ASME Code Case Draft Regulatory Guide RG 1.84, Rev 40

U.S. NUCLEAR REGULATORY COMMISSION
	DRAFT REGULATORY GUIDE, DG 1405
	Proposed Revision 40 to Regulatory Guide RG 1.84
	Issue Date: xxx 2022 Technical Lead: Bruce Lin

DESIGN, FABRICATION, AND MATERIALS CODE CASE

ACCEPTABILITY, ASME SECTION III

1. Introduction

Purpose

This regulatory guide (RG) lists the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (BPV) Code, Section III, Division 1, “Rules for Construction of Nuclear Power Plant Components” (Ref. 1), Code Cases that the U.S. Nuclear Regulatory Commission (NRC) has approved for use as voluntary alternatives to the mandatory ASME BPV Code provisions that are incorporated by reference into Title 10 of the Code of Federal Regulations (10 CFR), Part 50, “Domestic Licensing of Production and Utilization Facilities” (Ref. 2).

Applicability

This RG applies to reactor licensees and applicants subject to 10 CFR Part 50, Section 50.55a, “Codes and standards.”

Applicable Regulations

• General Design Criterion (GDC) 1, “Quality Standards and Records,” of Appendix A, “General Design Criteria for Nuclear Power Plants,” to 10 CFR Part 50 requires, in part, that structures, systems, and components important to safety be designed, fabricated, erected, and tested to quality standards commensurate with the importance of the safety function to be performed. Where generally recognized codes and standards are used, GDC 1 requires that they be identified and evaluated to determine their applicability, adequacy, and sufficiency and be supplemented or modified as necessary to ensure a quality product in keeping with the required safety function.

• 10 CFR Part 50, Appendix A, GDC 30, “Quality of Reactor Coolant Pressure Boundary,” requires, in part, that components that are part of the reactor coolant pressure boundary be designed, fabricated, erected, and tested to the highest quality standards practical.

• 10 CFR Part 50, Appendix B, “Quality Assurance Criteria for Nuclear Power Plants and Fuel Processing Plants,” requires, in part, that measures be established for the control of special processing of materials and that proper testing be performed.

• 10 CFR 50.55a(c) requires, in part, that components of the reactor coolant pressure boundary must be designed, fabricated, erected, and tested in accordance with the requirements for the Class 1 components of ASME BPV Code, Section III, or equivalent quality standards.

• 10 CFR 52.79(a)(11) (Ref. 3) requires the final safety analysis report to include “a description of the program(s), and their implementation, necessary to ensure that the systems and components meet the requirements of the ASME Boiler and Pressure Vessel Code and the ASME Code for Operation and Maintenance of Nuclear Power Plants in accordance with 50.55a of this chapter.”

Related Guidance

• RG 1.147, “Inservice Inspection Code Case Acceptability, ASME Section XI, Division 1” (Ref. 4), lists the ASME BPV Code, Section XI, “Rules for Inservice Inspection of Nuclear Power Plant Components,” Code Cases that the NRC has approved for use as voluntary alternatives to the mandatory ASME BPV Code provisions that are incorporated into 10 CFR 50.55a.

• RG 1.192, “Operation and Maintenance Code Case Acceptability, ASME OM Code” (Ref. 5), lists the ASME Operation and Maintenance Code (OM Code) Code Cases that the NRC has approved for use as voluntary alternatives to the mandatory ASME OM Code provisions that are incorporated into 10 CFR 50.55a.

• RG 1.193, “ASME Code Cases Not Approved for Use” (Ref. 6), lists the ASME BPV Code, Section III and Section XI, Code Cases and the ASME OM Code Cases that the NRC has not approved for generic use.

• RG 1.136, “Design Limits, Loading Combinations, Materials, Construction, and Testing of Concrete Containments” (Ref. 7), endorses ASME BPV Code, Section III, Division 2, “Code for Concrete Containments” and addresses the acceptance of ASME BPV Code, Section III, Division 2 Code Cases.

• RG 1.87, Revision 2, “Acceptability of ASME Code, Section III, Division 5 High Temperature Reactors” (Ref. 8), endorses ASME BPV Code, Section III, Division 5, “High Temperature Reactors” and addresses the acceptance of ASME BPV Code, Section III, Division 5 Code Cases.

Purpose of this Regulatory Guide

The NRC incorporated this RG into 10 CFR 50.55a by reference. The RG contains new Code Cases and revisions to existing Code Cases that the staff has approved for use, as listed in Tables 1 and 2 of this guide. The RG also states the requirements that govern the use of Code Cases. Licensees may voluntarily use Code Cases approved by the NRC as an alternative to compliance with the ASME Code provisions that have been incorporated by reference into 10 CFR 50.55a. Because the status of Code Cases continually changes, the staff plans to periodically update 10 CFR 50.55a and this guide to accommodate new Code Cases and any revisions to existing Code Cases.

Paperwork Reduction Act

This RG provides voluntary guidance for implementing the mandatory information collections in 10 CFR Parts 50 and 52 that are subject to the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et. seq.). These information collections were approved by the Office of Management and Budget (OMB), under control numbers 3150-0011 and 3150-0151, respectively. Send comments regarding this information collection to the FOIA, Library, and Information Collections Branch (T6-A10M), Office of the Chief Information Officer, U.S. Nuclear Regulatory Commission, Washington, DC 20555‑0001, or by e-mail to Infocollects.Resource@nrc.gov, or to the OMB reviewer at: OMB Office of Information and Regulatory Affairs (3150–0011 and 3150-0151), Attn: Desk Officer for the Nuclear Regulatory Commission, 725 17th Street, NW, Washington, DC 20503; email: oira_submission@omb.eop.gov.

Public Protection Notification

The NRC may not conduct or sponsor, and a person is not required to respond to, a collection of information unless the document requesting or requiring the collection displays a currently valid OMB control number.

B. DISCUSSION

Reason for Revision

RG 1.84, Revision 40, includes new information reviewed by the NRC on the Section III Code Cases listed in Supplements 2 through 7 to the 2019 Edition, and Supplements 0 through 3 to the 2021 Edition of the ASME BPV Code. This revision updates and supersedes RG 1.84, Revision 39, which included information from Supplements 0 through 7 to the 2015 Edition, Supplements 0 through 7 to the 2017 Edition, and Supplements 0 and 1 to the 2019 Edition of the ASME BPV Code.

Background

Provisions of the ASME Code have been used since 1971 as one part of the framework to establish the necessary design, fabrication, construction, testing, and performance requirements for structures, systems, and components important to safety. Among other things, ASME standards committees develop improved methods for the construction and inservice inspection of ASME Class 1, 2, 3, metal containment (MC), and concrete containment (CC) nuclear power plant components. A broad spectrum of stakeholders participates in the ASME process to help ensure consideration of various interests.

ASME publishes a new edition of the BPV Code, which includes Section III, every 2 years. In 10 CFR 50.55a(a)(1)(i), the NRC references the latest edition of Section III that the agency has approved for use. ASME also publishes Code Cases quarterly. Code Cases provide alternatives that ASME developed and approved. This RG identifies the Code Cases that the NRC has determined to be acceptable alternatives to applicable parts of Section III. Under 10 CFR 50.55a(z), a licensee or applicant may request authorization to use Section III Code Cases that the NRC has not yet endorsed. In 10 CFR 50.55a(z), the NRC permits the use of alternatives to the Code requirements referenced in 10 CFR 50.55a provided that the proposed alternatives result in an acceptable level of quality and safety and their use is authorized by the Director of the Office of Nuclear Reactor Regulation.

The NRC incorporates the ASME BPV Code by reference into 10 CFR 50.55a. NRC approved Code Cases provide an acceptable voluntary alternative to the mandatory ASME Code provisions. The regulation at 10 CFR 50.55a(b)(4) provides the requirements related to the implementation of ASME Section III Code Cases. When a licensee initially applies a Code Case listed in Table 1 or 2 of this guide, it must implement the most recent version of that Code Case incorporated by reference in 10 CFR 50.55a.

ASME may annul a Code Case because its provisions have been incorporated into the Code, the application for which it was specifically developed no longer exists, or experience has shown that the design analysis or construction method is no longer required. After ASME annuls a Code Case and after the NRC amends 10 CFR 50.55a and this guide, applicants or licensees may not implement that Code Case for the first time. However, a licensee or an applicant that implemented the Code Case before its annulment may continue to use that Code Case until it voluntarily updates its Section III Code of Record. If the NRC incorporated a Code Case by reference into 10 CFR 50.55a and ASME later annulled it because experience has shown that the design analysis or construction method is no longer required, the NRC will amend 10 CFR 50.55a and this guide to remove the approval of the annulled Code Case. Licensees or applicants should not begin to implement such annulled Code Cases in advance of the rulemaking. Notwithstanding these requirements, the Commission may impose new or revised Code requirements, including implementation schedules, that it determines are consistent with 10 CFR 50.109, “Backfitting.”

A Code Case may be revised, for example, to incorporate user experience. The licensee or applicant cannot apply an older or superseded version of the Code Case for the first time. If an applicant or a licensee applied a Code Case listed in Table 1 or 2 of this guide before it was listed as superseded, it may continue to use the Code Case until it updates its Construction Code of Record (an applicant would update its application). If a Code Case is incorporated by reference into 10 CFR 50.55a and ASME later issues a revised version of the Code Case because experience has shown that the design analysis, construction method, examination method, or testing method is inadequate, the NRC will amend 10 CFR 50.55a and the relevant RG to remove the approval of the superseded Code Case. Applicants and licensees should not begin to implement such superseded Code Cases in advance of the rulemaking.

With regard to the use of any Code Case, the user is responsible for ensuring that the provisions of the Code Case do not conflict with the licensee’s commitments or regulatory requirements.

C. REGULATORY POSITION

For RG 1.84, Revision 40, the NRC reviewed the Section III Code Cases listed in Supplements 2 through 7 to the 2019 Edition, and Supplements 0 through 3 to the 2021 Edition of the ASME BPV Code.¹ RG 1.84, Revision 40 supersedes the information in Revision 39. Appendix A to this guide lists the supplements reviewed by the NRC, the editions, the supplement numbers, and the numerical listing of Section III Code Cases in each supplement. Appendix B to this guide lists all current Section III Code Cases and table where each code case is listed. The following five tables list the Code Cases addressed by this RG:

1. Table 1, “Acceptable Section III Code Cases,” lists Code Cases that are acceptable to the NRC for application in the design and construction of light‑water‑cooled nuclear power plants.

2. Table 2, “Conditionally Acceptable Section III Code Cases,” lists Code Cases that are acceptable as long as they are used with the identified conditions (i.e., the Code Case is generally acceptable; however, the NRC has determined that requirements in the Code Case, which are alternative requirements to the BPV Code, must be supplemented to provide an acceptable level of quality and safety).

3. Table 3, “Annulled Unconditionally Approved Section III Code Cases,” lists Code Cases that have been annulled by ASME.

4. Table 4, “Annulled Conditionally Acceptable Section III Code Cases,” lists Code Cases that the NRC found to be acceptable as long as the licensee used them with the identified conditions; however, they were subsequently annulled by ASME.

5. Table 5, “Section III Code Cases That Have Been Superseded by Revised Code Cases on or after July 1, 1974,” lists Code Cases that have been superseded through revision.

1. Acceptable Section III Code Cases

The NRC finds the Code Cases listed in Table 1 to be acceptable for application in the design and construction of components and their supports for water‑cooled nuclear power plants. RG 1.193 lists the ASME Code Cases that the NRC determined to be unacceptable. ASME publishes the Code Cases quarterly in supplements to each edition. To assist users, new and revised Code Cases are shaded in grey to distinguish them from those approved in previous versions of this guide. For Code Cases previously listed in this guide, the third column of Table 1 lists the dates of ASME approvals. For new or revised Code Cases, the third column of Table 1 lists the supplement and edition in which each Code Case was published (e.g., “5/17E” means Supplement 5 to the 2017 Edition of the ASME BPV Code).

