INTERPRETATION 07-16

Subject: Requirement for Repair / Alteration Plan

Edition: 2007

Question 1: Is the "R" Certificate Holder required to prepare a detailed repair plan (Part 3, 3.3.5.2) or an alteration plan (Part 3 ,4.4.1) covering the scope of work prior to commencement of any work for a Section VIII, Div. 2 or Div. 3 vessel?

Reply 1: Yes

Question 2: Is the "R" Certificate Holder required to have the detailed repair plan or alteration plan reviewed and certified by an Engineer meeting the criteria of ASME Section VIII, Div. 2 or 3 prior to commencing any of the work?

Reply 2: Yes

INTERPRETATION 07-15

Subject: Average Pitch

Edition: 2007

Addendum: 2008

Question: Could average pitch be used instead of maximum pitch?

Reply: No

INTERPRETATION 07-14

Subject: Replacement of Pressure Retaining Parts

Edition: 2007

Addendum: 2009

Question: Does the example of a repair given in Part 3, 3.3.3 s), for replacement of a pressure retaining part with a material of different nominal composition and equal or greater allowable stress from that used in the original design, apply to use of the same material when later editions/addenda of the original code of construction permit higher allowable stresses?

Reply: Yes, provided the minimum required thickness is at least equal to the thickness stated on the Manufacturer’s Data Report.

INTERPRETATION 07-13

Subject: The Original Code of Construction

Edition: 2007

Addendum: 2009

Question: When the NBIC references “the original code of construction”, is it required to use the original edition and addenda of that code as was referenced during the item’s original construction?

Reply: No. See Interpretation 95-19.

INTERPRETATION 07-12

Subject: Replacement of Heads with Different Types

Edition: 2007

Addendum: 2009

Question: Does a replacing a flat head/end plate with a hemispherical/elliptical head or vice versa represent a change in contour reflected in the “Examples of Alterations” found in Part 3, 3.4.3 d)?

Reply: Yes.

INTERPRETATION 07-11

Subject: Replacement Parts

Edition: 2007

Addendum: 2010

Question 1: Is it required that a replacement part to be added by welding to an existing pressure retaining component be supported by a Certificate of Compliance from the Fabricator, when the Fabricator is not the installer of the part, and when the new part is a pipe stub with machined weld prep?

Reply 1: No. Replacement parts furnished in compliance with Part 3, 3.2.2 a) are supplied as material and do not need a Certificate of Compliance.

Question 2: Is a Certificate of Compliance required for a replacement part under the conditions described in Question 1, where fabrication consists of cutting a tube to length and/or bending of a tube?

Reply 2: No.

Question 3: Is a Certificate of Compliance required to be provided by the Fabricator when a replacement part furnished in compliance with Part 3, 3.2.2 a) is to be used in an alteration?

Reply 3: No.

INTERPRETATION 07-10

Subject: Routine Repairs

Edition: 2007

Addendum: 2009

Question: Is it the intent of the NBIC that weld build-up of a damaged gasket surface on a flange where neither PWHT nor NDT is required by the code of construction considered a routine repair?

Reply: Yes, provided the “R” Certificate Holder’s quality system program describes the process for identifying, controlling and implementing routine repairs.

INTERPRETATION 07-09

Subject: Schedule 80 Pipe in External Piping

Edition: 2007

Addendum: 2008

Question: As referenced in Part 2, S2.9 b), is a minimum of schedule 80 pipe required for boiler pressure piping beyond the first stop valve from the boiler?

Reply: No, but it is recommended that a minimum of schedule 80 be used for all external piping.

INTERPRETATION 07-08

Subject: Handhole Replacement with Flush Patch

Edition: 2007

Addendum: 2009

Question: Is replacement of an original handhole opening on a ASME Section IV boiler with a flush patch containing a welded coupling considered an alteration?

Reply: Yes, in accordance with 3.4.3 c).

INTERPRETATION 07-07

Subject: Weld Buildup of Wasted Area / Routine Repair

Edition: 2007

Addendum: 2009

Question: May external weld buildup of a wasted area on a pressure retaining item using repair method 3.3.4.3 e) be considered a routine repair?

Reply: No.

INTERPRETATION 07-06

Subject: Replacement Parts for Repairs and Alterations

Edition: 2007

Question: Is it permissible for pressure parts having been in service from one pressure retaining item to be installed in another pressure retaining item as a replacement part for a repair or alteration?

Reply: Yes, provided the pressure parts are installed in accordance with the requirements of the NBIC, and if applicable, with concurrence from the Jurisdiction.

INTERPRETATION 07-05

Subject: Change-Over Valve Permitted in ASME Code Case-2254 Use

Edition: 2007

Addendum: 2008

Question: Is a change-over valve as specified in ASME Code Case-2254 permitted for use between a boiler and the required pressure relief valve?

Reply: Yes, provided the change-over valve meets the requirements of ASME Code Case-2254 and NBIC, Part 2, paragraph 2.5.4 i), and is acceptable to the Jurisdiction.

INTERPRETATION 07-04

Subject: Installation of New Rupture Disc in an Existing Holder

Edition: 2007

Question: Is it permitted to install a new Code stamped/certified rupture disc into an existing disc holder?

Reply: Yes, provided the disc and holder are produced by the same manufacturer, and the holder design is the same as the certified holder for the new rupture disc.

INTERPRETATION 07-03

Subject: Use of Alternative Welding Method 2 on P-No 4 and P-No 5A Base Material

Edition: 2007

Question: Is it the intent of the NBIC to prohibit using Alternative Welding Method 2 on P-No 4 and P-No 5A base materials that are referenced in subsection 2.5.3.2 paragraph d) 3) to subsection 2.5.3.4 paragraph a) in Alternative Welding Method 4 where notch toughness testing was required by the original code of construction?

Reply: No, the reference to 2.5.3.4 a) pertains to repair depth, preheat and interpass temperature limitations.

INTERPRETATION 07-02

Subject: NBIC Manual Requirements for "R", "VR", and "NR" Stamp Holders

Edition: 2007

Question: In subsections 1.6.2, 1.7.5.4, and 1.8.2, it states that "R," "VR" and "NR"certificate holders must have the current edition and addenda of the National Board Inspection Code. Does that statement mean certificate holders must have Parts 1, 2, and 3 of the National Board Inspection Code?

Reply: Yes

INTERPRETATION 07-01

Subject: "Try Testing" of Pressure Relief Valves

Edition: 2004

Addendum: 2006

Question 1: Must pressure relief valves be tested for set or opening pressure and reclosing pressures if a "try test" is performed as permitted by the fourth paragraph of RB-8400?

Reply 1: No.

Question 2: Does the paragraph allowing "try testing" as an alternative to a pressure test eliminate the requirement to test valves with either the system fluid or the fluids specified for testing other than on the system fluid?

Reply 2: No.

Question 3: Does the paragraph in RB-8400 permitting "try testing" as an alternative to a pressure test alter the recommendations in RB-8410?

Reply 3: No.

INTERPRETATION 04-23

Subject: Jurisdictional Acceptance of NDE

Edition: 2004

Addendum: 2005

Question 1: Does RC-1110 specifically require acceptance of the jurisdiction for alternative NDE methods acceptable to the inspector when NDE in accordance with the original code of construction of the pressure retaining item is deemed not possible or practicable?

