plants,” to 10 CFR Part 50. Augmenting those general requirements, the

specific requirements pertaining to qualification of certain electrical equipment important to safety are

contained in 10 CFR 50.49, “Environmental Qualification of Electric Equipment Important to Safety for

Nuclear Power Plants.” In addition, Criterion III, “Design Control,” of Appendix B, “Quality Assurance

Criteria for Nuclear Power Plants,” to 10 CFR Part 50, requires that where a test program is used to

verify the adequacy of a specific design feature, it must include suitable qualification testing of a

prototype unit under the most severe DBE.

This regulatory guide describes a method that the staff of the NRC considers acceptable for

complying with the Commission’s regulations for qualification of safety-related cables and field splices

for nuclear power plants.

The NRC issues regulatory guides to describe to the public methods that the staff considers

acceptable for use in implementing specific parts of the agency’s regulations, to explain techniques that

the staff uses in evaluating specific problems or postulated accidents, and to provide guidance to

applicants. Regulatory guides are not substitutes for regulations, and compliance with regulatory guides

is not required.
DG-1132, Page 2

This regulatory guide contains information collections that are covered by the requirements of

10 CFR Part 50, and that the Office of Management and Budget (OMB) approved under OMB control

number 3150-0011. The NRC may neither conduct nor sponsor, and a person is not required to respond to,

an information collection request or requirement unless the requesting document displays a currently valid

OMB control number.

B. DISCUSSION

IEEE Std 383-2003, “IEEE Standard for Qualifying Class 1E Electric Cables and Field Splices for

Nuclear Power Generating Stations,” published on June 10, 2004 (Ref.1), was developed by the Working

Group on Cables (SC 2.4) of the Nuclear Power Engineering Committee of the Institute of Electrical and

Electronics Engineers (IEEE) and was approved by the IEEE-SA Standards Board on December 12, 2003. 

That standard provides general requirements, direction, and methods for qualifying safety-related cables,

field splices, factory splices, and factory rework for service in nuclear power plants. Categories of cables

covered are those used for power, control, and instrumentation services, including signal and

communication cables. Most importantly, IEEE Std 383-2003 requires that the safety-related cables and

field splices must meet or exceed specified performance requirements throughout their installed life and be

subjected to quality assurance programs that include, but are not limited to, design, qualification, and

production quality control.

The objectives of qualification are to ensure that safety-related cables (single, multiconductor, and

multiplex, as well as coaxial, triaxial, and twinaxial) and field splices can be demonstrated to perform their

safety functions under postulated DBEs, and that no failure mechanism exists that could lead to commoncause failures under postulated service conditions. It is the degradation over time, followed by exposure to

the environmental extremes of temperature, pressure, humidity, radiation, mechanical stress, or chemical

spray (or a combination thereof) resulting from DBEs, which presents a potential for common-cause

failures of safety-related cables and field splices. As a result, it is necessary to establish a qualified life for

cables and splices that are installed in harsh environments and must perform a safety function during and

following the DBEs.

These objectives should be accomplished using qualification methods (type testing, operating

experience, analysis as a supplement to type testing and operating experience, ongoing qualification, or

any combination thereof). However, qualification by analysis alone is not acceptable. Type testing of

sample cables or field splices is the preferred qualification method. In addition, IEEE Std 383-2003

requires documentation, in an auditable form, to demonstrate that cables and field splices would

adequately perform their safety functions.

Power cables that are routed underground should be capable of performing their function when

subjected to anticipated environmental conditions such as moisture or flooding. Also, based on recent

underground power cable failures, the staff has concluded that the field splices for medium-voltage cables

in inaccessible locations should not be permitted. In addition, power and instrumentation and control

cables for which failures could disable risk-significant equipment should have condition monitoring

programs to demonstrate that the cables can perform their safety function when needed.

C. REGULATORY POSITION

Conformance with the requirements of IEEE Std 383-2003, “IEEE Standard for Qualifying

Class 1E Electric Cables and Field Splices for Nuclear Power Generating Stations,” is a method that the
DG-1132, Page 3

NRC staff considers acceptable for use in satisfying the Commission’s regulations with respect to

qualification of safety-related cables and field splices, subject to the following exceptions:

(1) Clause 3.3, “Representative Cable,” of IEEE Std 383-2003 should be supplemented with a

description of conductor type (material, strand, and strand type) and also differentiate between

conductor shield, insulation shield, and overall static shield.

(2) Clause 4, “Principle qualification criteria,” should be supplemented as follows:

(a) The documentation should include the cable or field splice’s specification

and qualification plan.

(b) The documentation should include manufacturer’s inspection and maintenance

requirements to maintain and demonstrate continued qualification throughout its qualified

life.

(c) A condition monitoring program should also be implemented.

(3) Clause 6.1.2, “Coaxial, triaxial, and twinaxial,” should also include specimens of identical

materials and construction, and the configuration should include connections.

(4) Clause 6.2.1.1, “Conductor,” should include the stranding configuration.

(5) Clause 6.2.1.4, “Shielding,” should include percent overlap and lay for tape shields.

(6) Clause 6.2.2.6, “Identification,” should include the date of applicable manufacturing standards and

the date of manufacture.

(7) Clause 6.3, “Age conditioning,” should be supplemented to include aged cable specimen and new

splice kits; and a new splice kit combining an aged cable with a new cable.

(8) Clause 6.4.5, “Retained flexibility,” should be supplemented to include the following:

“The acceptance criteria for instrument cables should specify the

minimum acceptable insulation resistance and signal attenuation limits.”