Table 1. Acceptable Section III Code Cases

CODE CASE NUMBER	TABLE 1 ACCEPTABLE SECTION III CODE CASES	DATE OR SUPPLEMENT/ EDITION
N-4-13	Special Type 403 Modified Forgings or Bars, Section III, Division 1, Class 1 and CS	2/12/08
N-60-6	Material for Core Support Structures, Section III, Division I	12/6/11
N-131-1 (1759-1)	Material for Internal Pressure Retaining Items for Pressure Relief Valves, Section III, Division 1, Class 1, 2, and 3	2/3/03
N-133-3	Use of SB-148 Alloys 952 and 954, Section III, Division 1, Class 3	2/3/03
N-154-1	Projection Resistance Welding of Valve Seats, Section III, Division 1, Classes 1, 2, and 3	2/3/03
N-205	Use of Ductile Iron SA-395, Section III, Division 1, Class 3	2/25/02
N-249-17	Additional Materials for Subsection NF, Classes 1, 2, 3, and MC Supports Fabricated without Welding, Section III, Division 1	4/10/18
N-284-4	Metal Containment Shell Buckling Design Methods, Class MC, TC, and SC Construction, Section III, Divisions 1 and 3	10/8/12
N-315	Repair of Bellows, Section III, Division 1	2/3/03
N-319-3	Alternate Procedure for Evaluation of Stresses in Butt Welding Elbows in Class 1 Piping, Section III, Division 1	2/3/03
N-351-1	Use of Standard Subsize Charpy V-Notch Impact Specimens, Section III, Division 1; Section III, Division 2; Section III, Division 3	3/21E
N-369	Resistance Welding of Bellows, Section III, Division 1	5/9/03
N-373-3	Alternative PWHT Time at Temperature for P-No. 5A or P-No. 5B Group 1 Material, Classes 1, 2, and 3	10/8/04
N-405-1	Socket Welds, Section III, Division 1	2/20/04
N-452	Specialized Subcontracted Welding Process (Electron Beam Welding), Section III, Division 1	5/9/03
N-453-3	Nickel-Chromium-Molybdenum-Copper Stainless Steel (UNS N08925) for Class 2 and 3 Construction, Section III, Division 1	8/14/01
N-454-1	Nickel-Chromium-Molybdenum-Copper Stainless Steels (UNS N08925 and N08926) Wrought Fittings for Class 2 and 3 Construction, Section III, Division 1	6/17/03
N-455-1	Nickel-Chromium-Molybdenum-Copper Stainless Steels (UNS N08925 and N08926) Forged Flanges and Fittings for Class 2 and 3, Section III, Division 1	6/17/03
N-469-1	Martensitic Stainless Steel for Class 1, 2, and 3 Components, Section III, Division 1	2/3/03
N-500-4	Alternative Rules for Standard Supports for Classes 1, 2, 3 and MC, Section III, Division 1	10/14/11
N-505	Alternative Rules for the Examination of Butt Welds Used as Closure Welds for Electrical Penetration Assemblies in Containment Structures, Section III, Division 1	5/4/04
N-511	Design Temperature for Atmospheric and 0–15 psi Storage Tanks, Section III, Division 1	5/4/04
N-520-6	Alternative Rules for Renewal of Active or Expired N-Type Certificates for Plants Not in Active Construction, Section III, Division 1	12/11/12
N-525	Design Stress Intensities and Yield Strength Values for UNS N06690 with a Minimum Specified Yield Strength of 30 ksi, Class 1 Components, Section III, Division 1	7/23/02
N-539-1	UNS N08367 in Class 2 and 3 Valves, Section III, Division 1	8/16/16
N-548	Air Cooling of SA-182 Grades F304, F304L, F316, F316L Forgings Instead of Liquid Quenching After Solution Heat Treatment, Class 1, 2, and 3, Section III, Division 1	9/7/01
N-564-2	UNS J93380, Alloy CD3MWCuN, Class 2 and 3 Construction, Section III, Division 1	2/3/03
N-579	Use of Nonstandard Nuts, Class 1, 2, and 3, MC, CS Components and Supports Construction, Section III, Division 1	2/3/03
N-580-2	Use of Alloy 600 with Columbium Added, Section III, Division 1	1/4/08
N-594-1	Repairs to P-4 and P-5A Castings without Postweld Heat Treatment Class 1, 2, and 3 Construction, Section III, Division 1	10/14/11
N-607	Guidance on Implementation of NS Certificate of Accreditation, Section III, Division 1	5/4/04
N-610	Alternative Reference Stress Intensity Factor (K1R) Curve for Class Components, Section III, Division 1	5/4/04
N-620	Rules for Class 1 Type M Pumps, Section III, Division 1	5/4/04
N-621-1	Ni-Cr-Mo Alloy (UNS N06022) Welded Construction to 800°F, Section III, Division 1	10/8/04
N-625-1	Ni-Cr-Mo Alloy (UNS N06059) Welded Construction to 800°F, Section III, Division 1	2/20/04
N-631	Use of Fracture Toughness Test Data to Establish Reference Temperature for Pressure Retaining Materials Other Than Bolting for Class 1 Vessels, Section III, Division 1	7/23/02
N-635-1	Use of 22Cr-5Ni-3Mo-N (Alloy UNS S31803) Forgings, Plate, Bar, Welded and Seamless Pipe, and/or Tube, Fittings, and Fusion Welded Pipe with Addition of Filler Metal, Classes 1, 2 and 3, Section III, Division 1	2/14/03
N-636	Use of 18Cr-13Ni-3Mo (Alloy UNS S31703), 19Cr-15Ni-4Mo (Alloy UNS S31725), and 18.5Cr-15.5Ni-4.5Mo-N (Alloy UNS S31726) Forgings, Seamless Tubing, Plate, Welded Tubing, Welded and Seamless Pipe, Welded Pipe with Addition of Filler Metal and Fittings, Classes 2 and 3, Section III, Division 1	7/23/02
N-637-1	Use of 44Fe-25Ni-21Cr-Mo (Alloy UNS N08904) Plate, Bar, Fittings, Welded Pipe, and Welded Tube, Classes 2 and 3, Section III, Division 1	9/20/10
N-642	Alternative Rules for Progressive Liquid Penetrant Examination of Groove Welds In P-No. 8 Materials 3/16 in. (5 mm) Thick and Less Made by Autogenous Machine or Automatic Welding, Section III, Division 1	2/3/03
N-644-1	Weld Procedure Qualification for Procedures Exempt From PWHT in Classes 1, 2, and 3 Construction, Section III, Division 1	3/28/01
N-650	Use of SA-537, Class 2 Plate Material in Non-pressure Boundary Application Service 700°F to 850°F, Class 1 or CS, Section III, Division 1	2/20/04
N-655-2	Use of SA-738, Grade B, for Metal Containment Vessels, Class MC, Section III, Division 1	6/6/10
N-692-1	Use of Standard Welding Procedures, Section III, Division 1	5/9/16
N-698	Design Stress Intensities and Yield Strength for UNS N06690 with a Minimum Specified Yield Strength of 35 ksi (240 MPa), Class 1 Components, Section III, Division 1	11/18/03
N-699	Use of Titanium Grade 2 (UNS R50400) Tube and Bar, and Grade 1 (UNS R50250) Plate and Sheet for Class 1 Construction, Section III, Division 1	1/5/06
N-703	Use of Strain Hardened Austenitic Material at Lower Design Stress Values for Class 1 Valves, Section III, Division 1	5/4/04
N-708	Use of JIS G-4303, Grades SUS304, SUS304L, SUS316, and SUS316L, Section III, Division 1	9/21/07
N-710	Use of Zirconium Alloy UNS R60702, Bars, Forgings, Plate, Seamless and Welded Fittings, Seamless and Welding Tubing, and Seamless and Welded Pipe, for Class 3 Construction, Section III, Division 1	5/4/04
N-721-1	Alternative Rules for Linear Piping Supports, Section III, Division 1	10/20/16
N-725	Design Stress Values for UNS N06690 with Minimum Specified Yield Strength of 35 ksi (240 MPa), Classes 2 and 3 Components, Section III, Division 1	1/12/05
N-727	Dissimilar Welding Using Continuous Drive Friction Welding for Reactor Vessel CRDM/CEDM Nozzle to Flange/Adapter Welds, Classes 1, Section III, Division 1	2/24/06
N-736	Use UNS S32050 Welded and Seamless Pipe and Tubing, Forgings, and Plates Conforming to SA-249/SA-249M, SA-479/SA-479M, and SA‑240/SA‑240M, and Grade CK35MN Castings Conforming to ASTM A 743‑03 for Construction of Class 1, 2, and 3 Components, Section III, Division 1	1/5/06
N-738	NDE of Full Penetration Butt Welds in Class 2 Supports, Section III, Division 1	7/1/05
N-741	Use of 22Cr-5Ni-3Mo-N (Alloy UNS S32205 Austenitic/ferritic Duplex Stainless Steel) Forging, Plate, Welded and Seamless Pipe Tubing, and Fittings to SA-240, SA-0789, A 790-04a, SA-815, Classes 2 and 3, Section III, Division 1	10/11/05
N-746	Use of 46Fe-24Ni-21Cr-6Mo-Cu-N (UNS N08367) Bolting Materials for Class 2 and 3 Components, Section III, Division 1	1/5/06
N-756	Alternative Rules for Acceptability for Class 1 Valves, NPS (DN 25) and Smaller with Nonwelded End connections Other Than Flanges, Section III, Division 1	1/21/07
N-759-2	Alternative Rules for Determining Allowable External Pressure and Comprehensive Stress for Cylinders, Cones, Spheres, and Formed Heads, Section III, Division 1	1/4/08
N-760-2	Welding of Valve Plugs to Valve Stem Retainers, Classes 1, 2, and 3, Section III, Division 1	10/10/08
N-767	Use of 21 Cr-6Ni-9Mn (Alloy UNS S21904) Grade GXM-11 (Conforming to SA‑182/SA‑182M and SA-336/SA-336M), Grade TPXM-11 (Conforming to SA‑312/SA‑312M) and Type XM-11 (Conforming to SA-666) Material, for Class‑1 Construction, Section III, Division 1	1/4/08
N-774	Use of 13Cr-4Ni (Alloy UNS S41500) Grade F6NM Forgings Weighing in Excess of 10,000 lb (4,540 kg) and Otherwise Conforming to the Requirements of SA‑336/SA‑336M for Class 1, 2, and 3 Construction, Section III, Division 1	9/3/08
N-777	Calibration of Cv Impact Test Machines, Section III, Divisions 1, 2, and 3	10/10/08
N-782	Use of Editions, Addenda, and Cases, Section III, Division 1	1/30/09
N-785	Use of SA-479/SA-479M, UNS S41500 for Class 1 Welded Construction, Section III, Division 1	10/12/09
N-801-3	Rules for Repair of N-Stamped Class 1, 2, and 3 Components, Section III, Division 1	5/11/17
N-815	Use of SA-358/SA-358M Grades Fabricated as Class 3 or Class 4 Welded Pipe, Class CS Core Support Construction, Section III, Division 1	12/6/11
N-816	Use of Temper Bead Weld Repair Rules Adopted in 2010 Edition and Earlier Editions, Section III, Division 1	12/6/11
N-817	Use of Die Forgings, SB-247, UNS A96061, Class T6, with Thickness ≤ 4.000 in. Material, Class 2 Construction (1992 Edition or Later), Section III, Division 1	12/6/11
N-819	Use of Die Forgings, SB-247, UNS A96061, Class T6, with Thickness ≤ 4.000 in. Material, Class 2 Construction (1989 Edition with the 1991 Addenda or Earlier), Section III, Division 1	12/6/11
N-822-4	Application of the ASME Certification Mark, Section III, Divisions 1, 2, 3, and 5	8/2/16
N-834	ASTM A988/A988M-11 UNS S31603, Subsection NB, Class 1 Components, Section III, Division 1	10/22/13
N-836	Heat Exchanger Tube Mechanical Plugging, Class 1, Section III, Division 1	10/22/13
N-841	Exemptions to Mandatory Post Weld Heat Treatment (PWHT) of SA‑738 Grade B for Class MC Applications, Section III, Division 1	1/6/14
N-844	Alternatives to the Requirements of NB-4250(c) Section III, Division 1	2/9/14
N-855	SB-148 C95800 Valves for Class 3 Construction, Section III, Division 1	7/8/15
N-856	SA-494 Grade CW-12MW (UNS N30002) Nickel Alloy Castings for Construction of NPS 2½ and Smaller Flanged Valves for Class 3 Construction, Section III, Division 1	7/16/15
N-859	Construction of ASME B16.9 Wrought Buttwelding Fittings and ASME B16.11 Forged Fittings Made From SB-366 UNS N04400 Material for Section III, Class 3 Construction, Section III, Division 1	1/20/16
N-863-1	Postweld Heat Treatment (PWHT) of Valve Seal Welds for P4 and P5A Materials, Section III, Division 1	2/16/17
N-866	Alternative Materials for Construction of Section III, Class 2 Vessels, Section III, Division 1	11/14/16
N-870-1	Rules for the Elimination of External Surface Defects on Class 1, 2, and 3 Piping, Pumps, or Valves After Component Stamping and Prior to Completion of the N-3 Data Report, Section III, Division 1	11/2/17
N-879	Use of Micro-Alloyed Carbon Steel Bar in Patented Mechanical Joints and Fittings, Classes 1, 2, and 3, Section III, Division 1	5/10/17
N-884	Procedure to Determine Strain Rate for Use With the Environmental Fatigue Design Curve Method and the Environmental Fatigue Correction Factor, Fen, Method as Part of an Environmental Fatigue Evaluation for Components Analyzed per the NB-3200 Rules, Section III, Division 1	10/23/18
N-887	Alternatives to the Requirements of NB-4424.2(a), Figure NB-4250-2, and Figure NB-4250-3, Section III, Division 1	5/2/18
N-891	Alternative Requirements to Appendix XXVI, XXVI-2400, XXVI-4130, and XXVI-4131 for Inspection and Repair of Indentations for Polyethylene Pipe and Piping Components, Section III, Division 1	12/17/18
N-893	Use of Alloy Steel Bar and Mechanical Tubing in Class 2 and 3 Patented Mechanical Joints and Fittings, Section III, Division 1	4/19E
N-900	Alternative Rules for Level D Service Limits of Class 1, 2, and 3 Piping Systems, Section III, Division 1	3/19E
N-901	Use of ASME SA-494 Grade M35-1 for Line Valve Bodies and Bonnets, and Bodies, Bonnets, and Yokes of Pressure Relief Valves for Class 2 and 3 Construction, Section III, Division 1	4/19E
N-902	Thickness and Gradient Factors for Piping Fatigue Analyses, Section III, Division 1	5/19E
N-904	Alternative Rules for Simplified Elastic–Plastic Analysis, Section III, Division 1	6/19E
N-905	Alternate Design Fatigue Curves to Those Given in For Section III Appendices, Mandatory Appendix I, Figures I-9.1 and I-9.1M, Section III, Division 1	6/19E
N-908	Use of Ferritic/Austenitic Wrought WPS32750/CRS32750 Fittings of Seamless or Welded Construction Conforming to SA-815, Class 3, Section III, Division 1	7/19E
N-910	Use of 25Cr-7Ni-4Mo-N (Alloy UNS S32750 Austenitic/Ferritic Duplex Stainless Steel) Forgings, Plate, and Welded and Seamless Pipe and Tubing Conforming to SA-182, SA-240, SA-789, or SA-790, Section III, Division 1	7/19E
N-919	Alternative Fatigue Evaluation Method to Consider Environmental Effects on Class 1 Components Section III, Division 1	2/21E
N-920	Alternative Fatigue Design Curves for Ferritic Steels With Ultimate Tensile Strengths (UTS) ≤ 80 ksi (552 MPa) and Austenitic Steels, Section III, Division 1	2/21E

2. Conditionally Acceptable Section III Code Cases

The NRC finds the Code Cases listed in Table 2 to be acceptable for application in the design and construction of components and their supports for water-cooled nuclear power plants within the limitations indicated by the NRC. Unless otherwise stated, limitations indicated by the NRC are in addition to the conditions specified in the Code Case. ASME publishes Code Cases quarterly in supplements to each edition. To assist users, new and revised Code Cases are shaded in grey to distinguish them from those approved in previous versions of this guide. For Code Cases previously listed in this guide, the third column of Table 1 lists the date of ASME approval. For new or revised Code Cases, the third column of Table 1 lists the supplement and edition in which each Code Case was published (e.g., “5/17E” means Supplement 5 to the 2017 Edition of the ASME BPV Code).

Table 2. Conditionally Acceptable Section III Code Cases

CODE CASE NUMBER	TABLE 2 CONDITIONALLY ACCEPTABLE SECTION III CODE CASES TITLE/CONDITION	DATE OR SUPPLEMENT/ EDITION
N-62-7	Internal and External Valve Items, Section III, Division 1, Classes 1, 2, and 3 The Code requires that Class 1 and Class 2 valve manufacturers to meet the provisions of Section III, Article NCA‑4000, “Quality Assurance.” Class 3 valve manufacturers must also meet the provisions of Article NCA‑4000 because all Code Class valve items are subject to the licensee’s 10 CFR Part 50, Appendix B, approved quality assurance program.	2/3/03
N-71-21	Additional Materials for Subsection NF, Class 1, 2, 3, and MC Supports Fabricated by Welding, Section III, Division 1 (1) The maximum measured ultimate tensile strength (UTS) of the component support material must not exceed 170 ksi because of the susceptibility of high‑strength materials to brittleness and stress‑corrosion cracking. (2) In the last sentence of Paragraph 5.2 of Code Case N‑71-21, the evidence presented to and accepted by the Authorized Inspector concerning exposure of electrodes for a longer period of time must be consistent with Paragraph 5.3.2.3, “Alternative Atmosphere Exposure Time Periods Established by Test,” of the AWS D1.1 Code. (3) Paragraph 16.2.2 of Code Case N-71-21 is replaced with the following: “When not exempted by 16.2.1 above, the post weld heat treatment must be performed in accordance with NF‑4622 except that ASTM A-710 Grade A Material must be at least 1000°F (540°C) and must not exceed 1150°F (620°C) for Class 1 and 2 material and 1175°F (640°C) for Class 3 material.” (4) The new holding time at temperature for weld thickness (nominal) must be 30 minutes for welds 0.5 inch or less; 1 hour per inch of thickness for welds over 0.5 inch to 5 inches; and for thicknesses over 5 inches, 5 hours plus 15 minutes for each additional inch over 5 inches. (5) The fracture toughness requirements as listed in this Code Case apply only to piping supports and not to Class 1, 2 and 3 component supports. (6) When welding Pnumber materials listed in the Code Case, the corresponding Snumber welding requirements apply.	0/21E
N-155-3	Fiberglass Reinforced Thermosetting Resin Pipe, Section III, Division 1 The design temperature for spray pond piping must be 100°C (212°F). The allowable design stress must be the value obtained from the minimum hydrostatic design basis in Table 3611-1 of Code Case N‑155‑2 (Procedure A or B) or the value determined as one‑sixth of the stress obtained from a short-time burst test for the pipe being qualified, whichever is lower. The short-time burst strength must be determined by bursting the pipe (ASTM D‑1599‑74) using free‑end mounting after it has been exposed to 1x105 pressure cycles from atmospheric to design pressure. The value of “K” in Equation 9 of Paragraph 3652 must be limited to 1.2 unless it is demonstrated that, with the use of a large value of K1, the functional capability of the system will not be impaired during upset and emergency conditions. RTR piping must be uninsulated or uncovered and installed under conditions that make it readily accessible for inspection. Preoperational and inservice inspections must be as follows: During the preoperational testing period, tests must be made to verify that the piping is free of vibration induced by weather conditions or water flow that could fatigue the piping prematurely. Fiberglass-reinforced piping components must be inspected in accordance with ASME Code, Section XI, for Code Class 3 components. In addition, all pipe supports must be inspected. Inspection frequency for piping must be increased to once annually if an exterior weather‑resistant coating is not provided.	2/11/16
N-570-3	Alternative Rules for Linear Piping and Linear Standard Supports for Classes 1, 2, 3, and MC, Section III, Division 1 This Code Case shall not be used with the Load and Resistance Factor Design method of ANSI/AISC N-690-2018.	0/21E
N-757-1	Alternative Rules for Acceptability for Class 2 and 3 Valves (DN 25) and Smaller with Welded and Nonwelded End Connections Other Than Flanges, Section III, Division 1 The design provisions of ASME Section III, Division 1, Appendix XIII, shall not be used for Class 3 valves.	9/21/07
N-779	Alternative Rules for Simplified Elastic-Plastic Analysis Class 1, Section III, Division 1 Acceptable for use with code editions Summer 1979 addenda and later.	1/26/09
N-852	Application of the ASME NPT Stamp, Section III, Divisions 1, 2, 3, and 5 Licensees may use the NPT Code Symbol Stamp with the letters arranged horizontally as specified in ASME BPV Code Case N–852 for the service life of a component that had the NPT Code Symbol Stamp applied during the time period from January 1, 2005 through December 31, 2015.	2/9/15
N-883	Construction of Items Prior to the Establishment of a Section III, Division 1 Owner, Section III, Division 1 This Code Case may only be used for the construction of items by a holder of a construction permit, operating license, or combined license under 10 CFR Part 50 or Part 52. This Code Case may not be used by a holder of a manufacturing license or standard design approval or by a design certification applicant.	1/29/18
N-886	Use of Polyethylene Pipe for Class 3, Section III, Division 1 For above ground applications, licensees must ensure the plant fire protection program addresses any HDPE consistent with the requirements of 10 CFR 50.48.	5/2/18

3. Annulled Unconditionally Approved Section III Code Cases

The NRC had previously approved the Code Cases listed in Table 3 unconditionally, but they have since been annulled by ASME. To assist users, new annulled Code Cases are shaded in grey to distinguish them from those listed in previous versions of this guide.