Reply 1: Yes, where required by the jurisdiction.

Question 2: Does RC-2050(c) specifically require acceptance of the jurisdiction for the examinations and tests to be used in accordance with the requirements of RC-2051?

Reply 2: Yes, where required by the jurisdiction.

Question 3: Does RC-3030(c) specifically require acceptance of the jurisdiction for examination and tests to be used in accordance with the requirements of RC-3031?

Reply 3: Yes, where required by the jurisdiction.

Question 4: Does RC-3031(e) specifically require acceptance of the jurisdiction for nondestructive examination (NDE)?

Reply 4: Yes, where required by the jurisdiction.

INTERPRETATION 04-22

Subject: Inspector Verification of NDE Performed

Edition: 2004

Question: May the inspector ensure that the required nondestructive examinations (NDE) have been performed satisfactorily by reviewing NDE reports?

Reply: Yes.

INTERPRETATION 04-21

Subject: Inspector Involvement in NDE in Lieu of Pressure Test

Edition: 2004

Addendum: 2005

Question: When nondestructive examination is used as an alternative to a pressure test, is the inspector required to witness the nondestructive examination as it is being performed?

Reply: No.

INTERPRETATION 04-20

Subject: Pneumatic Test in Lieu of Liquid Pressure Test

Edition: 2004

Addendum: 2005

Question: Is a pneumatic test as addressed in RC-2051(b) and RC-3031(b) permitted to be used in lieu of a liquid pressure test when pneumatic testing is not addressed by the original Code of Construction?

Reply: Yes.

INTERPRETATION 04-19

Subject: Repair of Threaded Bolt Holes

Edition: 2004

Addendum: 2005

Question 1: Is the welded repair of threaded holes in a studding outlet prohibited under the provisions of RD-2020?

Reply 1: No.

Question 2: May an "R" stamp holder repair threaded bolt holes of a studding outlet by welding and rethreading to the original size?

Reply 2: Yes, as long as all the requirements of the NBIC are met.

Question 3: Is the repair of threaded bolt holes in studding outlets through the use of a helical coil screw threaded insert covered under the NBIC?

Reply 3: No, mechanical repairs are not addressed by the NBIC.

INTERPRETATION 04-18

Subject: Re-rating Using a Later Edition/Addenda of The Original Code of Construction

Edition: 2004

Addendum: 2005

Question: Using the rules of RD-3010, is re-rating of a pressure-retaining item designed by a proof test method permitted using a later edition/addendum of the original Code of Construction?

Reply: Yes, except as may be limited by Code of Construction requirements for satisfactory assurance of accuracy in computing the maximum allowable working pressure. This would include, for example, that all pressure boundary parts be inspected to ensure that each part's current thickness is greater or equal to the minimum or nominal thicknesses as listed on the Manufacturer's Data Report.

INTERPRETATION 04-17

Subject: Procedures for Repairing Cracks and Crack Classification

Edition: 2001

Addendum: 2003

Question 1: Is the procedure for making holes to stop cracks acceptable or endorsed by the NBIC?

Reply 1: A procedure for making holes in a pressure retaining item to stop existing cracks is not addressed by the NBIC.

Question 2: May a crack be classified as a minor defect?

Reply 2: The NBIC does not define the term "minor defect." Defects should be examined to determine the extent of the defect and whether repair by welding is required.

INTERPRETATION 04-16

Subject: "NR" Certificate Interface with Owner's Repair/Replacement Program

Edition: 2004

Question: Is it permissible for an "NR" Certificate Holder to accept material, items, and services from an owner for repair/replacement activities at the owner's facility without placing the owner on the "NR" Certificate Holder's Approved Suppliers List when the material, items, and services were procured and accepted in accordance with the owner's Quality Program (e.g., 10 CFR-50 Appendix B or ASME/ANSI NQA-1)?

Reply: No.

INTERPRETATION 04-15

Subject: Utilizing a Flush Patch to Gain Access Window in Pressure Retaining Items

Edition: 2004

Question: Does the NBIC prohibit making a tube to header weld from the inside of the header by cutting an access "window" in the header, making the tube to header weld, and repairing the header utilizing a flush patch?

Reply: No.

INTERPRETATION 04-14

Subject: Replacement Safety Valves with Different Capacities and Set Pressures than Boiler Data Report

Edition: 2004

Question: Is the replacement of a safety valve or valves where the new safety valve set pressure or capacity is different from the information contained on the boiler data report an alteration?

Reply: No, provided the replacement valve meets the overpressure protection requirements of the original code of construction.

INTERPRETATION 04-13

Subject: Replacement of a Cast Iron Section

Edition: 2004

Question: Is the replacement of an ASME "H" stamped cast iron section classified as a mechanical repair?

Reply: The NBIC does not address this type of repair.

INTERPRETATION 04-12

Subject: Post Weld Heat Treatment of Parts

Edition: 2001

Addendum: 2003

Question: Does an ASME part fabricated using the alternative welding method described in RD-1030, in lieu of Post Weld Heat Treatment required by the original code of construction, satisfy the requirements of RC-1050(c) for replacement parts?

Reply: No. Welded parts must meet the Post Weld Heat Treatment requirements of the original code of construction.

INTERPRETATION 04-11

Subject: Requirements for Testing Replacement Parts

Edition: 2001

Addendum: 2003

Question 1: When a replacement part is supplied by an "S" part manufacturer in accordance with RC-1050(c) without an original construction code pressure testing, must an examination or test on the part be performed in accordance with RC-2051?

Reply 1: Yes.

Question 2: Is it the responsibility of the "R" stamp holder to verify that the requirements of the original code of construction or the alternative examination or test as described in RC-2051 have been performed?

Reply 2: Yes.

INTERPRETATION 04-10

Subject: Flush Patches in Pipes and Tubes NPS 5 or less

Edition: 2004

Question: May the installation of a flush patch to boiler tubes or pipes NPS 5 (DN 125) and smaller, where neither post weld heat treatment nor NDE other than visual examination is required by the original code of construction, be considered a routine repair?

Reply: Yes.

INTERPRETATION 04-09

Subject: Routine Repairs

Edition: 2004

Question: May repairs that are not included in RC-2031(a) be performed and documented as routine repairs?

Reply: No.

INTERPRETATION 04-08

Subject: Fabricated Replacement Critical Parts

Edition: 2004

Question: Do replacement critical parts fabricated to a specification derived from the examination of parts fabricated by the valve manufacturer and a review of documents available in the public domain meet the requirements of RE-1050?

Reply: No.

INTERPRETATION 04-07

Subject: Source for Critical Parts

Edition: 2004

Question: Do the requirements of NBIC, paragraph RE-1050, demand that critical parts be purchased directly from the valve manufacturer or their authorized representative?

Reply: No.

INTERPRETATION 04-06

Subject: Written Procedure Requirements for Non-Destructive Examinations

Edition: 2004

Question: When performing nondestructive examinations listed in RC-2051(e) and RC-3030(c), are written procedures and appropriately qualified personnel required?