(9) Clause 9.1, “General,” should be supplemented to include the following:

“Identification of the applicable date of manufacturing standards used in

specification, manufacture, and selection of the factory acceptance criteria

for test specimens. Documentation should also include manufacturer’s

inspection and maintenance requirements.”

(10) Power and instrumentation and control cables for which failures could disable risk-significant

equipment should have condition monitoring programs to demonstrate that the cables can perform

their safety function when needed.

IEEE Std 383-2003 references several industry codes and standards. If a referenced standard has

been separately incorporated into the regulations, licensees and applicants must comply with the standard

as set forth in the regulations. By contrast, if the NRC staff has endorsed a referenced standard in a

regulatory guide, that standard constitutes an acceptable method of meeting a regulatory requirement as

described in the regulatory guide. 
DG-1132, Page 4

D. IMPLEMENTATION

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

NRC staff’s plans for using this draft regulatory guide. No backfit is intended or approved in connection

with the issuance of this guide.

The NRC has issued this draft guide to encourage public participation in its development. Except

in cases in which an applicant or licensee proposes or has previously established an acceptable alternative

method for complying with the specified portions of the regulations, the methods to be described in the

active guide will reflect public comments and will be used in evaluating (1) submittals in connection with

applications for construction permits, design certifications, operating licenses, and combined licenses, and

(2) submittals from operating reactor licensees who voluntarily propose to initiate system modifications

involving cables and field splices.

REGULATORY ANALYSIS

1. Background

Since its issuance in February 1974, IEEE Std 383-1974, “Standard for Type Test of Class 1E

Electric Cables, Field Splices, and Connections for Nuclear Power Generating Stations,” has been used by

the nuclear industry for qualification of safety-related cables. At that time, the NRC staff had reservations

regarding IEEE Std 383-1974 and never endorsed its use. However, since that time, the staff has been

working with IEEE in revising this standard, and a revised version, IEEE Std 383-2003, “Standard for

Qualifying Class 1E Electric Cables and Field Splices for Nuclear Power Generating Stations,” was issued

in June 2004. The significant changes to IEEE Std 383-1974 include (1) removing the vertical flame test

procedure of IEEE Std 383-1974, (2) substituting a reference to IEEE Std. 1202-1991 (Ref. 2), and

(3) removing the word “connections” from the title and scope of the standard because IEEE Std 572-1985

(Ref. 3) is specific to the qualification of connections.

2. Problem

Since its issuance in February 1974, nuclear power plant licensees have typically used IEEE

Std 383-1974 for qualification of cables, subject to NRC staff review on a case-by-case basis. However,

this has been inefficient.

3. Objective

The objective of this document is to provide clear guidance on qualification of safety-related

cables and field splices. Issuing a regulatory guide is consistent with the NRC policy of evaluating the

latest versions of consensus safety standards in terms of their suitability for endorsement by regulatory

guides. This approach would also comply with the NRC’s directive to use standards developed by

consensus bodies in accordance with Public Law 104-113, “National Technology and Transfer Act of

1995” (Ref. 4).

4. Technical Approach

IEEE Std 383-1974 requires type testing as the only method of qualifying safety-related cables. 

By contrast, 10 CFR 50.49 allows alternative methods, such as qualification by past operating experience,

analysis in combination with partial type test data, and so forth. These alternative qualification methods
1 The IEEE standards are available for purchase from the IEEE Web site at

http://shop.ieee.org/ieeestore/Product.aspx?product_no=SS10041.

2 The National Technology and Transfer Act of 1995 is available electronically through the Standards.gov Web site

administered by the National Institute of Standards and Technology,

http://standards.gov/standards_gov/index.cfm?do=documents.NTTAA.

DG-1132, Page 5

are specifically included in IEEE Std 383-2003, and the vertical flame test procedure from IEEE Std 383-

1974 has been removed.

The purposes of IEEE Std 383-2003 are to provide improved guidance for cable and field splice

qualification and to clarify the existing qualification principles. In addition, this revised standard

addresses qualification of both field splices and factory-made splices, and includes the following

significant changes:

• generic and specific qualification guidance

• detailed discussion of qualification methods

• specific test sample selection criteria

• treatment of jacketed single-conductor cables

• need for overall aging program for all critical cable components

• specific requirements for thermal and radiation exposure

• detailed guidance on documentation requirements

• specific reference to high-energy line break testing

• special guidance for coaxial, twinaxial, and triaxial cables (jacket integrity, voltage, and

performance testing)

5. Conclusion

The NRC intends to issue this regulatory guide to enhance the licensing process. The staff has

concluded that the proposed action will reduce unnecessary burden on both the NRC and its licensees, and

will result in an improved and more uniform process for qualifying safety-related cables and field splices. 

Moreover, the staff sees no adverse effects associated with issuing this regulatory guide.

REFERENCES

1. IEEE Std. 383-2003, “IEEE Standard for Qualifying Class 1E Electric Cables and Field Splices for

Nuclear Power Generating Stations,” Piscataway, NJ, 1994.1

2. IEEE Std. 1202-1991, “IEEE Standard for Flame Testing of Cables for Use in Cable Tray in

Industrial and Commercial Occupancies,” Institute of Electrical and Electronics Engineers,

Piscataway, NJ, 1991.

3. IEEE Std 572-1985, “IEEE Standard for Qualification of Class 1E Connection Assemblies for

Nuclear Power Generating Stations,” Institute of Electrical and Electronics Engineers, Piscataway,

NJ, 1985.

4. National Technology and Transfer Act of 1995 (Public Law 104-113), 104th Congress of the

United States of America, Washington, DC, March 7, 1996.2