Table 3. Annulled Unconditionally Approved Section III Code Cases

CODE CASE NUMBER	TABLE 3 ANNULLED UNCONDITIONALLY APPROVED SECTION III CODE CASES	ANNULMENT DATE
N-1-7 (1332-7)	Requirements for Steel Forgings, Section III, Division 1	7/1/82
N-2 (1334-3)	Requirements for Corrosion-Resisting Steel Bars and Shapes, Section III	1/1/82
N-3-10 (1335-10)	Requirements for Bolting Materials, Section III	9/16/84
N-5-1	Nickel Chromium Age Hardenable Alloys (Alloy X750), Section III, Division 1, Classes 1, 2, 3, MC, and CS	12/13/85
N-6 (1345-2)	Requirements for Nickel-Molybdenum-Chromium-Iron Alloys, Section III	3/1/79
N-7-1	High Yield Strength Steel, Class 1, Section III, Division 1	2/22/05
N-9-4 (1395-4)	SA-508, Class 2 Forgings with Modified Manganese Content, Section III	7/1/82
N-10 (1407-3)	Time of Examination for Classes, 1, 2, and 3, Section III Vessels	9/17/87
N-15 (1456-2)	Substitution of Ultrasonic Examination for Progressive Penetrant or Magnetic Particle Examination of Partial Penetration and Oblique Nozzle Attachment Welds, Section III	3/1/79
N-17 (1474-1)	Integrally Finned Tubes for Section III	1/21/91
N-20-4	SB-163, Cold Worked UNS N08800; and SB-163 UNS N06600, UNS N06690, and UNS N08800 to Supplementary Requirements S2 of SB-163, Section III, Division 1, Class 1	9/18/01
N-22 (1498-1)	SA-508-Class 2 and 3, Minimum Tempering Temperature, Section III	7/1/82
N-24 (1516-2)	Welding of Seats or Minor Internal Permanent Attachments in Valves for Section III Applications	1/1/80
N-30-1 (1539-1)	Metal Bellows and Metal Diaphragm Stem Sealed Valves, Section III, Division 1, Classes 1, 2, and 3	1/1/81
N-32-3 (1541-3)	Hydrostatic Testing of Embedded Class 2 and Class 3 Piping for Section III, Division 1 Construction	7/1/79
N-33 (1542-1)	Type 403 Forgings or Bars for Bolting Material, Section III	1/21/85
N-35-1 (1552-1)	Design by Analysis of Section III, Class 1 Valves	7/1/79
N-37-3 (1557-3)	Steel Products Refined by Secondary Remelting, Section III and VIII, Division 1 and 2	7/1/82
N-41 (1571)	Additional Material for SA-234 Carbon Steel Fittings, Section III	1/21/85
N-43 (1578)	SB-167 Nickel-Chromium-Iron (Alloy 600) Pipe or Tube, Section III	7/1/82
N-46 (1588)	Electro-Etching of Section III Code Symbols	3/19/82
N-48-2	Fabrication and Installation of Elevated Temperature Components, Section III, Division 1	7/1/96
N-49-4	Examination of Elevated Temperature Nuclear Components, Section III, Class 1	7/1/96
N-50-1	Testing of Elevated Temperature Components, Section III, Division 1, Class 1	7/1/96
N-51-2	Protection against Overpressure of Elevated Temperature Components, Section III, Division 1, Class 1	7/1/96
N-55-1 (1609)	Inertia and Continuous Drive Friction Welding, Section III, Division 1	4/5/87
N-56 (1612)	Use of Type 308 Stainless Steel Rod and Bar for Section III, Class 1, 2, 3, and CS Construction	7/1/78
N-61 (1620)	Stress Category for Partial Penetration Welded Penetrations, Section III, Class Construction	1/8/82
N-65-1 (1626-1)	Normalized and Tempered 1-1/4 Cr Low Alloy Steel Forgings, Section I and III	1/21/85
N-66-1 (1630-1)	External Pressure Charts for High Yield Strength Carbon Steels and Low Alloy Steels (Yield Strength above 38 ksi to 60 ksi Inclusive) For Section III, Class 1, 2, 3, and MC	12/5/87
N-68 (1634-2)	Use of SB-359 for Section III, Division, 1, Class 3 Construction	7/1/78
N-77 (1660)	Overpressure Protection under Emergency Operating Conditions for Section III, Class 1	7/1/77
N-81 (1665)	Pressure-Temperature Ratings for Class 1 Valves Made from 5 Cr‑1/2 Mo, Section III	7/1/78
N-82 (1677)	Clarification of Flange Design Loads, Section III, Class 1, 2, and 3	3/1/79
N-84 (1681-1)	Organizations Accepting Overall Responsibility for Section III Construction	3/1/79
N-90 (1692)	Rules for Design of Welded Class 1 Pumps	7/1/78
N-94 (1700)	Determination of Capacities of Liquid Relief Valves, Section III, Division 1, Class 1, 2, and 3	3/19/82
N-95-2 (1701-2)	Determination of Capacities of Vacuum Relief Valves, Section III, Division 1, Classes 2, 3, and MC and Division 2 Concrete Containments	7/9/82
N-96-1 (1702-1)	Flanged Valves Larger than 24 Inches for Section III, Division 1, Class 1, 2, and 3 Construction	1/1/80
N-101 (1712)	Nameplates and Stamping for Section III, Division 1, Class 1, 2, 3 and MC Construction as Referenced in NA‑8300	3/1/79
N-102-2	Postweld Heat Treatment of P-1 Material, Section III, Class MC	6/30/84
N-107-1 (1722-1)	Vacuum, Carbon Deoxidized SA-508 Forgings, Section III, Division 1	1/8/82
N-108 (1724)	Deviation from the Specified Silicon Ranges in ASME Material Specifications, Section III, Division 1, and VIII, Division 1 and 2	7/1/78
N-109 (1726)	Refinement of Low Alloy Steel Heat Affected Zone under Overlay Cladding, Section III, Division 1, Class 1 Components	3/1/79
N-111 (1729)	Minimum Edge Distance-Bolting for Section III, Division 1, Class 1, 2, and 3 and MC Construction of Component Supports	3/1/79
N-114 (1732)	Hardsurfaced Valves with Inlet Connections Less Than 2‑in. Nominal Pipe Size for Section III, Division 1, Class 1 and 2 Construction	1/1/79
N-115 (1733)	Evaluation of Safe Shut Down Earthquake Loadings for Section III, Division 1, Class MC Containment Vessels	1/1/78
N-119-6	Pump Internal Items, Section III, Division 1, Class 1, 2, and 3	3/14/94
N-121 (1744)	Carbon Steel Pipe Flanges Larger than 24 in., Section III, Division 1, Class 2 and 3 Construction	3/1/79
N-122-2	Procedure for Evaluation of the Design of Rectangular Cross Section Attachments on Class 1 Piping, Section III, Division 1	8/20/09
N-123 (1746)	Leak Testing of Seal Welds, Section III, Division 1, Class 1, 2, and 3 Construction	3/1/79
N-124 (1747)	Requirements for Martensitic Stainless Forgings with 13% Chromium and 4% Nickel, Section III, Division 1	7/13/87
N-125 (1748)	Low Carbon Austenitic Stainless Steel Pipe Welded with Filler Metal, Section III, Division 1, Construction	7/1/78
N-126 (1754)	Hard Surfacing by the Spray-Fuse Method, Section III, Class 1, 2, and 3 Construction	7/1/88
N-127 (1755-1)	Alternative Rules for Examination of Welds in Piping, Section III, Class 1 and 2 Construction	2/20/92
N-139	Testing of Electroslag Wire and Flux for Class 1, 2, 3, MC, and CS Construction, Section III, Division 1	1/1/79
N-140 (1772)	Use of SA-453 Bolts in Service below 800°F without Stress Rupture Tests, Section III, Division 1	12/31/85
N-142-1 (1774-1)	Minimum Wall Thickness for Class 2 and 3 Valves, Section III, Division 1	1/1/80
N-147 (1781)	Use of Modified SA-487 Grade CA6NM, Section III, Division 1, Class 1, 2, 3, MC, or CS	7/1/78
N-148 (1782)	Use of Copper-Nickel Alloy 962 for Castings, Section III, Division 1, Class 3 Construction	6/30/83
N-156 (1793)	Structural Steel Rolled Shapes, Section III, Division I, Class 2, 3, and MC	2/14/86
N-157 (1794)	Use of Seamless Al-Br, Alloy CDA 614 Pipe, Section III, Division 1, Class 3	1/7/83
N-158 (1795)	Examination of Weld Repairs in Forgings, Section III, Division 1, Class 1, 2, 3, MC, and CS	7/1/78
N-159 (1796)	Body Neck Thickness Determination for Valves with Inlet Connections 4‑Inch Nominal Pipe Size and Smaller, Section III, Division 1, Class 1, 2, and 3	7/1/78
N-160-1	Finned Tubing for Construction, Section III, Division 1	10/14/11
N-174 (1812)	Size of Fillet Welds for Socket Welding of Piping, Section III, Division 1	1/1/81
N-176-1 (1819-1)	Use of Type XM-19 for Construction, Section III, Division 1, Class 1, 2, and 3	8/25/83
N-177 (1820)	Alternative Ultrasonic Examination Technique, Section III, Division 1	1/1/84
N-178	Use of ASTM B271, CDA 954, Alloy 9C for Class 3 Construction, Section III, Division 1	1/1/80
N-179	Openings in Valves for Section III, Division 1, Class 1, 2 and 3 Construction	7/11/80
N-180	Examination of Springs for Class 1 Component Standards Supports, Section III, Division 1	7/1/78
N-181	Steel Castings Refined by the Argon Decarburization Process, Section III, Division 1, Construction	7/11/80
N-182	Alternate Rules for Procedure Qualification Base Material Orientation, Section III, Division 1, Class 2 and 3 Construction	7/1/81
N-183	Use of Modified SA-182 Grade F22 for Section III, Division 1, Class 1, 2 and 3 Construction	1/1/80
N-184	Roll Threading of SA-453 Bolting for Section III, Division 1, Class 1, 2, 3, or CS Construction	7/1/79
N-188-1	Use of Welded Ni-Fe-Cr-Mo-Cu (Alloy 825) and Ni-Cr-Mo-Cb (Alloy 625) Tubing, Section III, Division 1, Class 2 and 3	8/14/96
N-189	Primary Membrane Plus Primary Bending Stress Intensity Limits for Other Than Solid Rectangular Sections for Section III, Division 1, Class MC Construction	7/1/79
N-190	Use of SA-455 for Class 3 Components, Section III, Division 1	7/1/78
N-192-3	Use of Braided Flexible Connectors, Section III, Division 1, Class 2 and 3	1/7/15
N-193	Use of SB-61 and SB-62 Bronze for Section III, Division 1, Class 3 Flange and Socket Weld End Valves	11/21/80
N-196-1	Exemption from the Shakedown Requirements When Plastic Analysis Is Performed for Section III, Division 1, Class 1 and CS Construction	7/1/92
N-204	Use of Modified SA-508, Class 3, and SA-541, Class 3 for Section III, Division 1, Class 1, 2, and 3 Components	1/1/81
N-206	Use of ASTM B151-75 Copper-Nickel Alloy 706 Rod and Bar for Section III, Division 1, Class 3 Construction	6/30/83
N-207-1	Use of Modified SA-479 Type XM-19 for Section III, Division 1, Class 1, 2, 3, or CS Construction	1/21/85
N-212 (1693)	Welding Procedure Qualification of Dissimilar Metal Welds When “Buttering” with Alloy Weld Metal and Heat Treatment May Be Involved, Section III, Division 1, and Section IX	1/1/81
N-214-2	Use of SA-351 Grade CN7M, for Valves, Section III, Division 1	12/31/83
N-215	Integrally Finned Titanium Tubes, Section III, Division 1, Class 3 Construction	5/15/81
N-217-1	Postweld Heat Treatment of Weld Deposit Cladding on Classes 1, 2, 3, MC, and CS Items, Section III, Division 1	2/23/87
N-220	Code Effective Date for Component Supports, Section III, Division 1	7/13/81
N-223	Requirements for Stainless Steel Precipitation Hardening, Section III, Division 1, Class MC	11/20/81
N-224-1	Use of ASTM A500 Grade B and ASTM A501 Structural Tubing for Welded Attachments for Section III, Class 2, 3, and MC	4/5/90
N-225	Certification and Identification of Material for Component Supports, Section III, Division 1	1/1/81
N-226	Temporary Attachment of Thermocouples, Section III, Division 1, Class 1, 2 and 3 Component Supports	1/1/80
N-227	Examination of Repair Welds, Section III, Class 2 and 3 Tanks	7/9/82
N-228	Alternate Rules for Sequence of Completion of Code Data Report Forms and Stamping for Section III, Class 1, 2, 3, and MC Construction	3/19/82
N-229	Alternate Rules for Fabrication Welding SB-148 Alloy CDA 954 for Section III, Division 1, Class 3 Construction	1/21/88
N-231	Alternate Methods for Leak Detection in the Attachment Welds of Leak Chase Channels, Section III, Division 2, Class CC	7/1/92
N-233	Alternate Rules for PWHT of P-No. 6, Group 4 Material for Section III, Division 1, Class 3 Construction	9/17/87
N-237-2	Hydrostatic Testing of Internal Piping, Section III, Division 1, Classes 2 and 3	7/1/88
N-240	Hydrostatic Testing of Open Ended Piping, Section III, Division 1	7/1/97
N-241	Hydrostatic Testing of Piping, Section III, Division 1	7/1/97
N-243	Boundaries within Castings Used for Core Support Structures, Section III, Division 1, Class CS	10/14/11
N-245	Use of ASTM B61-76 and B62-76 Copper Alloy Castings for Section III, Division 1, Class 3 Construction	7/17/85
N-246-2	SB-169 Alloy C61400, Section III, Division 1, Class 3 Construction	7/27/95
N-247	Certified Design Report Summary for Component Standard Supports, Section III, Division 1, Class 1, 2, 3 and MC	4/30/93
N-248	Alternative Reference Radiographs, Section III, Division 1, Classes 1, 2, 3, MC, and CS Construction	7/1/80
N-259	Ni-Cu-Al Bolting Material SB 164 Modified, Section III, Division 1, Class 3	1/1/84
N-261	Weld Procedure Qualification for Materials with Impact Requirements for Section III, Division 1, Class 3 Construction	12/13/82
N-262	Electric Resistance Spot Welding for Structural Use in Component Supports, Section III, Division 1	7/27/91
N-265-1	Modified SA-487 Castings, Section III, Division 1, Class 1	8/14/97
N-267	Double-Wall Radiography, Section III, Division 1, Class 1 and 2	7/1/81
N-271	Simplified Method for Analyzing Flat Face Flanges with Metal to Metal Contact outside the Bolt Circle for Section III, Class 2, 3, and MC Construction	2/14/86
N-272	Compiling Data Report Forms, Section III, Division 1	1/1/82
N-276	Welding of SA-358 Pipe, Section III, Division 1	2/14/86
N-277	Use of Type XM-19 Austenitic Stainless Steel for Section III, Division 1, Class MC Construction	9/17/80
N-280	Alternate Rules for Examination of Welds in Section III, Class 3 Storage Tanks	7/1/81
N-281	Welding Operator Performance Qualification, Section III, Division 1	7/1/81
N-282	Nameplates for Valves, Section III, Division 1, Class 1, 2, and 3 Construction	7/30/89
N-294	SB-148 Alloys 952 and 954, and SB-62 Alloy 836 Fittings, Section III, Division 1, Class 2	7/27/95
N-295	NCA-1140, Materials, Section III, Division 1	6/30/82
N-296	Welding Material, Section III, Division 1 Construction	12/1/83
N-298	Examination of Component Supports, Section III, Division 1, Class 1, 2, 3, and MC	12/1/83
N-299-1	Use of Nickel-Chromium-Molybdenum-Columbium Alloy 625 Forgings, Section III, Division 1, Class 2 and Class 3 Components	2/23/87
N-300	Pressure-Temperature Ratings, Hydrostatic Tests, and Minimum Wall Thickness of Valves, Section III, Division 1, Class 1	12/1/83
N-302	Tack Welding, Section III, Division 1, Construction	11/28/83
N-304-4	Use of 20Cr-25Ni-6Mo (Alloy UNS N08366) Plate, Sheet, Strip, and Welded Pipe, Class 2 and 3, Section III, Division 1	1/1/03
N-309-1	Identification of Materials for Component Supports, Section III, Division 1	7/1/95
N-313	Alternative Rules for Half-Coupling Branch Connections, Section III, Division 1, Class 2	7/1/96
N-316	Alternative Rules for Fillet Weld Dimensions for Socket Welding Fittings, Section III, Division 1, Class 1, 2, and 3	8/14/93
N-317	ASTM A276 Bar, Section III, Division 1	7/1/82
N-318-5	Procedure for Evaluation of the Design of Rectangular Cross Section Attachments on Class 2 or 3 Piping, Section III, Division 1	8/20/09
N-320	Alternate PWHT for SA-487, Grade CA6NM, Section III, Division 1	12/31/83
N-321-1	Use of Modified SA-249, Grade TP 304, Section III, Division 1, Class 1	12/85/88
N-324	Qualification of Authorized Nuclear Inspector Supervisor (Concrete) and Authorized Nuclear Inspector (Concrete), Section III, Division 2, Classes CB and CC	7/27/95
N-328	Thermit Brazing or Welding of Nonstructural Attachments, Section III, Division 1	9/17/87
N-329	Examination of Bar Material, Section III, Division 1, Class 1	10/14/11
N-336	Examination of Welds Inaccessible during Pressure Test, Section III, Division 1, Class MC	6/30/83
N-337-1	Use of ASTM B 525-70 Grade II, Type II, Sintered Austenitic Stainless Steel for Classes 2, 3, and MC Component Standard Supports, Section III, Division 1	3/14/94
N-339	Examination of Ends of Fillet Welds, Section III, Division 1, Classes 1, 2, and MC	9/17/84
N-341	Certification of Level III NDE Examiner, Section III, Divisions 1 and 2	7/1/88
N-342	Use of SA-249 and SA-312 Type 317 Stainless Steel, Section III, Division 1, Classes 1, 2, and 3	4/2/85
N-345-1	Attachment of AMS 5382 Alloy 31 Seat Rings by Friction Welding, Section III, Division 1, Classes 1, 2, and 3	3/28/01
N-346	Explosive Welding, Section III, Division 1	6/30/86
N-347	Continuous Electric Resistance Seam Welding of P-No. 8 Materials for Component Supports, Section III, Division 1	12/13/85
N-349	Pressure Testing Piping Systems, Section III, Division 1, Classes 2 and 3	12/13/85
N-352-1	Use of SA-638 Grade 660 Forgings and Bars below 700°F without Stress Rupture Tests, Section III, Division 1	6/30/86