Reply: Yes, when required by the original code of construction.

INTERPRETATION 04-05

Subject: "R" Stamp Holder Installation of Code Manufacturer Supplied Parts

Edition: 2001

Addendum: 2003

Question: When a replacement part is supplied by an "S" part manufacturer in accordance with RC-1050(c), without a pressure test in accordance with the original code of construction, may the "R" stamp holder install the part following the requirements of RC-2050 for the part's welds and attachment welds?

Reply: Yes.

INTERPRETATION 04-04

Subject: Re-rating of Pressure-Retaining Items for Lethal Service/Removal of Insulation

Edition: 2004

Question: When re-rating a pressure-retaining item for lethal service, is it required to have the paint, lining, or other coverings removed prior to the pressure test when required by the original code of construction?

Reply: Yes.

INTERPRETATION 04-03

Subject: Re-rating of Pressure-Retaining Items/Removal of Insulation

Edition: 2004

Question: When re-rating a pressure retaining item, is it a requirement that insulation or refractory be removed prior to the pressure test?

Reply: Yes. A sufficient amount of refractory or insulation, as determined by the inspector, shall be removed to allow the inspector to perform a visual inspection of the pressure-retaining item.

INTERPRETATION 04-02

Subject: "VR" Certificate Holder Verification of Manufacturer's Nameplate Capacity

Edition: 2004

Question: Does paragraph RA-2213 require a "VR" Certificate holder to verify that the manufacturer's nameplate capacity is correct in the process of repairing a Code stamped valve?

Reply: Yes, "condition" in RA-2213 includes nameplate information as well as physical condition of the valve.

INTERPRETATION 04-01

Subject: Use of Welded Encapsulation Box in Lieu of Weld Build Up or Flush Patch

Edition: 2004

Question: Does the NBIC prohibit the use of welded encapsulation box as an alteration method to encapsulate a local thin area on a pressure-retaining item in lieu of using weld metal build up or a flush patch?

Reply: No, however, repair of alteration methods other than those addressed in the NBIC shall be acceptable to the inspector and the jurisdiction.

INTERPRETATION 01-41

Subject: Alteration Increasing Boiler Heating Surface & Stamping

Edition: 2001

Addendum: 2003

Question: In the event of an alteration to a boiler in which the boiler heating surface and steaming capacity is increased, is the new heating surface or new steaming capacity of this boiler required to be stamped on the new nameplate, boiler or R-2 form?

Reply: No, however, the exact scope of work must be included in Form R-2, which should include the added heating surface and/or steaming capacity.

INTERPRETATION 01-40

Subject: Use of VT when Pressure Test Is Not Practicable

Edition: 2001

Addendum: 2003

Question: If pressure testing is not practicable and if concurrence of the owner, Inspector and jurisdiction is obtained where applicable, may the Visual Testing (VT) NDE method be used to satisfy the NBIC requirement?

Reply: Yes.

INTERPRETATION 01-39

Subject: Inspector Responsibilities for Form R-2 after Witnessing Pressure Test

Edition: 2001

Addendum: 2003

Question: The "R" Certificate Holder with "design only" scope certifies the design of a re-rating when no physical changes are made to the pressure-retaining item and performs and assumes responsibility for the pressure test of the rerating. Is the Inspector that witnessed the pressure test required to complete and sign the Certificate of Inspection portion of the Form R-2?

Reply: Yes.

INTERPRETATION 01-38

Subject: Design Only "R" Stamp Holders Pressure Testing and Form R-2

Edition: 2001

Addendum: 2003

Question 1: For a re-rating when no physical changes are made to the pressure-retaining item, is the pressure test, if performed, considered to be the construction portion of the alteration requiring construction certification on the Form R-2 by an "R" Certificate Holder?

Reply 1: No.

Question 2: Does the National Board Inspection Code prohibit an "R" Certificate Holder with "design only" scope from performing and assuming responsibility for the pressure test of a re-rating when no physical changes have been made to the pressure-retaining item?

Reply 2: No, provided controls for performing the pressure test are addressed in the QC manual.

INTERPRETATION 01-37

Subject: Construction Phase & Stamping when Re-rating without Physical Changes

Edition: 2001

Addendum: 2003

Question 1: Is application, by mechanical means only, of the stamping or nameplate for a re-rating when no physical changes are made to the pressure-retaining item considered to be the construction portion of the alteration?

Reply 1: No.

Question 2: Is application by welding of the nameplate for a re-rating when no physical changes are made to the pressure-retaining item considered to be the construction portion of the alteration?

Reply 2: Yes.

INTERPRETATION 01-36

Subject: Application of "R" Stamp on Non-Code Pressure Retaining Items

Edition: 2001

Addendum: 2002

Question: In order to apply the "R" stamp to a vessel that was repaired or altered, must that vessel first be constructed in accordance with the ASME code or some other recognized code or standard?

Reply: No.

INTERPRETATION 01-35

Subject: Is Pre-Assembly of a Part Considered Fabrication

Edition: 2001

Addendum: 2002

Question: During the course of a repair or alteration is the pre-assembly of a part for a pressure retaining item considered fabrication of a replacement part as addressed in RC-1050(c)?

Reply: No.

INTERPRETATION 01-34

Subject: Butter Layers Using the SMAW Process; Shielding Gas Dewpoint Temperature

Edition: 2001

Addendum: 2002

Question 1: Does RD-1060(h)(2) require that the buttering layers be deposited only using the SMAW process?

Reply 1: No.

Question 2: Is it the intent of RD-1040(i)(6) that the shielding gas dewpoint temperature be below -60°F?

Reply 2: Yes. This paragraph is worded incorrectly. A revision to correct this requirement has been prepared.

Question 3: Is it the intent of RD-1060 that the temper bead technique be used in welding a test coupon for qualification of the WPS when Alternative Welding Method 4 is to be used for repair welding?

Reply 3: Yes. The controlled bead deposition technique in RD-1060 Alternative Welding Method 4, shall be used for the qualification of the procedure in accordance with the changes in the 2004 Edition of the NBIC.

INTERPRETATION 01-33

Subject: Evaluation of Inservice Pressure Vessels and Requirement of UG-45

Edition: 2001

Addendum: 2002

Question: In evaluating a corroded nozzle on an inservice pressure vessel, do the requirements of UG-45 have to be met?

Reply: Yes, unless another industry accepted method adopted by the jurisdiction is approved.

INTERPRETATION 01-32

Subject: Are Reference Codes and Standards Acceptable

Edition: 2001

Addendum: 2002

Question: Does reference of a code or standard in the Introduction to the National Board Inspection Code (NBIC) imply it is always acceptable for use?

Reply: No. The jurisdiction retains the responsibility to decide which codes or standards to adopt for use.

INTERPRETATION 01-31

Subject: Determination of Remaining Life Applicable to Boilers and Pressure Vessels

Edition: 2001

Addendum: 2002

Question: Is it the intent of the NBIC that the procedure for determining remaining life contained in RB-3238 be applicable to both boilers and pressure vessels?

Reply: No.

INTERPRETATION 01-30

Subject: Fabrication and Installation by "R" Stamp Holder

Edition: 2001

Addendum: 2002

Question 1: When ASME is the original code of construction, does RC-1050(c) permit an owner holding an "R" Stamp to fabricate replacement parts and have the parts installed in the owner's boiler by another "R" Stamp holder?

Reply 1: No. RC-1050(c) requires these replacement parts to be fabricated by an ASME Certificate Holder.

Question 2: When ASME is the original code of construction, does RC-1050(c) permit an owner holding an "R" stamp to fabricate replacements parts and document those parts by stamping with the owner's "R" symbol, a unique serial number, and complete a Form R-3?

Reply 2: No. RC-1050(c) requires replacements parts to be documented on an ASME Manufacturer's Partial Data Report by an ASME Certificate Holder.

INTERPRETATION 01-29

Subject: Installation of Replacement Parts

Edition: 2001

Addendum: 2002

Question: When a replacement part is fabricated by welding and documentation is required by RC-1050, but does not require welding in order to install, must the repair be documented on a Form R-1?

Reply: No, the NBIC neither requires nor prohibits documenting this installation on a Form R-1.

INTERPRETATION 01-28

Subject: Use of Material That Has Been Previously Inservice

Edition: 2001

Addendum: 2002

Question: Is it prohibited to use material that has been previously in service for replacement material for a repair if that material otherwise conforms to the requirements of the original Code of Construction?

Reply: No, provided the use of the material has the concurrence of the Jurisdiction and Authorized Inspection Agency.

INTERPRETATION 01-27

Subject: Welding Using Welders Who Are Not Employed by the "R" Stamp Holder

Edition: 2001

Addendum: 2002

Question: May an "R" Certificate Holder perform welding using the services of individual welders not in his employ when it is allowed by the original Code of Construction governing the work and when the "R" Certificate Holder satisfies all of the applicable conditions established by the original Code of Construction to control the use of such welders?

Reply: Yes, provided the controls are described in the "R" Certificate Holder's Quality System manual.

INTERPRETATION 01-26

Subject: Criteria for Determining Actual Thickness and Maximum Deterioration

Edition: 2001

Addendum: 2002

Question 1: Does RB-3238(f)(1) to (f)(3) apply to all vessels and not just vessels in interrupted service?

Reply 1: No.

Question 2: The tolerance criteria in RB-3238(f)(1) is used to determine the appropriate NDE. Does this tolerance criteria apply to periodic thickness measurements?

Reply 2: No.

Question 3: Is the tolerance criteria referenced in RB-3238(f)(1) either a plus or minus value?

Reply 3: Yes.

INTERPRETATION 01-25

Subject: Documenting Alterations Performed by Two "R" Stamp Organizations

Edition: 2001

Question: An "R" Certificate organization performs the design portion of an alteration. Another "R" Certificate organization performs the necessary construction work on the alteration. Is it the intent of RC-3050 that the "R" Certificate Holder performing the design initiate the Form R-2 used to record and register the alteration?

Reply: Yes.

INTERPRETATION 01-24

Subject: NDE of Tack Welds by Welders and Welder Operators

Edition: 2001

Question 1: When not prohibited by the original Code of Construction rules for NDE personnel qualification, does the NBIC prohibit the use of welders or welding operators qualified to Section IX to visually examine tack welds made by another qualified welder within the same organization that are to be left in place and incorporated into a final weld?

Reply 1: No.

Question 2: When not prohibited by the original Code of Construction, may qualified welders or welding operators making tack welds that will be incorporated into a final weld visually examine their own tack welds?

Reply 2: Yes, when described in the Quality System.

Question 3: In lieu of identifying welders or welding operators making tack welds that become part of a final pressure retaining weld or structural attachment weld, may the "R" Certificate Holder provide a procedure in the Quality System that permits the Inspector to verify that such tack welds were made by qualified welders or welding operators?

Reply 3: Yes.

INTERPRETATION 01-23

Subject: Routine Repairs

Edition: 2001

Question: Is the repair or replacement of a fitting or valve, five (5) NPS in diameter and under considered a routine repair?

Reply: No.

INTERPRETATION 01-22

Subject: Routine Repairs

Edition: 2001

Question: When a repair conforms to the requirements of RC-2031(a)(1) and post weld heat treatment is required by the original Code of Construction, may the repair be considered routine?

Reply: Yes, subject to acceptance of the jurisdiction.

INTERPRETATION 01-21

Subject: Alternative Welding Methods in Lieu of Post Weld Heat Treatment

Edition: 2001

Question: A pressure retaining item was originally fabricated with post weld heat treatment. The post weld heat treatment was noted on its Manufacturers Data Report. Welding (such as that listed in Appendix 6, Part B) was performed on this pressure retaining item using one of the alternative welding methods (as described in RD-1000) in lieu of post weld heat treatment. Is this welding considered to be a repair?

Reply: Yes.

INTERPRETATION 01-20

Subject: Routine Repairs

Edition: 2001

Question: May the replacement of a partial section of piping (internal or external) that includes a welded fitting, such as a flange, forged elbow, or sockolet, be considered a routine repair in accordance with RC-2031?

Reply: No. RC-2031(a)(1) does not address fittings.

INTERPRETATION 01-19

Subject: Routine Repairs

Edition: 2001

Question: Does the phrase replacement of tubes or pipes, or sections thereof (5) NPS in diameter and under include the removal and replacement of a section of tube or pipe with like material?

Reply: Yes, provided the replacement material conforms to the requirements of the original Code of Construction.

INTERPRETATION 01-18

Subject: Repairs

Edition: 2001

Question: In Appendix 8-5000(b), does the phrase specification most applicable to the work include standards or specifications other than those originally used to construct the vessel?

Reply: No.

INTERPRETATION 01-17

Subject: Calculations

Edition: 2001

Question 1: Do published standard values for the pressure rating of pipe along with the design pressure satisfy the calculation requirements of RC-3021?

Reply 1: No.

Question 2: Do published standard values for the pressure temperature ratings of fittings along with the design pressure satisfy the calculation requirements of RC-3021?

Reply 2: Yes, when permitted by the original code of construction.

INTERPRETATION 01-16

Subject: Alterations to ASME Section VIII, Div. 2 Vessels

Edition: 2001

Question 1: Does the absence of reference to pressure vessels built in accordance with ASME Section VIII, Div. 2 in RC-3000 prohibit them from being altered by a company with an appropriate Certificate of Authorization to use the "R" stamp?

Reply 1: No.

Question 2: For alterations to ASME Section VIII, Div. 2 vessels, is the approving Inspector required to be employed by the "R" stamp holder's inspection agency?

Reply 2: No, the Inspector may be employed by any of the organizations listed in RC-1070.

INTERPRETATION 01-15

Subject: Pressure Test Repairs and Alterations by Isolating the Repaired Portion of a Pressure Retaining Item

Edition: 2001

Question 1: When performing a pressure test of a repair, is it permissible to isolate and pressure test the repaired area of a pressure retaining item such that the remaining parts of the pressure retaining item are not subjected to the pressure test?

Reply 1: Yes.

Question 2: When performing a pressure test of an alteration where there has not been an increase in temperature or maximum allowable working pressure, is it permissible to isolate and pressure test the altered area of a pressure retaining item such that the remaining parts of the pressure-retaining item are not subjected to the pressure test?