N-353	Marking of SA-354 Grade BD Bolting, Section III, Division 1	9/5/88
N-354-1	Subcontracted Service, Section III, Division 2	8/14/94
N-355	Calibration Block for Angle Beam Ultrasonic Examination of Large Fittings in Accordance with Appendix III-3410	8/9/96
N-357	Certification of Material for Component Supports, Section III, Division 1, Subsection NF	7/1/88
N-359	Weld Connection for Coaxial Cylinders, Section III, Division 1, Class 1	12/31/84
N-362-2	Pressure Testing of Containment Items, Section III, Division 1, Classes 1, 2, and MC	7/1/88
N-367	SA-372 Type V, Grade 1, Class B, Section III, Division 1	2/19/89
N-368	Pressure Testing of Pump Discharge Piping, Section III, Division 1, Classes 2 and 3	7/1/95
N-370-2	Modified SA-705 Type XM-13 Forgings, Section III, Division 1	8/14/97
N-371-1	12Cr-1W-1Mo-1/4V Martensitic Stainless Steel Valve Internals, Section III, Division 1	7/18/88
N-372	SB-163 Ni-Fe-Cr-Mo-Cu Alloy 825 (UNS N08825) Tubing, Section III, Division 1	12/31/83
N-376	Pressure Testing of Embedded Class 2 and 3 Piping, Section III, Division 1	7/30/86
N-377	Effective Throat Thickness of Partial Penetration Groove Welds, Section III, Division 1, Classes 1, 2, and 3	12/31/83
N-378	Examination of Piping Support Material, Section III, Division 1, Class 1	10/28/86
N-379-1	Bimetallic Tubing, Section III, Division 1, Class 1	7/18/91
N-384-1	Use of Prepackaged General Purpose Cement Grouts, Epoxy Grouts, and Epoxy Bonding, Section III, Division 2, Class CC	7/27/91
N-387	Certification of Level III NDE Examiner, Section III, Division 2	9/18/01
N-388	Component Support Bolting, Section III, Division 1, Classes 2, 3, and MC	2/23/87
N-391-2	Procedure for Evaluation of the Design of Hollow Circular Cross Section Welded Attachments on Class 1 Piping, Section III, Division 1	5/4/04
N-392-3	Procedure for Evaluation of the Design of Hollow Circular Cross Section Welded Attachments on Classes 2 and 3 Piping, Section III, Division 1	5/4/04
N-393	Repair Welding Structural Steel Bolted Shapes and Plates for Component Supports, Section III, Division 1	7/27/95
N-394	Restricting Lift to Achieve Reduced Relieving Capacities of Full Lift, Nozzle Type, and Flat Seated Safety and Safety Relief Valves for Compressible Fluid Applications, Section III, Division 1, Classes 2 and 3	3/2/01
N-395	Laser Welding, Section III, Division 1	9/18/01
N-403	Reassembly of Subsection NF Component and Piping Supports, Section III, Division 1	7/1/95
N-410	Certified Relieving Capacities of Pressure Relief Valves Having Set Pressure of 3 psig up to but Not Including 15 psig Installed for Overpressure Protection of Compressible Fluid Systems, Section III, Division 1, Classes 2 and 3	3/14/00
N-412	Alternative Rules for Witnessing the Piping System Pressure Tests of Classes 1, 2, and 3 Piping Systems, Section III, Division 1	4/15/91
N-413	Minimum Size of Fillet Welds for Subsection NF Linear Type Supports, Section III, Division 1	2/14/88
N-414	Tack Welds for Class 1, 2, 3 and MC Components and Piping Supports	2/20/92
N-418-1	Use of Seamless Ni-Fe-Cr-Mo-Cu Low Carbon (UNS N08028 and UNS N08904) Tubing, Section III, Division 1, Classes 2 and 3	7/27/95
N-420	Linear Energy Absorbing Supports for Subsection NF, Classes 1, 2, and 3 Construction	1/1/99
N-421	Brazing Using a Radiant Energy Source, Section III, Division 1	6/30/86
N-433	Non-Threaded Fasteners for Section III, Division 1, Class 1, 2, and 3 Components and Piping Supports	12/16/95
N-438-4	UNS N08367 Material, Section III, Division 1, Class 2 and 3 Construction	7/1/98
N-439-1	Use of 20Cr-18Ni-6Mo (Alloy UNS S31254) Forgings, Plate, Seamless and Welded Pipe, and Welded Tube, Class 2 and 3 Construction, Section III, Division 1	9/18/01
N-440-1	Use of 20Cr-18Ni-6Mo (Alloy UNS J93254) Castings, Class 2 and 3 Construction, Section III, Division 1	9/18/01
N-441-2	Use of 20Cr-18Ni-6Mo (Alloy UNS S31254) Fittings, Class 2 and 3 Construction, Section III, Division 1	9/18/01
N-442	1977 Addendum to ANSI/ASME PTC 25.3-1976, Safety and Safety Relief Valves, Class 1, 2, 3, and MC, Section III, Division 1	3/8/92
N-443-2	High Yield Strength Cr-Mo Steel, Class 1 Components, Section III, Division 1	1/1/01
N-451	Alternative Rules for Analysis of Piping under Seismic Loading, Class 1, Section III, Division 1	8/14/96
N-459	SA-508 Basic Oxygen-Ladle Furnace Process for Code Construction, Section III, Division 1	3/14/94
N-462	Alternative Rules for Analysis of Piping Products under Seismic Loading, Class 2 and 3 Piping Systems, Section III, Division 1	5/24/96
N-464	Laser Welding of Lap Joints, Section III, Division 1, Classes 2 and 3 Construction	5/9/03
N-466-1	Modified 9Cr-1Mo Material, Section III, Division 1, Classes 1, 2, and 3	8/14/97
N-468	Alternative Method of Earthquake Description for Class 2 and 3 Piping of Low Seismicity Sites, Section III, Division 1	1/1/92
N-470	Class MC Material Requirements [NE-2121(c)], Section III, Division 1	3/8/92
N-474-2	Design Stress Intensities and Yield Strength Values for UNS N06690 with a Minimum Specified Yield Strength of 35 ksi, Class 1 Components, Section III, Division 1	1/1/00
N-475	Materials in Inventory, Section III, Division 1	12/11/92
N-476	Class 1, 2, 3, and MC Linear Component Supports—Design Criteria for Single Angle Members, Section III, Division 1, Subsection NF	7/1/96
N-482	Direct Quenched Stainless Bar, ASTM A 479-88b, Section III, Division 1	3/5/93
N-484-1	Real Time Radioscopic Examination of Welds, Section III, Division 1	12/16/94
N-492-1	Grade 9 Titanium Alloy Tubing, Section III, Division 1, Class 1, 2, and 3	1/1/00
N-493	Alternative Radiographic Acceptance Criteria for Vessels Used as Shipping Casks, Section III, Division 1, Class 1	2/9/15
N-497-1	Use of Fe-Ni-Cr-Mo-N (C-N-3MN) Cast Materials, Section III, Division 1, Class 2 and 3 Construction	1/1/99
N-501	Alternative Rules for NCA-3800, 1990 Addenda, Section III, Division 1	12/31/93
N-502	SA-268, Grade 26-3-3 (UNS S44660), Section III, Classes 2 and 3	1/1/00
N-507	Identification of Welders, Section III, Division 2	7/27/05
N-540	Guidance on Implementation of NCA-3800 Revisions in 1994 Addenda, Section III, Division 1	6/30/98
N-549	Stamping and Flow Certification of Rupture Disk Devices, Classes 2 and 3, Section III, Division 1	3/19/99
N-550	Alternative Rules for Examination of Welds in Instrument Tubing, Classes 1 and 2, Section III, Division 1	5/20/01
N-551	Alternative Methods of Analysis, NC/ND-3673.1, Class 2 and 3 Applications, Section III, Division 1	8/14/97
N-558	Stamping of Class 2 Vessels Fabricated to Subsection NB, Section III, Division 1	2/11/16
N-559	SA-203, Grade E (Plate) and SA-350, Grade LF3 (Forging), 3.5% Ni Nominal Composition Used in Class 1 Construction, Section III, Division 1	5/24/99
N-572	Use of SG-425 (UNS N08825) Bar and Rods for Class 1 Construction, Section III, Division 1	5/24/99
N-596	Use of Alternative Reference Specimens, Section III, Division 1	2/20/04
N-608	Applicable Code Edition and Addenda, NCA‑1140(a)(2), Section III, Division 1	5/20/01
N-611	Use of Stress Limits as an Alternate to Pressure Limits Subsection NC/ND‑3500, Section III, Division 1	7/1/2013
N-646	Alternative Stress Intensification Factors for Circumferential Fillet Welded or Socket Welded Joints for Class 2 or 3 Piping, Section III, Division 1	11/10/14
N-657	Use of the N-1A Data Report for Spent Fuel Canisters, Section III, Division 1	2/9/15
N-732	Magnetic Particles Examination of forgings for Construction, Section III, Division 1	10/14/11
N-744	Use of Metric Units Boiler and Pressure Vessel Code, Section III, Divisions 1 and 3, and Section V and IX	2/11/16
N-802	Rules for Repair of Stamped Components by the N-Certificate Holder That Originally Stamped the Component, Section III, Division 1	8/12/12
1141-7	Foreign Produced Steel	7/23/76
1434-1	Postweld Heat Treatment of SA-487 Class 8N Steel Castings, Section III	1/1/78
1461-1	Electron Beam Welding, Section I, III, and VIII, Division 1 and 2	2/16/77
1470-2	External Pressure Charts for High-Strength Carbon Steels and for Low‑Alloy Steels, Section VIII, Division 1 and 2, and Section III	11/4/74
1471-1	Vacuum Electron Beam Welding of Tube Sheet Joints, Section III	1/1/78
1475-1	Ferritic-Austenitic Stainless Steel Seamless Tubes for Section III, Class 2 and 3 Construction	7/1/75
1477-1	Use of 1970 Addenda of ANSI B31.7, Section III	1/1/78
1494-1	Weld Procedure Qualification Test, Section III	1/1/78
1506	Stress Intensification Factors, Section III, Class 2 and 3 Piping	1/1/78
1515	Ultrasonic Examination of Ring Forgings for Shell Sections, Section III, Class 1 Vessels	7/1/77
1529	Materials for Instrument Line Fittings, Section III	7/1/73
1531	Electrical Penetrations, Special Alloys for Electrical Penetration Seals, Section III	3/21/77
1532	Section III, Class 3 Components Made of 8 Percent and 9 Percent Nickel Steel	1/1/78
1533	Pressure Temperature Ratings of SA-351 Grades CF8A, CF3, and CF3M, Section III	7/1/75
1535-2	Hydrostatic Testing of Section III, Class 1 Valves	3/21/77
1536	Closing Seam for Electrical Penetrations for Section III, Class 2, 3, and MC	7/1/77
1553-1	Upset Heading and Roll Threading of SA-453 for Bolting in Section III	1/1/76
1555-1	Certification of Safety Relief Valves, Section III, Division 1	1/1/78
1567	Testing Lots of Carbon and Low Alloy Steel Covered Electrodes, Section III	1/1/78
1568	Testing Lots of Flux Cored and Fabricated Carbon and Low Alloy Steel Welded Electrodes, Section III	1/1/78
1573	Vacuum Relief Valves, Section III	1/1/78
1574	Hydrostatic Test Pressure for Safety Relief Valves, Section III	12/31/74
1580-1	Buttwelded Alignment Tolerance and Acceptable Slopes for Concentric Centerlines for Section III, Class 1, 2, and 3 Construction	1/1/78
1581	Power-Operated Pressure Relief Valves, Section III	3/1/79
1583	Use of 80-40 Carbon Steel Castings, Section III	3/21/77
1587	SA-508 Class 3 Forgings with 0.4/1.0 Ni for Section III and VIII, Division 2 Construction	12/31/75
1590	Chemical Analysis Variations, Section III Construction	3/21/77
1601	Limits of Reinforcement for Two-Thirds Area, Section III, Class 1	7/1/74
1602-1	Use of SB-42 Alloy 122, SB-111 Alloys 122, 715 and 706 and SB-466 Alloys 706 and 715, Section III, Class 2 and 3 Components	12/31/74
1603	Toughness Tests When Cross-Section Limits Orientation and Location of Specimens	7/1/74
1605	Cr-Ni-Mo-V Bolting Material for Section III, Class 1 Components	3/17/80
1608-1	Use of ASME SB-265, SB-337, SB-338, and SB-381, Grades 1, 2, 3, and 7 Unalloyed Titanium and ASTM B‑363 Titanium Welding Fittings, Section III, Class 2 and 3 Components	3/21/77
1613	Use of SA-372 Class IV Forgings, Section III Construction	1/1/78
1614	Hydrostatic Testing of Piping Prior To or Following the Installation of Spray Nozzles for Section III, Classes 1, 2, and 3 Piping Systems	1/1/79
1615	Use of A587-73, Section III, Class 3 Construction	1/1/78
1616	Ultrasonic Examination of Seamless Austenitic Steel Pipe, Section III, Class 1 Construction	7/1/75
1622	PWHT of Repair Welds in Carbon Steel Castings, Section III, Class 1, 2, and 3	1/1/76
1623	Design by Analysis for Section III, Class 1 Sleeve-Coupled and Other Patented Piping Joints	3/1/79
1625	Repair of Section III, Class 2 and 3 Tanks	12/31/74
1633	Brazing of Seats to Class 1, 2, and 3 Valve Body or Bonnets, Section III	1/1/78
1637	Effective Date for Compliance with NA-3700 of Section III	1/1/75
1645	Use of DeLong Diagram for Calculating the Delta Ferrite Content of Welds in Section III, Class 1, 2, and CS Construction	1/1/76
1648	SA-537 Plates for Section III, Class 1, 2, 3, and MC Components	7/1/76
1649	Modified SA-453-GR 660 for Class 1, 2, 3, and CS Construction	1/1/76
1650	Use of SA-414 Grade C for Class 2 and 3 Components, Section III, Division 1	12/31/74
1651	Interim Requirements for Certification of Component Supports, Section III, Subsection NF	3/1/79
1657	Stress Criteria for Class 2 and 3 Atmospheric and Low Pressure (0–15 psig) Steel Storage Tanks	7/1/77
1659	Interconnection of Two Piping Systems for Section III, Class 1, 2, and 3 Construction	7/1/77
1661	Postweld Heat Treatment P-No.1 Materials for Section III, Class 1 Vessels	1/1/78
1662	Shop Assembly of Components, Appurtenances, and Piping Subassemblies for Section III, Class 1, 2, 3, and MC Construction	1/1/78
1664	Use of Cr-Ni-Fe-Mo-Cu-Cb Stabilized Alloy Cb-3 for Section III, Class 2 and 3 Construction	3/21/77
1666	Use of SB-12, Alloy 122 for Class 2 and 3 Construction	7/1/75
1672	Nuclear Valves for Section III, Division 1, Class 1, 2, 3 Construction	3/21/77
1675	Tubesheet to Shell or Formed Head Weld Joints, Section III, Class 1 Vessels	7/1/76
1676	Clarification of Stress Intensities in Curved Pipe or Welded Elbows, Section III	7/1/76
1678	Butterfly Valves of Circular Cross Section Larger Than 24 in. NPS for Section III, Class 2 and 3 Construction	1/1/80
1682-1	Alternate Rules for Material Manufacturers and Suppliers, Section III, Subarticle NA‑3700	12/31/75
1683-1	Bolt Holes for Section III, Class 1, 2, 3 and MC Component Supports	7/1/76
1684	A637 Grade 718 for Bolting Class 1 and 2 Construction	1/1/76
1685	Furnace Brazing Section III, Class 1, 2, 3 and MC Construction	1/1/78
1686	Furnace Brazing, Section III, Subsection NF, Component Supports	1/1/78
1690	Stock Materials for Section III Construction, Section III, Division 1	1/1/77
1691	Ultrasonic Examination in Lieu of Radiography of Repair Welds for Vessels, Section III, Class 1	1/1/78
1703	Brazing of Copper Alloys, Section III, Class 2	1/1/78
1706	Data Report Forms for Component Supports, Section III, Class 1, 2 and 3	12/31/75
1713	Small Material Items, Section III, Division 1, Class 1, 2, 3, CS and MC	12/31/75
1718	Design of Structural Connections for Linear Type Component Supports, Section III, Division 1, Class 1, 2 and 3 and MC	7/1/76
1719	Single-Welded, Full-Penetration Sidewall Butt Joints in Atmospheric Storage Tanks, Section III, Division 1, Class 2	7/1/76
1728	Steel Structural Shapes and Small Material Products for Components Supports, Section II, Division 1 Construction	7/1/77
1740	Weld Metal Test, Section III, Class 1, 2, 3, MC, and CS	7/1/76
1741-1	Interim Rules for the Required Number of Impact Tests for Rolled Shapes, Section III, Division 1, Subsection NF, Components Supports	1/1/78
1742	Use of SB-75 Annealed Copper Alloy 122, Section III, Division 1, Class 2 Construction	7/1/76
1743	Use of SB-98 Cu-SiB Rod CDA651 Section III, Division 1, Class 2 Components	7/1/76
1760	Maximum Dimensions for Isolated Pores in Welds—Class 1 Components, Section III, Division 1	7/1/77
1765	Machining after Hydrostatic Testing Class 2 and 3 Construction, Section III, Division 1	7/1/77
1766	Testing Requirements for Welding Materials, Class 1, 2, 3, MC, and CS Construction, Section III, Division 1	7/1/77
1767	Examination of Tubular Products without Filler Metal—Class 1 Construction, Section III, Division 1	1/1/77
1768	Permanent Attachments to Containment Vessels—Class MC, Section III, Division 1	1/1/78
1769-1	Qualification of NDE Level III Personnel, Section III, Division 1	10/1/77
1773	Use of Other Product Forms of Materials for Valves, Section III, Division 1	7/1/77
1775	Data Report Forms for Core Support Structures, Class CS, Section III, Division 1	8/13/79
1777	Use of SA-106, Grade C in Class MC Construction, Section III, Division 1	7/1/77
1787	Depth of Weld Repairs for Forgings, Section III, Division 1, Class 1, 2, 3, MC and CS Construction	1/1/78
1798	Use of ASTM A352-75, Grades LCA and LCC, Section III, Division 1, Class 1, 2, and 3	1/1/78
1808	F-Number Classification of Low Alloy and Carbon Steel Bare Rod Electrodes, Sections I, II, III, IV, V, VIII, and IX.	1/1/78
1810	Testing Lots of Carbon Steel Solid, Bare Welding Electrode or Wire, Section III, Division 1, Class 1, 2, 3, MC, and CS	3/3/80
1819	Use of Type XM-19 for Construction, Section III, Division 1, Class 1, 2, 3	1/1/78