Reply 2: Yes.

INTERPRETATION 01-14

Subject: Repair Plan (Sec. VIII, Div. 2) AIA Acceptance

Edition: 2001

Question: Is it the intent of paragraph RC-2082(b) to prohibit the Owner-User Inspection Organization from performing the required acceptance inspection and signing of the Form R-1?

Reply: No, when all requirements of RA-3050 are met.

INTERPRETATION 01-13

Subject: Replacement of Stamped Data

Edition: 2001

Question 1: May the traceability of a pressure vessel be determined by its comparison to inspection records, drawings and the original data report matching its physical dimensions without the presence of permanent markings on the vessel when replacing a missing nameplate?

Reply 1: Yes, when such information is sufficient to conclusively establish identification of the item, such as for a one-of-a-kind item or item unique to a plant or system.

Question 2: When a jurisdictional authority does not exist, is permission to replace stamped data required by any other authority other than an Inspector from the original Authorized Inspection Agency that certified the item?

Reply 2: No.

Question 3: When the original manufacturer of a pressure vessel replaces a missing nameplate, must the manufacturer and or owner/user prove that the vessel still meets the design criteria on the replacement nameplate?

Reply 3: No.

INTERPRETATION 01-12

Subject:Use of Owner/User Personnel during Repairs of Pressure Relief Valves

Edition: 2001

Question 1: Are owner/user personnel considered to be assisting and working under the direct supervision and control of the "VR" Certificate Holder technician(s) in accordance with RA-2274(c) if the Certificate Holder's personnel leave the repair site during any stage of the repair?

Reply 1: No.

Question 2: Is the "VR" Certificate Holder responsible in accordance with para. RA-2256(h) for ensuring that only those owner/user parts accepted by the "VR" Certificate Holder are installed into the repaired valve?

Reply 2: Yes.

Question 3: Are the owner/user personnel performing repair activities required to signoff at each operation on the document required by para. RA-2256(i)?

Reply 3: No, sign-offs shall be in accordance with the "VR" Certificate Holder's quality control system.

Question 4: Under RA-2274, may a "VR" Certificate Holder establish a permanent shop facility at an owner/user's premises, using the field repair scope of their "VR" certificate of authorization?

Reply 4: No, see para. RA-2234.

INTERPRETATION 01-11

Subject: Re-rating Based on Joint Efficiency

Edition: 2001

Question: Is it the intent of the NBIC to prohibit the rerating of a pressure retaining item to a higher MAWP by performing radiography in accordance with all the relevant requirements of the edition/addenda of the code of construction and recalculating the MAWP to verify that the item can be satisfactorily operated at the new service conditions?

Reply: Yes. These requirements have been clarified in the 2002 Addendum.

INTERPRETATION 01-10

Subject: Alternative Postweld Heat Treatment Methods

Edition: 1998

Addendum: 2000

Question: Are the methods described in Part RD-1000 applicable when Postweld Heat Treatment is a mandatory requirement by the original Code of Construction due to service requirements [for example, lethal service as described by ASME Section VIII, Division I UW-2(a)]?

Reply: Yes.

INTERPRETATION 01-09

Subject: Routine Repairs

Edition: 1998

Addendum: 2000

Question: Is the seal welding of tubes which are five NPS in diameter and less considered a routine repair?

Reply: Yes.

INTERPRETATION 01-08

Subject: Manually Operated Locking Devices

Edition: 1998

Addendum: 2000

Question: In accordance with RB-3853, is a locking device operated by a manually controlled electric hydraulic pump, which exercises a hydraulic ram, which in turn holds the locking device in position, considered a manually operated mechanism?

Reply: Yes. If the action taken to engage and disengage a locking device of a quick acting closure requires manual operation, then it is a manual device. The need for operator action to start the motor is considered manual operation.

INTERPRETATION 01-07

Subject: Owner-User Inspection Organizations

Edition: 1998

Addendum: 2000

Question: Is it a requirement that a user of pressure-retaining items (having legal responsibility for the safe operation of those pressure retaining items also having and maintaining an established inspection program meeting the requirements of the National Board rules with National Board commissioned O/U inspectors who are continuously employed by the user) also be the owner?

Reply: No. Provided the user's established inspection program is acceptable to the jurisdiction or jurisdictional authority where the user is located.

INTERPRETATION 01-06

Subject: Accreditation of Repair Organizations

Edition: 1998

Addendum: 2000

Question 1: Is it a requirement of the NBIC that an organization performing repairs to pressure relief valves be accredited in accordance with RA-2200?

Reply 1: Yes, per RA-2010(d).

Question 2: Must the VR symbol be applied to the repair tag on the valve to satisfy RA-2010(d)?

Reply 2: Yes, per RA-2262(a)(2).

INTERPRETATION 01-05

Subject: "NR" Program Audits

Edition: 1998

Addendum: 2000

Question 1: Is it required that the annual audit of the "NR" Certificate Holder, as addressed by RA-2330(n), be conducted if there has been no repair, modification, or replacement activity performed under the program during the previous year?

Reply 1: Yes.

Question 2: Is the Authorized Nuclear Inspector required to be present during the annual audit of the "NR" Certificate Holder required by RA-2330(n)?

Reply 2: No, the NBIC does not specify the make-up of the audit team.

INTERPRETATION 01-04

Subject: Calibration of Pressure Gages

Edition: 1998

Addendum: 2000

Question 1: Does the NBIC require a pressure gage to be calibrated in accordance with the "R" Certificate Holder's Quality System Manual for pressure tests conducted in accordance with RC-2050 and RC-3030?

Reply 1: Yes.

Question 2: May the operational pressure gage be used for pressure tests performed to the requirements of RC-2050 or RC-3030?

Reply 2: Yes, provided accuracy of the pressure gage can be assured in accordance with the "R" Certificate Holder's Quality System as required by RA-2151(m).

INTERPRETATION 01-03

Subject: Pressure Retaining Items

Edition: 1998

Addendum: 2000

Question 1: When heat exchangers consisting of tubes and tube sheets (e.g., feedwater heaters) are manufactured and certified in accordance with an original code of construction, are repairs to the tubes and tubesheets within the scope of the NBIC?

Reply 1: Yes.

Question 2: Is the determination of primary and secondary pressure parts, for the purposes of repairs, within the scope of the NBIC?

Reply 2: No.

INTERPRETATION 01-02

Subject: Weld Metal Build-Up

Edition: 1998

Addendum: 1999

Question: If a pressure-retaining item has multiple areas requiring a weld metal buildup, does the 100 sq. in. limit described in RC-2031(a)(3) apply to the sum of the areas to be repaired?

Reply: Yes.

INTERPRETATION 01-01

Subject: Demonstration for an "NR" Certificate of Authorization

Edition: 1998

Addendum: 1999

Question 1: Does Part RA-2300 require an implementation demonstration of an applicant's quality program for issue of an "NR" Certificate of Authorization?

Reply 1: Yes.

Question 2: If an applicant for an "NR" Certificate of Authorization holds an ASME N-type Certificate of Authorization, has demonstrated implementation of their quality program within the previous 12 months, and can verify by documentation that they are capable of implementing their quality program in compliance with Part RA-2300, is it required that further implementation verification be performed for issue of the "NR" Certificate?

Reply 2: No.

INTERPRETATION 98-44

Subject: Welder Performance Qualification Using SWPS

Edition: 1995

Addendum: 1997

Question: When not prohibited by the original code of construction, may a welder performance qualification test be conducted in accordance with the standard welding procedure selected to do the repair?

Reply: Yes.

INTERPRETATION 98-43

Subject: Alterations

Edition: 1998

Addendum: 1999

Question 1: Two pressure vessels are constructed and individually stamped with the ASME Code “U” stamp. May the connection of the two vessels by a single circumferential weld be performed in accordance with the NBIC?

Reply 1: Yes.

Question 2: Are changes in the dimensions of a pressure vessel beyond that described on the data report considered an alteration?

Reply 2: Yes, if the changes affect the pressure containing capability of the pressure vessel. See Appendix 4, Glossary of Terms and Appendix 6.C, Examples of Alterations.

INTERPRETATION 98-42

Subject: Weld Buildup of Wasted Area of Boiler Tubes

Edition: 1998

Addendum: 1999

Question: May weld buildup of wasted areas on boiler tubes addressed by RD-2030(d) be considered a routine repair in accordance with RC-2031(a)(1)?

Reply: Yes, provided all requirements of RC-2031 are met.

INTERPRETATION 98-41

Subject: Compliance with Part RA-2330(g)

Edition: 1998

Question: May a holder of an ASME Certificate of Accreditation use documentation of the ASME survey to demonstrate compliance with Part RA-2330(g) of the NBIC?

Reply: No. RA-2330(g) provides the alternative to demonstration for an ASME "N" type Certificate of Authorization.

INTERPRETATION 98-40

Subject: Replacement of Threaded Stays with Welded Stays

Edition: 1998

Question: Is the replacement of a threaded stay with a welded stay always classified as a repair?

Reply: No. In some cases, the design of threaded stays and welded stays will differ, which may change the MAWP. In such cases, the work shall be performed as an alteration.

INTERPRETATION 98-39

Subject: Inspector Responsibilities for Form R-2 after Witnessing Pressure Test

Edition: 1998

Addendum: 1999

Question: A pressure-retaining item is repaired or altered in accordance with the NBIC. The pressure-retaining item and its Manufacturer's Data Report are not registered with the National Board. Is it required that the Inspector list his/her National Board Commission Number (including endorsements) in the “Certificate of Design Change Review” and “Certificate of Inspection” blocks of the appropriate Form R-1 and R-2?

Reply: Yes. See Appendix 5, instruction 28 in the Guide for Completing National Board R Forms.

INTERPRETATION 98-38

Subject: NDE in Lieu of Pressure Test

Edition: 1998

Addendum: 1999

Question: Would the desire to save time and/or expense constitute pressure testing as not being practicable?

Reply: No. The determination of "practicable" is based on technical consideration of the nature and scope of the alteration activity.

INTERPRETATION 98-37

Subject: Material Requirements

Edition: 1998

Addendum: 1999

Question: If a repair or alteration requires the use of material in accordance with RC-1050(a), are material test reports that include actual mechanical test properties required to be furnished?

Reply: Unless otherwise specifically addressed in the NBIC, all materials, including marking and test reports, shall comply with the original code of construction.

INTERPRETATION 98-36

Subject: Original Code of Construction

Edition: 1998

Addendum: 1999

Question: In RD-2050, does the thickness required by the original code of construction refer to the material thickness originally supplied?

Reply: Yes.

INTERPRETATION 98-35

Subject: Restamping or Replacement of Nameplate

Edition: 1998

Addendum: 1999

Question 1: Do the requirements of RB-4020 apply to vessels that are removed from a plant site or manufacturer’s facility and are repaired or altered by an "R" Certificate Holder?

Reply 1: Yes.

Question 2: May an "R" Certificate Holder attach a replacement nameplate supplied by the original manufacturer, after proper identification has been established and in the presence of an Inspector, on an ASME vessel?

Reply 2: Yes, provided all requirements of RB-4000 are met.

Question 3: When a nameplate is to be placed on an ASME vessel, which jurisdiction must approve the attachment of the replacement nameplate?

Reply 3: The jurisdiction where the vessel is located.

Question 4: When the original manufacturer is no longer in business, may an "R" Certificate Holder provide a replacement nameplate describing the design conditions of the ASME vessel?

Reply 4: No. The jurisdiction should be contacted when the original manufacturer is no longer in business.

INTERPRETATION 98-34

Subject: Examination and Testing

Edition: 1995

Addendum: 1996

Question: When the design rated capacity of a boiler is increased without physical work such that the design pressure and temperature are unaffected, is it required to perform a pressure test in accordance with the NBIC?

Reply: No.

INTERPRETATION 98-33

Subject: Liquid Pressure Test of Repairs

Edition: 1998

Question: Is it a requirement of the NBIC that a liquid pressure test be applied after a repair?

Reply: No. The “R” Certificate Holder is required to verify the integrity of the repair. The combination of tests and/or examinations to be performed is subject to the acceptance of the Inspector and, where required, the jurisdiction.

INTERPRETATION 98-32

Subject: Re-rating Using Higher Joint Efficiency

Edition: 1998

Question: Is it permissible to re-rate a pressure vessel using an increased joint efficiency of 1.0 in accordance with a later edition/addenda of the original code of construction if all of the butt joints were 100% radiographed in the original construction?

Reply: No.

INTERPRETATION 98-31

Subject: Replacement of a Nozzle as Routine Repair

Edition: 1998

Question: Is the replacement of a nozzle which is NPS 5 or less considered a routine repair regardless of weld thickness?

Reply: No, RC-2031 (a)(1) does not address nozzles.

INTERPRETATION 98-30

Subject: Example of Alteration Due to Grinding or Machining

Edition: 1998

Question 1: A pressure-retaining item has its surface ground or machined to remove imperfections caused during operation. Is the resulting reduction in outside diameter, length, and thickness caused by such grinding or machining considered an alteration as described in Appendix 6, Item C4?

Reply 1: No, unless the changes affect the pressure-containing capability of the pressure-retaining item.

Question 2: A pressure-retaining item has its surface ground or machined to remove imperfections caused during operation. The grinding and machining reduces the item’s thickness, length and outside diameter. Must such grinding or machining be performed by a holder of an "R" Certificate of Authorization?

Reply 2: No.

INTERPRETATION 98-29

Subject: Tube Placement

Edition: 1998

Question 1: Is the replacement of heat exchanger tube material with a material that has a different nominal composition and an allowable stress equal to or greater than the original material considered a repair?

Reply 1: Yes, provided that the thickness of the replacement material is equal to or greater than the original material thickness, and provided the replacement material satisfies the material and design requirements of the original code of construction under which the vessel was built.

Question 2: Is the replacement of heat exchanger tube material with a material that has a different nominal composition and an allowable stress less than the original material considered an alteration?

Reply 2: Yes. See Appendix 6, C7.