4. Annulled Conditionally Acceptable Section III Code Cases

The NRC conditionally approved the Code Cases listed in Table 4; however, they were subsequently annulled by ASME. To assist users, new annulled Code Cases are shaded in grey to distinguish them from those listed in previous versions of this guide.

Table 4. Annulled Conditionally Acceptable Section III Code Cases

CODE CASE NUMBER	TABLE 4 ANNULLED CONDITIONALLY ACCEPTABLE SECTION III CODE CASES TITLE/CONDITION	ANNULMENT DATE
N-11-5 (1414-5)	High Yield Strength Cr-Mo Steel for Section III, Division 1, Class 1 Vessels Each referencing safety analysis report should provide the information required by Note 1 in the Code Case.	8/29/80
N-31-1	Elastomer Diaphragm Valves, Section III, Division 1, Classes 2 and 3 Each applicant who applies the Code Case should indicate in the referencing safety analysis report that the service life of the elastomer diaphragm should not exceed the manufacturer’s recommended service life. This recommended service life should not exceed one-third of the minimum cycle life as established by the requirements of Paragraph 3 of the Code Case. In addition, the service life of the elastomer diaphragm should not exceed 5 years, and the combined service and storage life of the elastomer diaphragm should not exceed 10 years.	7/1/93
N-32-4	Hydrostatic Testing of Embedded Class 2 and Class 3 Piping for Section III, Division 1 Construction The acceptance of Code Case N-32-4 was based on the following clarification and interpretation. Code Case N‑32‑4 does not replace Paragraph NC/ND‑6129, “Provisions for Embedded or Inaccessible Welded Joints in Piping,” of the Code. The intent of the Code Case is to (1) provide additional testing above Code requirements and (2) permit liquid penetrant or magnetic particle testing in place of radiographic testing for Class 3 piping with a 3/8‑inch nominal wall thickness or less. Paragraph (1) contains an additional requirement to the Code. It was, therefore, acceptable but unnecessary to include in the Code Case. Paragraph (2) is a variation in the volumetric examination technique and was acceptable as written. Paragraph (3) contains an additional requirement and is not a relaxation of the Code. It was, therefore, acceptable but unnecessary to include in the Code Case.	3/16/84
N-92 (1698)	Waiver of Ultrasonic Transfer Method, Section III, V, and VIII, Division 1 The material from which the basic calibration block is fabricated should be of the same product form, alloy, and heat treatment as the material being examined. Alloys of equivalent P‑number groupings may be used for the fabrication of calibration blocks if adjustments to signal height can be made to compensate for sound beam attenuation difference between the calibration block and the material under examination by following the transfer method procedure in the 1977 Edition of ASME Code, Section V, Article 5, T‑535.1(d).	7/13/81
N-100 (1711)	Pressure Relief Valve Design Rules, Section III, Division 1, Class 1, 2 and 3 The safety analysis report should provide the following information: If stress limits are used in excess of those specified for the upset operating condition, it should be demonstrated how the pressure relief function is ensured. Refer to paragraph 3.1, Section I, of the Code Case for Class and paragraph 3.2, Section II, of the Code Case for Class 2 and 3 pressure relief valves. If Code Case 1660 is to be used in conjunction with the Code Case, it should be stated that the stress limits of Code Case 1660 supersede those of paragraph 3.2(b), Section I, of Code Case 1711. Functional assurance of (1) above is required in all situations.	1/1/83
N-106-2 (1720-2)	Weld End Preparation for Section III, Division 1 Construction The acceptance of weld‑end preparations other than those shown in Figures 1, 2, and 3 of the Code Case should be evaluated on a case-by-case basis.	8/14/93
N-110 (1727)	Alternate Test Fluids, Section III, Division 1 The applicant should provide justification in the referencing safety analysis report for the fluid selected for use in the pressure test. The information provided should demonstrate that the fluid selected will not have deleterious effects on the material of the pressure boundary and that the fluid may be safely used at the specified temperature and pressure of the test. When the fluid selected for use is the operating fluid, additional information is not required.	1/1/79
N-116 (1734)	Weld Design for Use for Section III, Division 1, Class 1, 2, 3 and MC Construction of Component Supports If the configuration of Figure 1 of the Code Case is used for Class 1 and MC component supports, full‑penetration welds should be used. The application of the configuration shown in Figures 2 and 3 should be restricted to the welding of cans for spring encapsulation in spring hangers. In Figure 3, the length of the leg of the fillet weld adjacent to the plate should be equal to the thickness of the exposed edge of the plate. In addition, the leg of the fillet weld adjacent to the shell should be equal to the thickness of the exposed end of the shell.	1/1/78
N-146-1 (1780-1)	Hydrostatic Testing and Stamping of Components, Section III, Division 1, Construction On a generic basis, the application of the Code Case is limited to pumps and valves. Application to other components should be treated on a case-by-case basis. Each licensing application in which the Code Case is to be used should contain information showing that, as a minimum, the closure fixture will impose loads that result in stresses equal to or greater than those induced during the hydrostatic test of a complete pump assembly. A closure fixture for the part being tested that is similar in size and shape to the actual mating part is considered adequate to impose these loads. It is not intended that the hydrostatic testing simulate piping reaction loadings.	1/1/82
N-175 (1818)	Welded Joints in Component Standard Supports, Section III, Division 1 That portion of the unwelded housing that is limited to 90 degrees maximum should include a minimum of two sectors that are uniform in length.	7/1/79
N-199	Intervening Elements, Section III, Division 1, Classes 1, 2, 3, and MC Component Construction The applicants should provide information in the referencing safety analysis report that demonstrates that all intervening elements have been designed in compliance with the requirements of the respective design specification.	1/1/81
N-208-2	Fatigue Analysis for Precipitation Hardening Nickel Alloy Bolting Material to Specification SB-637 N07718 for Class 1 Construction, Section III, Division 1 (1) In Figure A, the words “No mean stress” shall be implemented with the understanding that it denotes “Maximum mean stress.” (2) In Figure A, σy shall be implemented with the understanding that it denotes σmax.	10/14/11
N-238	High Temperature Furnace Brazing of Seat Rings in Valve Bodies or Bonnets for Section III, Division 1, Class 1, 2, and 3 Valves The furnace brazing process procedure qualification should verify nonsensitization, as given in Practices A or E of ASTM A 262-70, “Standard Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels” (Ref. 9), or ASTM A 708-74, “Practice for Detection of Susceptibility to Intergranular Corrosion in Severely Sensitized Austenitic Stainless Steels” (Ref. 10), whenever materials subject to sensitization are to be brazed. Documentation is required for the use of a nonsensitizing brazing procedure for valves produced to this Code Case.	1/1/82
N-242-1	Materials Certification, Section III, Division 1, Classes 1, 2, 3, MC, and CS Construction Applicants should identify, in their safety analysis reports, the components and supports for which the Code Case is being applied and should specify the respective paragraphs of the Code Case.	6/30/84
N-252	Low Energy Capacitive Discharge Welding Method for Temporary or Permanent Attachments to Components and Supports, Section III, Division 1, and XI The applicant should indicate, in the safety analysis report, the application, the material, and the material thickness to which the strain gage or thermocouple will be attached by CD welding.	7/1/82
N-260-2	Weld Repair of SA-182 Type 316 Forgings, Section III, Division 1, Classes 1, 2, 3, and MC Type 308L welding materials should not be used to repair Grade F 316 N forgings because of the difference in strength levels.	12/5/88
N-263	Alternate Thread Forms, Series and Fits for Component Supports, Section III, Division 1 The safety analysis report should do the following: Describe the application. Justify the need for the use of the Code Case. Demonstrate that the support design will withstand maximum conditions of loading with the worst combination of thread tolerance.	3/17/83
N-274	Alternative Rules for Examination of Weld Repairs for Section III, Division 1 Construction The ultrasonic examination procedures shall be proven by actual demonstration to the satisfaction of the authorized nuclear inspector that the procedures are capable of detecting unacceptable cracks in accordance with Section XI, requirements.	6/30/86
N-275	Repair of Welds, Section III, Division 1 Use of the Code Case applies only when the removal of an indication requires that the full weld thickness be removed and when the backside of the weld assembly joint is not accessible for the removal of examination material. If an indication is removed and weld‑metal layers still remain, gouging through the wall to qualify for use of the Code Case is not acceptable. Instead, the cavity must be examined when such an indication has been removed.	12/31/83
N-279	Use of Torquing as a Locking Device for Section III, Division 1, Class 1, 2, 3, and MC Component Supports When torquing or other preloading is used as a locking device and the joint is later unloaded or disassembled, the bolting should be replaced unless it can be demonstrated or proved to the authorized nuclear inspector that the original bolting has not been permanently strained.	7/13/81
N-292	Depositing Weld Metal Prior to Preparing Ends for Welding, Section III, Division 1, Class 1, 2, and 3 Class 3 piping that is longitudinally welded and that has a weld efficiency factor of 1.0, as selected from ASME Code, Table ND‑3613.4-1, “Weld Joint Efficiency Factor,” must receive a 100‑percent volumetric examination (radiographic testing or ultrasonic testing) of the deposited weld metal in accordance with ASME Code, ND‑5000, “Examination.”	2/20/04
N-310-1	Certification of Bolting Materials, Section III, Division 1, Class 1, 2, 3, MC, and CS Each applicant who applies the Code Case should include the answers to the following questions in the referencing safety analysis report: (1) Why does the bolting not meet ASME Code, NCA‑3800 (or NA‑3700)? (2) Where will the bolting be used in the plant? (3) How will the applicant show that the bolting material properties required by the equipment support design specification will be present in the actual bolting material?	7/1/82
N-314	Alternate Rules for Thread Engagement, Section III, Division 1 Applicants should identify the following items in their safety analysis report: (1) the minimum length of thread engagement (2) the procedure used to establish thread engagement	5/11/84
N-348 N-348-1 N-348-2	Use of SA-574 Socket Weld Head Cap Screws, Section III, Division 1 Applicants’ safety analysis reports should justify why the use of these socket head cap screws will not result in early failure from stress‑corrosion cracking.	9/7/85 2/20/89 8/14/93
N-350	Postweld Heat Treatment Thickness of Material, Section III, Division 1 Applicants wishing to use this Code Case for materials other than P‑1 materials should demonstrate that the use of this Code Case will not adversely affect the required material properties.	9/5/85
N-383-1	Weld Repair of SA-182 Austenitic Forgings, Section III, Division 1, Classes 1, 2, and 3 Applicants who apply the provisions of this Code Case to permit material manufacturers to weld repair austenitic forgings without resolution heat treatment should give the NRC staff (through the safety analysis report) a justification as to why this is acceptable for their applications, including their evaluation of the susceptibility for stress‑corrosion cracking.	9/5/85
N-397	Alternative Rules to the Spectral Broadening Procedures of N-1226.3 for Classes 1, 2, and 3 Piping, Section III, Division 1 The Code Case is acceptable for specific plant applications on a case‑by‑case basis, pending revision of RG 1.122, “Development of Floor Design Response Spectra for Seismic Design of Floor‑Supported Equipment or Components” (Ref. 11).	2/20/87
N-398	Reporting of Charpy-V Notch Test Results, Section III, Division 1 The Code Case is not acceptable for steam generator or reactor coolant pump supports. Applicants wishing to use this Code Case should indicate in the safety analysis report the component supports to which the Code Case is applied for review on a case‑by‑case basis.	2/20/87
N-404	Annealed Alloy UNS N06625 Over UNS N06600 Bimetallic Tubing, Section III, Division 1, Class 1 The outside layer of the bimetallic tubing should be limited to a minimum of 5 percent and to a maximum of 40 percent of the wall thickness. The tolerance on the outside layer of material should not exceed -0.000 to +0.007 inch of the specified design wall thickness.	12/11/95
N-411-1	Alternative Damping Values for Response Spectra Analysis of Class 1, 2, and 3 Piping, Section III, Division 1 (1) The Code Case damping should be used completely and consistently, if it is used at all. (For equipment other than piping, the damping values specified in RG 1.61, “Damping Values for Seismic Design of Nuclear Power Plants” (Ref. 12), should be used.) (2) The damping values specified may be used only in those analyses in which current seismic spectra and procedures have been employed. Such use is to be limited only to response spectral analyses [similar to that used in the study supporting its acceptance, NUREG/CR-3526, “Impact of Changes in Damping and Spectrum Peak Broadening on the Seismic Response of Piping Systems” (Ref. 13)]. The acceptance of the use with other types of dynamic analyses (e.g., time-history analyses or independent support motion method) is pending further justification. (3) When used for reconciliation work or for support optimization of existing designs, the effects of increased motion on existing clearances and online mounted equipment should be checked. (4) This Code Case is not appropriate for analyzing the dynamic response of piping systems using supports designed to dissipate energy by yielding (i.e., the design of which is covered by Code Case N‑420). (5) This Code Case does not apply to piping in which stress corrosion‑cracking has occurred unless a case-specific evaluation is made and is reviewed by the NRC staff.	5/5/00
N-430	Alternative Requirements for Welding Workmanship and Visual Acceptance Criteria for Class 1, 2, 3 and MC Linear-Type and Standard Supports, Section III, Division 1 (1) The applicant should demonstrate that the applicable supports are not subject to cyclic loading in excess of 20,000 cycles. (2) The first sentence of 3.0(f)(1) should be replaced with the following: “For material 3/8 in. and less nominal thickness, undercut depth of 1/32 in. on one side of the member for the full length of the weld, or 1/32 in. on one side for one-half the length of the weld, and 1/16 in. for one-fourth of the length of the weld on the face of a rectangular tube or one-fourth the length of the weld on the same side of the member is acceptable.”	7/1/93
N-595-4	Requirements for Spent Fuel Storage Canisters, Section III, Division 1 The canisters must be made from austenitic stainless steel Type 304 or 316.	10/14/11
N-656	Rules for the Construction of Inner Transportation Containments, Section III, Division 3 The inner transportation containment must contain only solid and dry material.	5/11/10
N-755-4	Use of Polyethylene (PE) Class 3 Plastic Pipe, Section III, Division 1 When performing fusing procedure qualification testing in accordance with paragraphs -2420 and -4330 of this Code Case, the following essential variables must be used for butt fusion joints: Joint Type: A change in the type of joint from that qualified, except that a square butt joint qualifies as a mitered joint. Pipe Surface Alignment: A change in the pipe outside diameter (O.D.) surface misalignment of more than 10 percent of the wall thickness of the thinner member to be fused. PE Material: Each lot of polyethylene source material to be used in production (as mentioned in paragraph (XXVI-2310(c)). Wall Thickness: Each thickness to be fused in production (as mentioned in paragraph (XXVI-2310(c)). Diameter: Each diameter to be fused in production (as mentioned in paragraph (XXVI-2310(c)). Cross-sectional Area: Each combination of thickness and diameter (as mentioned in paragraph (XXVI-2310(c)). Position: Maximum machine carriage slope when greater than 20 degrees from horizontal (as mentioned in paragraph (XXVI-4321(c)). Heater Surface Temperature: A change in the heater surface temperature to a value beyond the range tested (as mentioned in paragraph (XXVI-2321). Ambient Temperature: A change in ambient temperature to less than 50⁰F (10⁰C) or greater than 125⁰F (52⁰C) (as mentioned in paragraph (XXVI-4412(b)). Interfacial Pressure: A change in interfacial pressure to a value beyond the range tested (as mentioned in paragraph (XXVI-2321). Decrease in Melt Bead Width: A decrease in melt bead size from that qualified. Increase in Heater Removal Time: An increase in heater plate removal time from that qualified. Decrease in Cool-down Time: A decrease in the cooling time at pressure from that qualified. Fusing Machine Carriage Model: A change in the fusing machine carriage model from that tested (as mentioned in paragraph (XXVI-2310(d)). When performing procedure qualification for High Speed Tensile Impact testing of butt fusion joints in accordance with XXVI-2300 or XXVI-4330, if the specimen breaks away from the fusion zone it must be retested. When performing fusing operator qualification bend tests of butt fusion joints in accordance with XXVI-4342, guided side bend testing must be used for all thicknesses greater than 1.25 inches.	1/1/22
1361-2	Socket Welds, Section III Code Case 1361-2 was acceptable when used in connection with Section III, Paragraph NB-3356, “Fillet Welds.”	3/1/79
1412-4	Modified High Yield Strength Steel for Section III, Division 1, Class 1 Vessels Each referencing safety analysis report should provide the information required by Note 1 in the Code Case. The material given in the “Inquiry” section of the Code Case should be SA-508, Class 4b, instead of SA‑508, Class 4.	1/1/77
1423-2	Wrought Type 304 and 316 with Nitrogen Added, Sections I, III, VIII, Divisions 1 and 2 Code Case 1423-2 was acceptable subject to compliance with the recommendations in RG 1.31, “Control of Ferrite Content in Stainless Steel Weld Metal” (Ref. 14), and RG 1.44, “Control of the Use of Sensitized Stainless Steel” (Ref. 15).	7/1/77
1521-1	Use of H-Grades of SA-240, SA-479, SA-336, and SA-358, Section III Code Case 1521-1 was acceptable subject to compliance with the recommendations contained in RG 1.31 (Ref. 14) and RG 1.44 (Ref. 15).	1/1/78
1528-3	High Strength Steel SA-508, Class 2 and SA-541, Class 2 Forgings, Section III, Class 1 Components Each referencing safety analysis report should provide the information required by Note 1 in the Code Case.	1/1/78
1569	Design of Piping for Pressure Relief Valve Station, Section III Code Case 1569 was acceptable subject to compliance with the recommendations in RG 1.67, “Installation of Over‑Pressure Protection Devices” (Ref. 16).	7/1/79
1606-1	Stress Criteria Section III, Classes 2 and 3 Piping Subject to Upset, Emergency, and Faulted Operating Conditions Code Case 1606-1 was acceptable subject to the interpretation that the stress limit designations of “Upset,” “Emergency,” and “Faulted” do not necessarily imply agreement with specified plant conditions that apply to ASME Code Class 2 and 3 components for fluid systems. The design specifications should establish and justify these designations.	7/1/77
1607-1	Stress Criteria for Section III, Classes 2 and 3 Vessels Designed to NC/NC‑3300 Excluding the NC-3200 Alternate Code Case 1607-1 was acceptable subject to the interpretation that the stress limit designations of “Upset,” “Emergency,” and “Faulted” do not necessarily imply agreement with specified plant conditions that apply to ASME Code Class 2 and 3 components for fluid systems. The design specifications should establish and justify these designations.	7/1/77
1635-1	Stress Criteria for Section III, Class 2 and 3 Valves Subjected to Upset, Emergency, and Faulted Operating Conditions Code Case 1635-1 was acceptable subject to the interpretation that the stress limit designations of “Upset,” “Emergency,” and “Faulted” do not necessarily imply agreement with specified plant conditions that apply to ASME Code Class 2 and 3 components for fluid systems. The design specifications should establish and justify these designations.	7/1/77
1636-1	Stress Criteria for Section III, Class 2 and 3 Pumps Subjected to Upset, Emergency, and Faulted Operating Conditions Code Case 1636-1 was acceptable subject to the interpretation that the stress limit designations of “Upset,” “Emergency,” and “Faulted” do not necessarily imply agreement with specified plant conditions that apply to ASME Code Class 2 and 3 components for fluid systems. The design specifications should establish and justify these designations.	7/1/77
1689-1	Alternate PWHT Time and Temperature for SA-182 Grade F‑22, SA-387 Grade 22, Class 2, and SA-335 Grade P-22 Section III, Class 1, 2, 3 and CS The alternate postweld heat treatment (PWHT) should be prequalified along with the applicable welding procedure in accordance with Section IX.	1/1/78
1783-1	Qualification of Nondestructive Examination Personnel, Section III, Division 1 The first sentence of Paragraph 1 of the Code Case should be replaced with the following: “The certification of the Level III nondestructive examination personnel for the purpose of this Section of the Code will be the responsibility of the employer of the Level III individual. If the employer is not a Certificate Holder, then the verification of such certificate is the responsibility of the Certificate Holder.”	1/1/79

5. Code Cases Superseded by Revised Code Cases

The Code Cases listed in Table 5 were approved in prior versions of this guide and have since been superseded by revised Code Cases (on or after July 1, 1974). The date in Column 3 indicates the date on which the ASME approved the revision to the Code Case. Note that the NRC unconditionally approved the Code Cases listed without conditions. The versions of the Code Cases listed in Table 5 cannot be applied by the licensee or applicant for the first time after the effective date of this RG. To assist users, changes to superseded Code Cases are shaded in grey to distinguish them from those listed in previous versions of this guide. (Note: The NRC did not approve some of these Code Cases in previous versions of this guide.)