Question 3: May tube replacement(s) be considered a routine repair if authorization is obtained in accordance with RC-2030?

Reply 3: Yes, provided the tube material is NPS 5 or less.

Question 4: Does the NBIC require a tube replacement, which is considered to be a repair, to be documented on an R-1 Form when no welding is performed?

Reply 4: No. The NBIC does not address the documentation of non-welded repairs.

INTERPRETATION 98-28

Subject: Replacement Parts Fabricated by an "R" Certificate Holder

Edition: 1998

Question 1: Does RC-1050(c) of the NBIC permit the holder of an "R" Certificate to fabricate by welding new and exact pressure retaining replacement parts for an ASME stamped item that the "R" stamp holder is repairing?

Reply 1: No. ASME replacement parts fabricated by welding that require shop inspection by an Authorized Inspector shall be fabricated by an organization having an appropriate ASME Certificate of Authorization.

Question 2: An ASME stamped item is determined to be corroded beyond repair and the only salvageable part is the ASME Code stamping or nameplate. Is it the intent of the NBIC to permit a holder of an "R" Certificate only to build a complete new and exact pressure retaining replacement item using the original ASME construction Code, Section, Edition and Addenda and same materials, transfer and document the transfer of the ASME stamping or nameplate on an R-1 Form to the new pressure-retaining item and stamp the repair with the "R" stamp?

Reply 2: No.

Question 3: Does the NBIC define the point at which a repair becomes new construction?

Reply 3: No.

INTERPRETATION 98-27

Subject: Pressure Test; Replacement Parts

Edition: 1995

Addendum: 1996

Question 1: Does the term replacement parts, as used in RC-2050(b), include replacement parts as defined in RC-1050(a)?

Reply 1: No. RC-1050(a) describes parts supplied as material on which no fabrication welding is performed.

Question 2: Is it the intent of the 1995 Edition with the 1996 Addendum that the term replacement parts, as used in RC-2050(b), include replacement parts as defined in RC-1050(b)?

Reply 2: No. The 1997 Addendum clarifies these requirements.

Question 3: Does the term replacement parts, as used in RC-2050(b), include replacement parts as defined in RC-1050(c) and RC-1050(d)?

Reply 3: Yes.

INTERPRETATION 98-26

Subject: Resetting of PRV Springs per ASME Section 1, PG-72.3 or Section VIII, Div. 1, UG-126(c)

Edition: 1998

Question: May the spring on a pressure relief valve be reset within the guidelines of ASME Section 1, PG-72.3 or Section VIII, Div. 1, UG-126(c), as applicable, provided the repair activities are within the scope stated on the "VR" holder’s certificate and the requirements of paragraph RA-2262(b)(1) are met?

Reply: Yes, provided the set pressure is within the manufacturer’s spring range.

INTERPRETATION 98-25

Subject: Stamping on Repair Nameplate

Edition: 1998

Question: Does RA-2262(b)(3) require the repair organization to mark out the type/model number if the type/model number was changed prior to the implementation of RA-2262(b)(3)?

Reply: Yes, and the new type or model number shall be stamped on the repair nameplate in accordance with paragraph RA-2262-(a)(7).

INTERPRETATION 98-24

Subject: "VR" Certificate Holders and Code Case 1923 & 1945

Edition: 1998

Question: May a "VR" Certificate holder perform a conversion, as defined in RA2242(c), of a pressure relief valve from one certified design type to another certified type which was certified by the manufacturer in accordance with ASME Code Cases 1923 or 1945?

Reply: Yes, provided all NBIC requirements pertaining to conversions are met and the certificate holder receives from the valve manufacturer specifications and instructions which include the additional marking requirements of the applicable code case.

INTERPRETATION 98-23

Subject: Head and Shell Thickness Limitations when Installing Nozzles

Edition: 1995

Question: Is the head or shell thickness limited to 3/8 in. in thickness when installing a new NPS 3 nozzle as stated in Appendix 6, paragraph B-7?

Reply: No. The example is correct for a vessel constructed in accordance with ASME Code, Section VIII, Division 1.

INTERPRETATION 98-22

Subject: Scope

Edition: 1998

Question 1: Does the NBIC address ASME B31 piping codes?

Reply 1: Yes. See the definition of “pressure-retaining item” in Appendix 4.

Question 2: Is a nameplate required for piping system repairs/alterations performed in accordance with the NBIC?

Reply 2: Yes.

Question 3: When multiple repairs or alterations are described on a single "R" data report form, may a single nameplate be used?

Reply 3: Yes.

INTERPRETATION 98-21

Subject: Requirements for Applicants for "R" Certificate of Authorization

Edition: 1998

Question: Is it required that an applicant for an "R" Certificate of Authorization, whoseprogram includes repair of ASME Section VIII, Division 2 pressure vessels, demonstrate the capability to comply with the applicable requirements of RC-2080 to ensure the program satisfies RA-2130 (f)?

Reply: Yes.

INTERPRETATION 98-20

Subject: Re-rating

Edition: 1998

Question 1: Is derating a vessel to a lower MAWP considered an alteration or a re-rating?

Reply 1: Neither. The NBIC does not address derating. See RC-3022, footnote 1.

Question 2: In lieu of derating a corroded vessel and affixing nameplates with the new MAWP, may the pressure relief device set pressure be reduced to less than the calculated MAWP based upon actual remaining wall thickness, if the calculations are conducted in accordance with RC-3020 and RC-3021?

Reply 2: This is outside the scope of the NBIC. The jurisdiction in which the pressure vessel is located should be contacted to determine the specific procedures to be followed.

INTERPRETATION 98-19

Subject: Inspection Interval

Edition: 1998

Question: Where there are services in which pressure-retaining items are used which restrict human access due to radiological or toxicological concerns, is it permissible to utilize degradation analysis to extend the interval, or exempt the vessel from internal or on-stream evaluation?

Reply: Yes, provided it is acceptable to the jurisdiction (see RB-1000). The NBIC provides guidance only in establishing inspection intervals or exemptions (see RB-3237 and RB-3238). The jurisdiction is the final authority on inspection intervals or exemptions.

INTERPRETATION 98-18

Subject: Routine Repairs

Edition: 1998

Question: In RC-2031 (a)(1), does the phrase “and their attachments” refer to items such as: flanges, welded couplings, welded fittings for thermometers or pressure gages, or other types of pressure-retaining items?

Reply: No.

INTERPRETATION 98-17

Subject: Testing Medium and Testing Equipment

Edition: 1998

Question: For testing in accordance with paragraph RA-2281(a), is it permissible to use the 1998 ASME Code Section I blowdown requirements for valves built to earlier Code editions?

Reply: Yes.

INTERPRETATION 98-16

Subject: Prerequisites for Accreditation

Edition: 1998

Question: May an Inspector, holding a National Board Owner-User Commission and employed by an Owner-User Inspection Organization, perform inspections at more than one of his/her employer’s facilities which are National Board accredited Owner-User Organizations?

Reply: Yes, provided this is described in each Quality System Manual and is acceptable to the jurisdiction(s) where the inspections will be performed.