Table 5. Section III Code Cases That Have Been

Superseded by Revised Code Cases on or after July 1, 1974

CODE CASE NUMBER	TABLE 5 CODE CASES THAT HAVE BEEN SUPERSEDED BY REVISED CODE CASES ON OR AFTER JULY 1, 1974	REVISION DATE
N-4-11 (1337-11) N-4-12	Special Type 403 Modified Forgings or Bars, Section III, Division 1, Class 1 and CS	1/12/05 2/12/08
N-5 (1344-5)	Nickel-Chromium, Age-Hardenable Alloys (Alloy X750), Section III	12/13/82
N-7 (1358-5)	High Yield Strength Steel, Section III, Division 1, Class 1 Vessels Each referencing safety analysis report should provide the information required by Note 1 in the Code Case.	12/13/82
N-20 (1484-3) N-20-1	SB-163 Nickel-Chromium-Iron Tubing (Alloy 600 and 690) at Nickel‑Iron‑Chromium Alloy 800 at a Specified Minimum Yield Strength of 40.0 ksi, Section III, Division 1, Class 1	9/5/85 12/7/87
N-20-2 N-20-3	SB-163 Nickel-Chromium-Iron Tubing (Alloy 600 and 690) at Nickel‑Iron‑Chromium Alloy 800 at a Specified Minimum Yield Strength of 40.0‑ksi and Cold Worked Alloy 800 at a yield strength of 47.0‑ksi, Section III, Division 1, Class 1	11/30/88 2/26/99
N-31 (1540-2)	Elastomer Diaphragm Valves, Section III, Class 2 and 3 Each applicant who applies the Code Case should indicate in the referencing safety analysis report that the service life of the elastomer diaphragm should not exceed the manufacturer’s recommended service life. This recommended service life should not exceed one-third of the minimum cycle life as established by the requirements of Paragraph 3 of the Code Case. In addition, the service life of the elastomer diaphragm should not exceed 5 years, and the combined service and storage life of the elastomer diaphragm should not exceed 10 years.	7/18/85
N-55 (1609-1)	Inertia and Continuous Drive Friction Welding, Section I, III, IV, VIII, Division 1 and 2, and IX	4/5/84
N-60 (1618-2) N-60-1	Material for Core Support Structures, Section III, Division 1, Subsection NG Welding of age-hardenable Alloy SA-453 Grade 660 and SA‑637 Grade 688 should be performed when the material is in a solution‑treated condition.	5/25/83 9/17/84
N-60-2 N-60-3 N-60-4	Material for Core Support Structures, Section III, Division 1, Subsection NG	9/5/85 5/13/91 2/15/94
	Welding of age-hardenable Alloy SA-453 Grade 660 and SA‑637 Grade 688 should be performed when the material is in a solution‑treated condition. For SA‑479 material, the maximum yield strength should not exceed 90,000 pounds per square inch (psi) because of the susceptibility of this material to environmental cracking.
N-60-5	Material for Core Support Structures, Section III, Division 1, Class 1 The maximum yield strength of strain-hardened austenitic stainless steel shall not exceed 90,000 psi because of the susceptibility of this material to environmental cracking.	2/20/04
N-62-2 (1621-2) N-62-3 N-62-4 N-62-5 N-62-6	Internal and External Valve Items, Section III, Division 1, Class 1, 2 and 3 Line Valves The Code Case requires Class 1 and Class 2 valve manufacturers to meet the provisions of Section III, Article NCA‑4000, and Class 3 valve manufacturers should also meet the provisions of Article NCA‑4000.	7/18/85 9/5/85 7/24/89 12/11/89 5/11/94
N-71-7 (1644-7) N-71-8 (1644-8)	Additional Materials for Component Supports, Section III, Division 1, Subsection NF, Class 1, 2, 3 and MC Component Supports The maximum measured UTS of the component support material should not exceed 170 ksi because of the susceptibility of high‑strength materials to brittleness and stress‑corrosion cracking. Certain applications may exist where a UTS value of up to 190 ksi could be considered acceptable for a material; under this condition, the design specification should specify impact testing for the material. For these cases, the applicant should demonstrate that (1) the impact test results for the material meet the Code requirements and (2) the material is not subject to stress‑corrosion cracking because a corrosive environment is not present and because the component that contains the material has essentially no residual stresses or assembly stresses and it does not experience frequent sustained loads in service.	5/15/78 1/7/80
N-71-9 (1644-9)	Additional Materials for Component Supports Fabricated by Welding, Section III, Division 1, Subsection NF, Class 1, 2, 3, and MC Component Supports In the last sentence of Paragraph 5.3 of the Code Case, reference should be made to Paragraph 4.5.2.2, “Alternate Atmosphere Exposure Time Periods Established by Test,” of the AWS D.1.1 Code for the evidence presented to and accepted by the authorized inspector concerning exposure of electrodes for longer periods of time.	5/11/81
N-71-10 N-71-11	Additional Materials for Component Supports Fabricated by Welding, Section III, Division 1, Subsection NF, Class 1, 2, 3, and MC Component Supports The maximum measured UTS of the component support material should not exceed 170 ksi because of the susceptibility of high‑strength materials to brittleness and stress‑corrosion cracking. Certain applications may exist where a UTS value of up to 190 ksi could be considered acceptable for a material; under this condition, the design specification should specify impact testing for the material. For these cases, the applicant should demonstrate that (1) the impact test results for the material meet Code requirements and (2) the material is not subject to stress‑corrosion cracking because a corrosive environment is not present and because the component that contains the material has essentially no residual stresses or assembly stresses and it does not experience frequent sustained loads in service. The last sentence of Paragraph 5.3 of the Code Case should reference Paragraph 4.5.2.2 of the AWS D.1.1 Code for the evidence presented to and accepted by the authorized inspector concerning exposure of electrodes for longer periods of time.	6/17/82 2/14/83
N-71-12	Additional Materials for Component Supports Fabricated by Welding, Section III, Division 1, Class 1, 2, 3 and MC The maximum measured UTS of the component support material should not exceed 170 ksi in view of the susceptibility of high-strength materials to brittleness and stress‑corrosion cracking. Certain applications may exist where a UTS value of up to 190 ksi could be considered acceptable for a material; under this condition, the design specification should specify impact testing for the material. For these cases, the applicant should demonstrate that (1) the impact test results for the material meet Code requirements and (2) the material is not subject to stress‑corrosion cracking because a corrosive environment is not present and because the component that contains the material has essentially no residual stresses or assembly stresses and it does not experience frequent sustained loads in service. The last sentence of Paragraph 5.3 of the Code Case should reference Paragraph 4.5.2.2 of the AWS D.1.1 Code for the evidence presented to and accepted by the authorized inspector concerning exposure of electrodes for longer periods of time. Paragraph 16.2.2 is not acceptable as written and should be replaced with the following: “When not exempted by 16.2.1, above, the postweld heat treatment shall be performed in accordance with NF-4622 except that for ASTM A-710 Grade A material, it should be at least 1000°F (540°C) and should not exceed 1150°F (620°C) for Class 1 and Class 2 material and 1175°F (640°C) for Class 3 material. The new holding time at temperature for weld thickness (nominal) should be 30 minutes for 2 inches or less, 1 hour per inch for thickness over 2 inches to 5 inches, and 5 hours plus 15 minutes for each additional inch over 5 inches.”	2/20/84
N-71-13 N-71-14 N-71-15 N-71-16 N-71-17 N-71-18	Additional Materials for Subsection NF, Classes 1, 2, 3 and MC Component Supports Fabricated by Welding, Section III, Division 1 The maximum measured UTS of the component support material must not exceed 170 ksi because of the susceptibility of high‑strength materials to brittleness and stress‑corrosion cracking. Certain applications may exist for which a UTS value of up to 190 ksi could be considered acceptable for a material; under this condition, the design specification must specify impact testing for the material. For these cases, the applicant must demonstrate that (1) the impact test results for the material meet the Code requirements and (2) the material is not subject to stress‑corrosion cracking because a corrosive environment is not present and because the component that contains the material has essentially no residual stresses or assembly stresses and it does not experience frequent sustained loads in service. In the last sentence of Paragraph 5.3 of the Code Case, reference must be made to Paragraph 5.3.2.3, “Alternative Atmosphere Exposure Time Periods Established by Tests,” of the AWS D1.1 Code for the evidence presented to and accepted by the authorized inspector concerning exposure of electrodes for longer periods of time. Paragraph 15.2.2 of the Code Case is not acceptable as written and must be replaced with the following: “When not exempted by 15.2.1 above, the postweld heat treatment must be performed in accordance with NF‑4622 except that ASTM A-710 Grade A Material must be at least 1000°F (540°C) and must not exceed 1150°F (620°C) for Class 1 and Class 2 material and 1175°F (640°C) for Class 3 material.” The new holding time at temperature for weld thickness (nominal) must be 30 minutes for 2 inches or less; 1 hour per inch for thickness over 2 inches to 5 inches; and for thicknesses over 5 inches, 5 hours plus 15 minutes for each additional inch over 5 inches. The fracture toughness requirements as listed in this Code Case apply only to piping supports, not to Class 1, Class 2, and Class 3 component supports.	12/5/85 12/16/86 2/12/93 12/31/96 12/8/00 11/8/12
N-71-19 N-71-20	Additional Materials for Subsection NF, Classes 1, 2, 3 and MC Component Supports Fabricated by Welding, Section III, Division 1 The maximum measured ultimate tensile strength (UTS) of the component support material must not exceed 170 ksi because of the susceptibility of high‑strength materials to brittleness and stress‑corrosion cracking. In the last sentence of Paragraph 5.2 of Code Case N7119, reference must be made to Paragraph 5.3.2.3, “Alternative Atmosphere Exposure Time Periods Established by Test,” of the AWS D1.1 Code for the evidence presented to and accepted by the Authorized Inspector concerning exposure of electrodes for a longer period of time. Paragraph 16.2.2 of Code Case N-71-19 is not acceptable as written and must be replaced with the following: “When not exempted by 16.2.1 above, the post weld heat treatment must be performed in accordance with NF4622 except that ASTM A-710 Grade A Material must be at least 1000°F (540°C) and must not exceed 1150°F (620°C) for Class 1 and 2 material and 1175°F (640°C) for Class 3 material.” The new holding time at temperature for weld thickness (nominal) must be 30 minutes for welds 0.5 inch or less; 1 hour per inch of thickness for welds over 0.5 inch to 5 inches; and for thicknesses over 5 inches, 5 hours plus 15 minutes for each additional inch over 5 inches. The fracture toughness requirements as listed in this Code Case apply only to piping supports and not to Class 1, 2 and 3 component supports. When welding P-number materials listed in the Code Case, the corresponding S-number welding requirements shall apply.	6/30/16 1/11/21
N-95-1 (1701-1)	Determination of Capacities of Vacuum Relief Valves, Section III, Division 1 and 2, Class MC	7/9/79
N-102-1 (1714-2)	Postweld Heat Treatment of P-1 Material, Section III, Class MC	8/28/78
N-119-2 (1739-2) N-119-3 (1739-3 N-119-4 (1739-4) N-119-5	Pump Internal Items, Section III, Division 1, Class 1, 2, and 3	8/25/80 12/1/80 7/18/85 9/5/85
N-122	Stress Indices for Structural Attachments, Class 1, Section III, Division 1	7/24/89
N-133 (1761-1)	Use of SB-148 Alloy CA954 for Section III, Division 1, Class 2 or 3 Flanged End Valves	1/14/77
N-133-1 N-133-2	Use of SB-148 Alloys 952 and 954, Section III, Division 1, Class 3	5/19/85 7/18/85
N-154 (1791)	Projection Resistance Welding of Valve Seats, Section III, Division 1, Class 1, 2 and 3 Valves	7/18/85
N-155-2	Fiberglass Reinforced Thermosetting Resin Pipe, Section III, Division 1 The design temperature for spray pond piping must be 100°C (212°F). The allowable design stress must be the value obtained from the minimum hydrostatic design basis in Table 3611-1 of Code Case N‑155‑2 (Procedure A or B) or the value determined as one‑sixth of the stress obtained from a short-time burst test for the pipe being qualified, whichever is lower. The short-time burst strength must be determined by bursting the pipe (ASTM D‑1599‑74) using free‑end mounting after it has been exposed to 1x105 pressure cycles from atmospheric to design pressure. The value of “K” in Equation 9 of Paragraph 3652 must be limited to 1.2 unless it can be demonstrated that, with the use of a large value of K1, the functional capability of the system will not be impaired during upset and emergency conditions. RTR piping must be uninsulated or uncovered and installed under conditions that make it readily accessible for inspection. Preoperational and inservice inspections must be as follows: During the preoperational testing period, tests must be made to verify that the piping is free of vibration induced by weather conditions or water flow that could fatigue the piping prematurely. Fiberglass-reinforced piping components must be inspected in accordance with ASME Code, Section XI, for Code Class 3 components. In addition, all pipe supports must be inspected. Inspection frequency for piping must be increased to once annually if an exterior weather‑resistant coating is not provided.	2/11/16
N-160 (1797)	Finned Tubing for Construction, Section III, Division 1	7/18/85
N-188	Use of Welded Ni-Fe-Cr-Mo-Cu (Alloy 825) and Ni-Cr-Mo-Cb (Alloy 625) Tubing, Section III, Division 1, Class 3	1/1/78
N-192 N-192-1 N-192-2	Use of Flexible Hose for Section III, Division 1, Class 1, 2, and 3 Construction The applicant should indicate the system application, design and operating pressure, and pressure-temperature rating of the flexible hose. Data to demonstrate compliance of the flexible hose with NC/ND-3649, particularly NC-ND-3649.4(e), are required to be furnished with the application.	8/30/79 9/16/81 7/23/02
N-196	Exemption from the Shake-down Requirements When Plastic Analysis is Performed for Section III, Division 1, Class 1 Construction	1/8/79
N-207	Use of Modified SA-479 Type XM-19 for Section III, Division 1, Class 1, 2, or 3 Construction	3/19/79
N-208-1	Fatigue Analysis for Precipitation Hardening Nickel Alloy Bolting Material to Specification SB-637 N07718 for Section III Division 1, Class 1 Construction	2/14/03
N-214 N-214-1	Use of SA-351, Grade CN7M, for Valves for Section III, Division 1, Construction	9/7/82 5/25/83
N-224	Use of ASTM A500 Grade B and ASTM A501 Structural Tubing for Welded Attachments for Section III, Class 2 and 3 Construction	5/11/81
N-237	Hydrostatic Testing of Internal Piping, Section III, Division 1	9/7/82
N-237-1	Hydrostatic Testing of Internal Piping, Section III, Division 1, Classes 2 and 3	5/25/83
N-242	Materials Certification, Section III, Division 1, Classes 1, 2, 3, MC, and CS Construction Applicants should identify the components and supports that require the use of Paragraphs 1.0 through 4.0 of the Code Case in their safety analysis reports.	4/10/80
N-246	Use of SB-169 Alloy CA614, Section III, Division 1, Class 3	9/7/82
N-246-1	SB-169, Alloy C 61400, Section III, Division 1, Class 3	5/25/83
N-249	Additional Materials for Component Supports Fabricated without Welding, Section III, Division 1, Subsection NF, Class 1, 2, 3, and MC Component Supports Footnote 2 of the Code Case should apply to all materials listed in Tables 1, 2, 3, 4, and 5 of the Code Case and should be so indicated on line 5 of the “Reply.”	5/11/81
N-249-1	Additional Materials for Component Supports Fabricated without Welding, Section III, Division 1, Subsection NF, Class 1, 2, 3, and MC Component Supports Paragraph 7 of the “Reply” should reference the requirements in Paragraph NF‑2600 instead of those in Paragraph NF‑2800. This is a typographical error because Paragraph NF‑2800 does not exist.	6/17/82
N-249-2 N-249-3	Additional Materials for Subsection NF Class 1, 2, 3, and MC Component Supports Fabricated without Welding, Section III, Division 1	2/14/83 2/20/84
N-249-4 N-249-5	Additional Material for Subsection NF, Classes 1, 2, 3, and MC Component Supports Fabricated without Welding, Section III, Division 1 The fracture toughness requirements, as listed in Code Case N‑249‑4, apply only to piping supports and not to Classes 1, 2, and 3 component supports. The fracture toughness of Classes 1, 2, and 3 component supports should be characterized in accordance with Section 5.3.4 of NUREG‑0800, “Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition” (SRP) (Ref. 17), or on a case‑by‑case basis.	9/17/84 4/8/85
N-249-6 N-249-7 N-249-8 N-249-9 N-249-10 N-249-11 N-249-12 N-249-13	Additional Material for Subsection NF, Classes 1, 2, 3, and MC Component Supports Fabricated without Welding, Section III, Division 1 The fracture toughness requirements apply only to piping supports and not to Classes 1, 2, and 3 component supports. The fracture toughness of Classes 1, 2, and 3 component supports should be characterized in accordance with SRP Section 5.3.4 (Ref. 17), or on a case-by-case basis. The following should be added to Paragraph 5 of the Code Case: “For these cases, the owner should demonstrate that (1) the impact test results for the material meet Code requirements and (2) the material is not subject to stress‑corrosion cracking because a corrosive environment is not present and because the component that contains the material has essentially no residual stresses or assembly stresses and it does not experience frequent sustained loads in service.”	9/5/85 12/5/85 12/16/86 5/6/89 5/13/91 2/12/93 5/11/94 12/8/00
N-249-14	Additional Materials for Subsection NF, Class 1, 2, 3, and MC Component Supports Fabricated without Welding, Section III, Division 1 The fracture toughness requirements apply only to piping supports, not to Class 1, Class 2, and Class 3 component supports. The following should be added to Paragraph (e) of the Code Case: “For these cases, the owner must demonstrate that (1) the impact test results for the material meet Code requirements and (2) the material is not subject to stress‑corrosion cracking because a corrosive environment is not present and because the component that contains the material has essentially no residual stresses or assembly stresses and it does not experience frequent sustained loads in service.”	2/20/04
N-249-15 N-249-16	Additional Materials for Subsection NF, Classes 1, 2, 3, and MC Supports Fabricated without Welding, Section III, Division 1	7/15/14 4/10/18
N-260	Weld Repair of SA-182 Type 316 Forgings, Section III, Division 1, Classes 1, 2, 3, and MC	7/18/85
N-260-1	Weld Repair of SA-182 Type 316 Forgings, Section III, Division 1, Classes 1, 2, 3, and MC Type 308L welding materials should not be used to repair Grade F 316 N forgings because of the difference in strength levels.	12/5/85
N-265	Modified SA-487 Castings, Section III, Division 1, Class 1	5/19/85
N-284-1	Metal Containment Shell Buckling Design Methods, Section III, Division 1, Class MC This Code Case is listed in RG 1.193.	10/2/00
N-284-2 N-284-3	Metal Containment Shell Buckling Design Methods, Class MC, TC, and SC Construction, Section III, Divisions 1 and 3	1/10/07 12/17/12
N-299	Use of Nickel-Chromium-Molybdenum-Columbium Alloy 625 Forgings, Section III, Division 1, Class 2 and Class 3 Components	7/18/85
N-304 N-304-1 N-304-2 N-304-3	Use of 20 Cr-25Ni-6Mo (Alloy UNS N08366) Welded Tubes for Section III, Division 1, Classes 2 and 3 Construction	7/12/84 5/19/85 12/5/85 2/23/87
N-309	Identification of Materials for Component Supports, Section III, Division 1	5/11/84
N-318 N-318-1 N-318-2 N-318-3 N-318-4	Procedure for Evaluation of the Design of Rectangular Cross Section Attachments on Class 2 or 3 Piping, Section III, Division 1 Applicants should identify the following in their safety analysis report: (1) the method of lug attachment (2) the piping system involved (3) the location in the system where the Code Case will be applied	2/20/84 7/12/84 9/5/85 12/11/89 4/28/94
N-319 N-319-1 N-319-2	Alternate Procedure for Evaluation of Stresses in Butt Weld Elbows in Class 1 Piping, Section III, Division 1	7/24/89 8/14/90 1/17/00
N-321	Use of Modified SA-249, Type 304, Section III, Division 1, Class 1 Construction	12/5/85
N-337	Use of ASTM B 525-70 Grade II, Type II, Sintered Austenitic Stainless Steel for Class 2, 3, and MC Component Standard Supports, Section III, Division 1	7/18/85
N-345	Attachment of AMS 5382 Alloy 31 Seat Rings by Friction Welding, Section III, Division 1, Classes 1, 2, and 3	12/13/82
N-351	Use of Subsize Charpy V-Notch Specimens, Section III, Division 1	10/13/21
N-352	Use of SA-638 Grade 660 Forgings and Bars below 700°F without Stress Rupture Tests, Section III, Division 1	7/18/85
N-362	Alternate Rules for Pressure Testing of Containment Items, Section III, Division 1	12/13/82
N-362-1	Pressure Testing of Containment Items, Section III, Division 1, Classes 1, 2, and MC	7/12/84
N-370 N-370-1	Modified SA-705 Grade XM-13 Forgings, Section III, Division 1	7/18/85 12/5/85
N-371	12Cr-1W-1Mo-1/4V Martensitic Stainless Steel Valve Internals, Section III, Division 1	7/18/85
N-373-1 N-373-2	Alternative PWHT Time at Temperature for P-No. 5 Material, Section III, Division 1, Classes 1, 2, and 3	9/7/01 11/2/04
N-379	Bimetallic Tubing Section III, Division 1, Class 1	7/18/85
N-383	Weld Repair of SA-182 Austenitic Forgings, Section III, Division 1, Classes 1, 2, and 3 Applicants who apply the provisions of the Code Case to permit material manufacturers to weld repair austenitic forgings without resolution heat treatment should justify to the NRC staff (through the safety analysis report) why this is acceptable for their applications, including their evaluation of the susceptibility for stress‑corrosion cracking.	7/18/85
N-391	Procedure for Evaluation of the Design of Hollow Circular Cross Section Welded Attachments on Class 1 Piping, Section III, Division 1	7/24/89
N-391-1	Procedure for Evaluation of the Design of Hollow Circular Cross Section Welded Attachments on Class 1 Piping, Section III, Division 1 The following typographical errors need to be corrected: In Equation 3, the + sign should be changed to an = sign. In Equation 4, the first + sign should be changed to an = sign.	8/24/95
N-392	Procedure for Evaluation of the Design of Hollow Circular Cross Section Welded Attachments on Classes 2 and 3 Piping, Section III, Division 1	12/11/89
N-392-1	Procedure for Evaluation of the Design of Hollow Circular Cross Section Welded Attachments on Classes 2 and 3 Piping, Section III, Division 1 Applicants should identify the following in their safety analysis report: the method of lug attachment the piping system involved the location in the system where the Code Case will be applied	12/11/92
N-392-2	Procedure for Evaluation of the Design of Hollow Circular Cross Section Welded Attachments on Classes 2 and 3 Piping, Section III, Division 1 Applicants should identify in their safety analysis report: the method of lug attachment the piping system involved the location in the system where the Code Case will be applied	12/12/94
N-411	Alternative Damping Values for Seismic Analysis of Classes 1, 2, and 3 Piping Sections, Section III, Division 1 The damping values specified may be used to analyze piping response for seismic and other dynamic loads that are being filtered through building structures provided that the response mode frequencies are limited to 33 hertz and below. Within this range, the Code Case damping should be used completely and consistently, if it is used at all. (For equipment other than piping, the damping values specified in RG 1.61 (Ref. 12), should be used.) The damping values specified may be used only in those analyses in which current seismic spectra and procedures have been employed. Such use should be limited only to response spectral analyses [similar to that used in the study supporting its acceptance, NUREG/CR-3526 (Ref. 13)]. The acceptance of the use with other types of dynamic analyses (e.g., time-history analysis) is pending further justification. When used for reconciliation work or for support optimization of existing designs, the effects of increased motion on existing clearances and online mounted equipment should be checked. This Code Case is not appropriate for analyzing the dynamic response of piping systems that use supports designed to dissipate energy by yielding (i.e., the design of which is covered by Code Case N‑420). (5) This Code Case does not apply to piping in which stress‑corrosion cracking has occurred unless a case‑specific evaluation is made and is reviewed by the NRC staff.	2/20/86
N-418	Use of Seamless Ni-Fe-Cr-Mo-Cu Low Carbon (UNS N08028 and UNS N08904) Tubing, Section III, Division 1, Classes 2 and 3	7/30/86
N-438 N-438-1 N-438-2	Fe-24.5Ni-21Cr-6.5 Mo-0.2N (Alloy UNS N08367) Seamless and Welded Pipe, Tube, Plate, Bar, Fittings, and Forgings, Class 2 and 3 Construction, Section III, Division 1	3/8/89 Reinstated on 5/24/96 7/27/92
N-438-3	UNS N08367 Material, Section III, Division 1, Class 2 and 3 Construction	5/24/96
N-439	Use of 20Cr-18Ni-6Mo (Alloy UNS S31254) Forgings, Plate, Seamless and Welded Pipe, and Welded Tube, Class 2 and 3 Construction, Section III, Division 1	7/10/00
N-440	Use of 20Cr-18Ni-6Mo (Alloy UNS J93254) Castings, Class 2 and 3 Construction, Section III, Division 1	7/10/00
N-441 N-441-1	Use of 20Cr-18Ni-6Mo (Alloy UNS S31254) Fittings, Class 2 and 3 Construction, Section III, Division 1	11/25/92 7/10/00
N-443 N-443-1	High Yield Strength Cr-Mo Steel, Class 1 Components, Section III, Division 1	3/8/89 11/11/99
N-453	Nickel-Chromium-Molybdenum-Copper Stainless Steel (UNS N08925) Welded Pipe for Class 2 and 3 Construction, Section III, Division 1	11/30/88
N-453-1	Nickel-Chromium-Molybdenum-Copper Stainless Steel (UNS N08925) Seamless and Welded Pipe for Class 2 and 3 Construction, Section III, Division 1	4/30/92
N-453-2	Nickel-Chromium-Molybdenum-Copper Stainless Steel (UNS N08925 and N08926) Seamless and Welded Pipe for Class 2 and 3 Construction, Section III, Division 1	12/12/95
N-454	Nickel-Chromium-Molybdenum-Copper Stainless Steel (UNS N08925) Wrought Fittings for Class 2 and 3 Construction, Section III, Division 1	4/30/92
N-455	Nickel-Chromium-Molybdenum-Copper Stainless Steel (UNS N08925) Forged Flanges and Fittings for Class 2 and 3 Construction, Section III, Division 1	4/30/92
N-466	Modified 9Cr-1Mo Material, Section III, Division 1, Classes 1, 2, and 3	4/30/90
N-469	Martensitic Stainless Steel for Class 1, 2, and 3 Components, Section III, Division 1	6/14/00
N-474	Design Stress Intensities and Yield Strength Values for Alloy 690 with a Minimum Yield Strength of 35 ksi, Class 1 Components, Section III, Division 1	3/5/90
N-474-1	Design Stress Intensities and Yield Strength Values for UNS N06690 with a Minimum Specified Yield Strength of 35 ksi, Class 1 Components, Section III, Division 1	12/9/93
N-484	Real Time Radioscopic Examination of Welds, Section III, Division 1	12/16/91
N-492	Grade 9 Titanium Alloy Tubing, Section III, Division 1, Class 1, 2, and 3	5/11/94
N-497	Use of Fe-Ni-Cr-Mo-N (C-N-3MN) Cast Materials, Section III, Division 1, Class 2 and 3 Construction	12/9/93
N-500 N-500-1 N-500-2 N-500-3	Alternative Rules for Standard Supports for Classes 1, 2, 3, and MC, Section III, Division 1	12/9/93 8/14/01 2/20/04 8/5/11
N-510	Borated Stainless Steel for Class CS Core Support Structures and Class 1 Components, Section III, Division 1	12/12/94
N-520 N-520-1 N-520-2 N-520-3 N-520-4 N-520-5	Alternative Rules for Renewal of N-type Certificates for Plants Not in Active Construction, Section III, Division 1	10/26/94 5/9/03 11/1/07 11/10/09 3/13/12 5/18/2012
N-539	UNS N08367 in Class 2 and 3 Valves, Section III, Division 1	8/16/16
N-564 N-564-1	UNS J93380, Alloy CD3MWCuN, Class 2 and 3 Construction, Section III, Division 1	7/30/98 12/31/96
N-570	Alternative Rules for Linear Piping and Linear Standard Supports for Classes 1, 2, 3, and MC, Section, III, Division 1	3/28/06 1/5/06
N-570-1	Alternative Rules for Linear Piping and Linear Standard Supports for Classes 1, 2, 3, and MC, Section III, Division 1 The provisions of ANSI/AISC N690-1994 s2, “Supplement No. 2 to the Specification for the Design, Fabrication, and Erection of Steel of Safety-Related Structures for Nuclear Facilities,” must be met.	1/5/06
N-570-2	Alternative Rules for Linear Piping and Linear Standard Supports for Classes 1, 2, 3, and MC, Section, III, Division 1	1/11/21
N-580 N-580-1	Use of Alloy 600 with Columbium Added, Section III, Division 1	5/26/97 5/20/98
N-594	Repairs to P-4 and P-5A Castings without Postweld Heat Treatment Class 1, 2, and 3 Construction, Section III, Division 1	3/2/98
N-595-3	Requirements for Spent Fuel Storage Canisters, Section III, Division 1 The canisters must be made from austenitic stainless steel Type 304 or 316.	4/8/02
N-621	Ni-Cr-Mo Alloy (UNS N06022) Welded Construction to 800°F, Section III, Division 1	11/2/04
N-625	Ni-Cr-Mo Alloy (UNS N06059) Welded Construction to 800°F, Section III, Division 1	3/28/01
N-635	Use of 22Cr-5Ni-3Mo-N (Alloy UNS S31803) Forgings, Plate, Bar, Welded and Seamless Pipe, and/or Tube, Fittings, and Fusion Welded Pipe with Addition of Filler Metal, Classes 2 and 3, Section III, Division 1	2/14/03
N-637	Use of 44Fe-25Ni-21Cr-Mo (Alloy UNS N08904) Plate, Bar, Fittings, Welded Pipe, and Welded Tube, Classes 2 and 3, Section III, Division 1	9/20/10
N-644	Weld Procedure Qualification for Procedures Exempt from PWHT in Class 1, 2, and 3 Construction, Section III, Division 1	Reinstated 2/14/03
N-655	Use of SA-738, Grade B, for Metal Containment Vessels, Class MC, Section III, Division 1 For metal containment vessels up to 1.75 inches thick, the following requirements apply: (1) Supplementary Requirement S17, “Vacuum Carbon-Deoxidized Steel,” of Material Specification SA-738 must be applied to the material. (2) Supplementary Requirement S20, “Maximum Carbon Equivalent for Weldability,” of Material Specification SA-738 must be applied to the material.	2/25/02
N-692	Use of Standard Welding Procedures, Section III, Division 1	5/9/16
N-755-3	Use of Polyethylene (PE) Class 3 Plastic Pipe, Section III, Division 1	5/11/17
N-757	Alternative Rules for Acceptability for Class 2 and 3 Valves (DN 25) and Smaller with Welded and Nonwelded End Connections Other Than Flanges, Section III, Division 1	1/21/07
N-759 N-759-1	Alternative Rules for Determining Allowable External Pressure and Comprehensive Stresses for Cylinders, Cones, Spheres, and Formed Heads, Class 1, 2, and 3, Section III, Division 1	10/4/06 10/19/07
N-760 N-760-1	Welding of Valve Plugs to Valve Stem Retainers, Classes 1, 2, and 3, Section III, Division 1	3/27/07 2/12/08
N-801 N-801-1 N-801-2	Rules for Repair of N-Stamped Class 1, 2, and 3 Components, Section III, Division 1	8/12/12 5/9/16 5/11/17
N-822 N-822-1 N-822-2 N-822-3	Application of the ASME Certification Mark Section III, Divisions 1, 2, 3, and 5	12/6/11 12/17/12 12/28/15 8/2/16
N-863	Postweld Heat Treatment (PWHT) of Valve Seal Welds for P4 and P5A Materials, Section III, Division 1	2/16/17
N-870	Rules for the Elimination of External Surface Defects on Class 1, 2, and 3 Piping, Pumps, or Valves After Component Stamping and Prior to Completion of the N-3 Data Report, Section III, Division 1	11/2/17
1332-6	Requirements for Steel Forgings, Section III, Division 1	3/1/79
1335-9	Requirements for Bolting Materials	8/28/78
1337-9 1337-10	Special Type 403 Modified Forgings or Bars, Section III	4/28/75 5/15/78
1395-3	SA-508, Class 2 Forgings with Modified Manganese Content, Section III or Section VIII, Division 2	1/8/79
1407-2	Time of Examination for Class 1, 2, and 3, Section III Vessels	7/1/74
1414-3 1414-4	High Yield Strength Cr-Mo Steel for Section III, Division 1, Class 1 Vessels Each referencing safety analysis report should provide the information required by Note 1 in the Code Case.	3/1/76 8/9/77
1484-1	SB-163 Nickel-Chromium-Iron Tubing (Alloy 600) at a Specified Minimum Yield Strength of 40.0 ksi, Section III, Class 1	11/4/74
1484-2	SB-163 Nickel-Chromium-Iron Tubing (Alloy 600 and 690) at a Specified Minimum Yield Strength of 40.0 ksi, Section III, Class 1	8/13/76
1492	Post Weld Heat Treatment, Section I, III, and VIII, Division 1 and 2	3/3/75
1508	Allowable Stresses, Design Intensity and/or Yield Strength Values, Section I, III, and VIII, Divisions 1 and 2	6/30/75
1516-1	Welding of Seats in Valves for Section III Applications	8/11/75
1540-1	Elastomer Diaphragm Valves, Section III, Classes 2 and 3	1/14/77
1541-1	Hydrostatic Testing of Embedded Class 2 and Class 3 Piping for Section III Construction	9/30/76
1541-2	Hydrostatic Testing of Embedded Class 2 and Class 3 Piping for Section III, Division 1 Construction	5/15/78
1552	Design by Analysis of Section III, Class 1 Valves	8/29/77
1553	Upset Heading and Roll Threading of SA-453 for Bolting in Section III	3/3/75
1555	Certification of Safety Relief Valves on Liquids	1/14/77
1557-2	Steel Products Refined by Secondary Remelting	1/8/79
1606	Stress Criteria for Section III, Class 2 and 3 Piping Subjected to Upset, Emergency, and Faulted Operating Conditions Code Case 1606 was acceptable subject to the interpretation that the stress limit designations of “Upset,” “Emergency,” and “Faulted” do not necessarily imply agreement with specified plant conditions that apply to ASME Code Class 2 and 3 components for fluid systems. The design specifications should establish and justify these designations.	12/16/74
1607	Stress Criteria for Section III, Classes 2 and 3 Vessels Subjected to Upset, Emergency, and Faulted Operating Conditions Code Case 1607 was acceptable subject to the interpretation that the stress limit designations of “Upset,” “Emergency,” and “Faulted” do not necessarily imply agreement with specified plant conditions that apply to ASME Code Class 2 and 3 components for fluid systems. The design specifications should establish and justify these designations.	11/4/74
1618	Material for Core Support Structures, Section III, Subsection NG (1) Welding of age-hardenable Alloy SA-453 Grade 660 and SA‑637 Grade 688 should be performed when the material is in a solution‑treated condition. (2) Use of alloy ASTM A‑564 Grade 631 is not acceptable on a generic basis.	3/3/75
1618-1	Material for Core Support Structures, Section III, Subsection NG Welding of age-hardenable alloy SA-453 Grade 660 and SA‑637 Grade 688 should be performed when the material is in a solution‑treated condition.	3/1/76
1626	Normalized and Tempered 1-1/4 Cr Low Alloy Steel Forgings, Section I, Section III, and Section VIII, Division 1 and 2	1/8/79
1634 1634-1	Use of SB-359 for Section III, Class 3 Construction	8/12/74 8/13/76
1644 1644-1 1644-2 1644-3	Additional Materials for Component Supports, Section III, Subsection NF, Class 1, 2, 3, and MC Construction The maximum measured UTS of the component support material should not exceed 170 ksi.	4/28/75 6/30/75 11/3/75 3/1/76
1644-4 1644-5 1644-6	Additional Materials for Component Supports and Alternate Design Requirements for Bolted Joints, Section III, Division 1, Subsection NF, Class 1, 2, 3, and MC Construction The maximum measured UTS of the component support material should not exceed 170 ksi because of the susceptibility of high‑strength materials to brittleness and stress‑corrosion cracking. Certain applications may exist where a UTS value of up to 190‑ksi could be considered acceptable for a material; under this condition, the design specification should specify impact testing for the material. For these cases, the applicant should demonstrate that (1) the impact test results for the material meet Code requirements and (2) the material is not subject to stress‑corrosion cracking because a corrosive environment is not present and because the component that contains the material has essentially no residual stresses or assembly stresses and it does not experience frequent sustained loads in service.	8/13/76 3/3/77 11/21/77
1682	Alternate Rules for Material Manufacturers and Suppliers, Section III, Subarticle NA-3700	8/11/75
1683	Bolt Holes for Section III, Division 1, Class 1, 2, 3 and MC Component Supports	3/1/76
1689	Alternate PWHT Time and Temperature for SA-182 Grade F22, Section III, Class 1, 2, 3 and CS The alternate PWHT should be prequalified along with the applicable welding procedure in accordance with Section IX.	9/10/76
1695	Brazing, Section III, Class 3	11/3/75
1701	Determination of Capacities of Vacuum Relief Valves, Section III, Class MC	3/20/78
1702	Flanged Valves Larger than 24 Inches for Section III, Class 1, 2 and 3 Construction	7/11/77
1714	Postweld Heat Treatment of P-1 Material, Section III, Class MC	7/11/77
1720	Weld End Preparation for Section III, Division Construction Weld end preparations other than those shown in Figures 1, 2, and 3 of the Code Case are not acceptable on a generic basis. Such alternative end preparations should be treated on a case-by-case basis.	3/1/76
1720-1	Weld End Preparation for Section III, Division Construction The acceptance of weld end preparations other than those shown in Figures 1, 2, and 3 of the Code Case should be evaluated on a case‑by‑case basis.	11/20/78
1722	Vacuum, Carbon Deoxidized SA-508 Forgings, Section III, Division 1, and VIII, Division 1 and 2	1/8/79
1741	Interim Rules for the Required Number of Impact Tests for Rolled Shapes, Section III, Division 1, Subsection NF, Component Supports	1/14/77
1755	Alternate Rules for Examination of Welds in Piping, Class 1 and 2 Construction, Section III, Division 1	1/14/77
1759	Material for Internal Pressure Retaining Items for Pressure Relief Valves, Section III, Division 1, Class 1, 2, and 3 Applicants using this Code Case should also use Code Case 1711 for the design of pressure relief valves.	5/15/78
1761	Use of SG-148 Alloy CA954 for Section III, Division 1, Class 2 or 3 Flanged End Valves	1/14/77
1769	Qualification of NDE Level III Personnel, Section III, Division 1	2/16/77
1774	Minimum Wall Thickness for Class 2 and 3 Valves, Section III, Division 1	7/11/77
1780	Hydrostatic Testing and Stamping of Pumps for Class 1 Construction, Section III, Division 1 Each licensing application in which the Code Case is to be used should present information that satisfactorily demonstrates that the subassembly tests adequately simulate the pressure loadings. In addition, the closure fixture for the test subassembly should adequately simulate the rigidity of adjacent subassemblies and also simulate the interface loadings from adjacent subassemblies that would result from a hydrostatic pressure test of a complete pump assembly. As a minimum, the closure fixture should impose loads that result in stresses equal to or greater than those induced during the hydrostatic test of a complete pump assembly. Hydrostatic testing should not simulate piping reactor loadings.	3/10/78
1783	Qualification of Nondestructive Personnel, Section III, Division 1 The first sentence of Paragraph 1 of the Code Case should be replaced with the following: “The certification of the Level III nondestructive examination personnel for the purposes of this Section of the Code shall be the responsibility of the employer of the Level III individual. If the employer is not a Certificate Holder, then the verification of such certificate is the responsibility of the Certificate Holder.”	1/14/77

D. IMPLEMENTATION

The purpose of this section is to provide information to applicants and licensees regarding the NRC staff’s plans for using this regulatory guide. This regulatory guide lists the ASME BPV Code, Section III Code Cases that the NRC has approved for use as voluntary alternatives to the mandatory ASME BPV Code provisions that are incorporated by reference into 50.55a. The requirements addressing implementation of Section III Code Cases are contained in 10 CFR 50.55a(b)(4). An applicant’s or a licensee’s voluntary application of an approved Code Case does not constitute backfitting, inasmuch as there is no imposition of a new requirement or new position. No backfitting is intended or approved in connection with the issuance of this guide.

REFERENCES¹

1. American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, Section III, “Rules for Construction of Nuclear Power Plant Components,” Division 1, New York, NY.¹

2. Code of Federal Regulations (CFR), “Domestic Licensing of Production and Utilization Facilities” Part 50, Chapter 1, Title 10, “Energy.”

3. CFR, “Licenses, Certifications, and Approvals for Nuclear Power Plants,” Part 52, Chapter 1, Title 10, “Energy.”

4. U.S. Nuclear Regulatory Commission (NRC) Regulatory Guide (RG) 1.147, “Inservice Inspection Code Case Acceptability, ASME Section XI, Division 1,” Washington, DC.

5. NRC, RG 1.192, “Operation and Maintenance Code Case Acceptability, ASME OM Code,” Washington, DC.

6. NRC, RG 1.193, “ASME Code Cases Not Approved for Use,” Washington, DC.

7. NRC, RG 1.136, “Design Limits, Loading Combinations, Materials, Construction, and Testing of Concrete Containments,” Washington, DC.

8. NRC, RG 1.87, “Acceptability of ASME Code, Section III, Division 5 High Temperature Reactors,” Washington, DC.

9. American Society for Testing and Materials International (ASTM) A 262‑70, “Standard Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels,” West Conshohocken, PA.¹

10. ASTM A 708-74, “Practice for Detection of Susceptibility to Intergranular Corrosion in Severely Sensitized Austenitic Stainless Steels,” West Conshohocken, PA.

11. NRC, RG 1.122, “Development of Floor Design Response Spectra for Seismic Design of Floor‑Supported Equipment or Components,” Washington, DC.

12. NRC, RG 1.61, “Damping Values for Seismic Design of Nuclear Power Plants,” Washington, DC.

13. NUREG/CR-3526, “Impact of Changes in Damping and Spectrum Peak Broadening on the Seismic Response of Piping Systems,” Washington, DC, March 1984. (ADAMS Accession No. ML20088A672)

14. NRC, RG 1.31, “Control of Ferrite Content in Stainless Steel Weld Metal,” Washington, DC.

15. NRC, RG 1.44, “Control of the Use of Sensitized Stainless Steel,” Washington, DC.

16. NRC, RG 1.67, “Installation of Over-Pressure Protection Devices,” Washington, DC.

17. NRC, NUREG-0800, “Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition,” Washington, DC.

APPENDIX A

SUPPLEMENTS ADDRESSED IN REVISION 40

OF REGULATORY GUIDE 1.84

EDITION	SUPPLEMENT NUMBER	NUMERICAL LISTING OF SECTION III CODE CASES IN SUPPLEMENT
2019	2	None
2019	3	N-290-31, N-900
2019	4	N-861-11, N-862-11, N-893, N-8981, N-901
2019	5	N-902
2019	6	N-904, N-905
2019	7	N-9072, N-908, N-910
2021	0	N-71-21, N-570-3, N-707-23, N-903
2021	1	N-9152, N-9162
2021	2	N-919, N-920
2021	3	N-755-44, N-351-1

Code Case Number	Approval Date	Table Where Code Case Is Listed
N-4-13	2/12/08	Table 1
N-60-6	12/6/11	Table 1
N-62-7	2/3/03	Table 2
N-71-21	1/11/21	Table 2
N-131-1	2/3/03	Table1
N-133-3	2/3/03	Table 1
N-154-1	2/3/03	Table 1
N-155-3	2/11/16	Table 2
N-205	2/25/02	Table 1
N-213-1	2/11/16	RG 1.136
N-249-17	4/10/18	Table 1
N-258-2	3/28/01	RG 1.136
N-284-4	10/8/12	Table 1
N-290-3	10/6/19	Division 5
N-312	3/28/01	RG 1.136
N-315	2/3/03	Table 1
N-319-3	2/3/03	Table 1
N-351-1	10/13/21	Table 1
N-369	5/9/03	Table 1
N-373-3	10/8/04	Table 1
N-405-1	2/20/04	Table 1
N-452	5/9/03	Table 1
N-453-3	8/14/01	Table 1
N-454-1	6/17/03	Table 1
N-455-1	7/17/03	Table 1
N-469-1	2/3/03	Table 1
N-500-4	10/14/11	Table 1
N-505	5/4/04	Table 1
N-511	5/4/04	Table 1
N-519-1	1/16/19	RG 1.193
N-520-6	12/11/12	Table 1
N-525	7/23/02	Table 1
N-530	2/3/03	RG 1.193
N-539-1	8/16/16	Table 1
N-548	9/7/01	Table 1
N-564-2	2/3/03	Table 1
N-565	12/3/99	RG 1.193
N-570-3	1/11/21	Table 2
N-579	2/3/03	Table 1
N-580-2	1/4/08	Table 1
N-594-1	10/14/11	Table 1
N-607	5/4/04	Table 1
N-610	5/4/04	Table 1
N-620	5/4/04	Table 1
N-621-1	10/8/04	Table 1
N-625-1	2/20/04	Table 1
N-631	7/23/02	Table 1
N-632	2/3/03	RG 1.136
N-633	6/14/02	RG 1.136
N-635-1	2/14/03	Table 1
N-636	7/23/02	Table 1
N-637-1	9/20/10	Table 1
N-642	2/3/03	Table 1
N-644-1	3/28/01	Table 1
N-650	2/20/04	Table 1
N-655-2	6/6/10	Table 1
N-659-3	10/12/17	RG 1.193
N-673	8/7/03	RG 1.193
N-692-1	5/9/16	Table 1
N-698	11/18/03	Table 1
N-699	1/5/06	Table 1
N-703	5/4/04	Table 1
N-707-2	1/11/21	Division 3
N-708	9/21/08	Table 1
N-710	5/4/04	Table 1
N-721-1	10/20/16	Table 1
N-725	1/12/05	Table 1
N-727	2/24/06	Table 1
N-736	1/5/06	Table 1
N-738	7/1/05	Table 1
N-741	10/11/05	Table 1
N-746	1/5/06	Table 1
N-748	9/9/08	Division 3
N-756	1/21/07	Table 1
N-757-1	9/21/07	Table 2
N-759-2	1/4/08	Table 1
N-760-2	10/10/08	Table 1
N-761	9/20/10	RG 1.193
N-763	8/28/08	RG 1.136
N-767	1/4/08	Table 1
N-774	9/3/08	Table 1
N-777	10/10/08	Table 1
N-779	1/26/09	Table 2
N-782	1/30/09	Table 1
N-785	10/12/09	Table 1
N-791	9/20/10	RG 1.136
N-792-1	8/12/12	RG 1.193
N-793	9/20/10	RG 1.136
N-794	9/20/10	RG 1.136
N-796	10/18/10	RG 1.136
N-801-3	5/11/17	Table 1
N-804	10/14/11	RG 1.193
N-807	4/20/11	RG 1.136
N-811	8/5/11	RG 1.136
N-812-1	1/10/13	Division 5
N-815	12/6/11	Table 1
N-816	12/6/11	Table 1
N-817	12/6/11	Table 1
N-818-1	8/20/14	RG 1.193
N-819	12/6/11	Table 1
N-820	12/29/11	RG 1.136
N-822-4	8/2/16	Table 1
N-833	1/2/13	RG 1.136
N-834	10/22/13	Table 1
N-836	10/22/13	Table 1
N-837	10/22/13	RG 1.193
N-841	1/6/14	Table 1
N-844	2/9/14	Table 1
N-846	7/25/14	RG 1.193
N-850	10/20/14	RG 1.136
N-852	2/9/15	Table 2
N-855	7/8/15	Table 1
N-856	7/16/15	Table 1
N-859	1/20/16	Table 1
N-861-1	12/2/19	Division 5
N-862-1	12/2/19	Division 5
N-863-1	2/16/17	Table 1
N-866	11/14/16	Table 1
N-870-1	11/2/17	Table 1
N-872	10/20/16	Division 5
N-879	5/10/17	Table 1
N-881	12/4/17	RG 1.193
N-883	1/29/18	Table 2
N-884	10/23/18	Table 1
N-886	5/2/18	Table 2
N-887	5/2/18	Table 1
N-891	12/17/18	Table 1
N-893	12/21/19	Table 1
N-898	10/6/19	Division 5
N-900	7/29/19	Table 1
N-901	12/21/19	Table 1
N-902	2/20/20	Table 1
N-903	4/28/20	Division 5
N-904	5/27/20	Table 1
N-905	5/27/20	Table 1
N-907	8/14/20	RG 1.193
N-908	9/2/20	Table 1
N-910	9/2/20	Table 1
N-915	5/7/21	RG 1.193
N-916	5/7/21	RG 1.193
N-919	8/23/21	Table 1
N-920	8/10/21	Table 1

1 ASME Section III, Division 2 Code Cases are addressed in RG 1.136. Code Cases that pertain to Section III, Division 3 and Division 5 are addressed in new RGs currently under development.

1 Publicly available NRC published documents are available electronically through the NRC Library on the NRC’s public Web site at http://www.nrc.gov/reading-rm/doc-collections/ and through the NRC’s Agencywide Documents Access and Management System (ADAMS) at http://www.nrc.gov/reading-rm/adams.html. The documents can also be viewed online or printed for a fee in the NRC’s Public Document Room (PDR) at 11555 Rockville Pike, Rockville, MD. For problems with ADAMS, contact the PDR staff at (301) 415-4737 or (800) 397-4209; fax (301) 415-3548; or e‑mail pdr.resource@nrc.gov. 

1Copies of American Society of Mechanical Engineers (ASME) standards may be purchased from ASME, Two Park Avenue, New York, NY 10016-5990; telephone (800) 843-2763. Purchase information is available through the ASME Web-based store at https://www.asme.org/publications-submissions/publishing-information.

1Copies of American Society for Testing and Materials International (ASTM) standards may be purchased from ASTM, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428‑2959; telephone (610) 832-9585. Purchase information is available through the ASTM Web site at http://www.astm.org.

.

1 This is a Division 5 Code Case and is not addressed in this RG.

2 This Code Case is not acceptable for use (See RG 1.193)

3 This is a Division 3 Code Case and is not addressed in this RG.

4 Annulled

This RG is being issued in draft form to involve the public in the development of regulatory guidance in this area. It has not received final staff review or approval and does not represent an NRC final staff position. Public comments are being solicited on this DG and its associated regulatory analysis. Comments should be accompanied by appropriate supporting data. Comments may be submitted through the Federal rulemaking Web site, http://www.regulations.gov, by searching for draft regulatory guide DG-1405. Alternatively, comments may be submitted to Office of the Secretary, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, ATTN: Rulemakings and Adjudications Staff. Comments must be submitted by the date indicated in the Federal Register notice.

Electronic copies of this DG, previous versions of this guide, and other recently issued guides are available through the NRC’s public Web site under the Regulatory Guides document collection of the NRC Library at https://nrcweb.nrc.gov/reading-rm/doc-collections/reg-guides/. The DG is also available through the NRC’s Agencywide Documents Access and Management System (ADAMS) at http://www.nrc.gov/reading-rm/adams.html, under Accession No. ML22195A282. The regulatory analysis is associated with rulemaking and may be found in ADAMS under Accession No. ML22243A006.