INTERPRETATION 98-15

Subject: Pressure Testing Requirements Related to Re-rating Activities

Edition: 1995

Addendum: 1996

Question 1: If calculations and current thickness measurements indicate that a pressure retaining item may be altered by re-rating only (no physical work being done), may the original pressure test as recorded on the Manufacturer’s Data Report be used to satisfy RC-3022(d), if the pressure test is at least equal to the calculated test pressure required to verify the integrity of said alteration, subject to the approval of the Inspector and the requirements of the jurisdiction?

Reply 1: Yes.

Question 2: If the maximum allowable working pressure (MAWP) of a pressure-retaining item must be reduced, due to wall thinning below the minimum wall thickness required to contain the MAWP stated on the manufacturer’s data report and on the ASME stamped nameplate, but the maximum allowable temperature is increased, is it the intent of the NBIC that this be considered a re-rate?

Reply 2: Yes. Any increase in pressure or temperature is considered a re-rate in accordance with RC-3022.

Question 3: If the maximum allowable working pressure (MAWP) of a pressure-retaining item must be reduced, due to wall thinning below the minimum wall thickness required to contain the MAWP stated on the manufacturer’s data report and on the ASME stamped nameplate, but the maximum allowable temperature is increased, is it the intent of the NBIC that this is, in effect, a derate and outside the scope of the NBIC?

Reply 3: No. Any increase in pressure or temperature is considered a re-rate inaccordance with RC-3022.

INTERPRETATION 98-14

Subject: Examples of Repairs and Alterations; Replacement Parts; Re-rating; Design

Edition: 1998

Question 1: Does the example of an alteration given in Appendix 6, paragraph C.7, for replacement of a pressure retaining part with a material of different allowable stress from that used in the original design, apply to use of the same material when later editions/addenda of the original code of construction permit higher allowable stresses for that material?

Reply 1: Yes, when use of the higher allowable stress value results in a reduction in material thickness.

Question 2: Does the example of a repair given in Appendix 6, paragraph B.17, for replacement of a pressure retaining part with a material of different nominal composition and equal or greater allowable stress from that used in the original design, apply to use of the same material when later editions/addenda of the original code of construction permit higher allowable stresses for that material?

Reply 2: Yes, provided there is no reduction in material thickness.

Question 3: When a replacement part is constructed using higher allowable stress values permitted by a later edition/addenda of the original code of construction and the replacement part is thinner than the part being replaced, is it required that an "R" Certificate Holder perform calculations and inspections to verify that the connecting welds and the affected portions of the pressure-retaining items are in compliance with the original code of construction?

Reply 3: Yes.

Question 4: May a pressure-retaining item be re-rated using a later edition/addenda of the original code of construction which permits higher allowable stress values for the material than was used in the original construction?

Reply 4: Yes, in compliance with the following minimum criteria:

1. The "R" Certificate Holder verifies (by calculations and other means) that the re-rated item can be satisfactorily operated at the new service conditions (e.g., stiffness, buckling, external mechanical loadings, etc.),
2. The pressure-retaining item is not used for lethal service,
3. The pressure-retaining item is not in high-cycle operation or fatigue service (i.e., loadings other than primary membrane stress are controlling design considerations.),
4. The pressure-retaining item was constructed to the 1968 Edition or later edition/addenda of the original code of construction,
5. The pressure-retaining item is shown to comply with all relevant requirements of the edition/addenda of the code of construction which permits the higher allowable stress values (e.g., reinforcement, toughness, examination, pressure testing, etc.),
6. The pressure-retaining item has a satisfactory operating history and current inspection of the pressure-retaining item verifies that the item exhibits no unrepaired damage (e.g., cracks, corrosion, erosion, etc.),
7. The re-rating is acceptable to the Inspector and, where required, the jurisdiction,
8. All other requirements of Part RC are met, and
9. Use of this Interpretation is documented in the Remarks Section of Form R2.

Question 5: May a new minimum required wall thickness be calculated for a pressure retaining item by using a later edition/addenda of the original code of construction which permits higher allowable stress values for the material than was used in the original construction?

Reply 5: Yes, in compliance with the following minimum criteria:

1. The "R" Certificate Holder verifies (by calculations and other means) that the affected portions of the pressure-retaining item can be satisfactorily operated (e.g., stiffness, buckling, external mechanical loadings, etc.),
2. The pressure-retaining item is not used for lethal service,
3. The pressure-retaining item is not in high-cycle operation or fatigue service (i.e., loadings other than primary membrane stress are controlling design considerations.),
4. The pressure-retaining item was constructed to the 1968 Edition or later edition/addenda of the original code of construction,
5. The pressure-retaining item is shown to comply with all relevant requirements of the edition/addenda of the code of construction which permits the higher allowable stress values (e.g., reinforcement, toughness, examination, pressure testing, etc.),
6. The pressure-retaining item has a satisfactory operating history and current inspection of the pressure-retaining item verifies that the item exhibits no unrepaired damage (e.g., cracks, etc.). Areas of corrosion or erosion may be left in place provided the remaining wall thickness is greater than the new minimum thickness,
7. The design change is acceptable to the Inspector and, where required, the jurisdiction,
8. All other requirements of Part RC are met, and
9. Use of this Interpretation is documented in the Remarks Section of Form R2.

INTERPRETATION 98-13

Subject: QC Manual Requirements

Edition: 1995

Addendum: 1996

Question: Does RA-2151r require an "R" Certificate Holder to list or reference, in the Quality System Manual, the specific construction codes that may be used while performing repairs or alterations?

Reply: No; however, the Quality System Manual must include provisions foraddressing requirements imposed by specific construction codes used for repairs and alterations.

INTERPRETATION 98-12

Subject: Use of Code Case 2203 in Repairs

Edition: 1995

Addendum: 1996

Question: Under the provisions of paragraph RA-2231(b)(1), is it permissible to apply ASME Code Case 2203 and convert a pressure relief valve by removing the lifting device that is required by Section VIII, Division 1, paragraph UG-136(a)(3) and Section VIII, Division 2, paragraph I-101?

Reply: Yes, provided that the “VR” Certificate Holder verifies that:

1. All of the requirements of ASME Code Case 2203 are met, and
2. That all of the requirements of the NBIC concerning conversions, and specifically, paragraphs R-2231(b)(2) and RA-2262(b)(3) are met.

INTERPRETATION 98-11

Subject: Owner-User Program Accreditation and Inspections

Edition: 1995

Addendum: 1996

Question 1: Are inservice inspections performed under the Owner-User accreditation program valid when the inspected items are intended for lease or rent, or installed for use at other locations?

Reply 1: No.

Question 2: Are repair inspections performed by an Owner-User inspection organization valid when the item(s) repaired are intended for lease or rent, or installed for use at another organization’s location?

Reply 2: No.

Question 3: May an inspector who is employed by an accredited Owner-User inspection organization perform repair authorization and acceptance inspections for pressure-retaining items not owned or used by the Owner-User accredited inspection organization?

Reply 3: No.

INTERPRETATION 98-10

Subject: NDE Requirements for ASME Section I Tube Sheet Repairs

Edition: 1995

Question 1: Do the buttwelded joints used to replace a portion of a tube sheet in an ASME Section I firetube boiler require the same nondestructive examination as longitudinal buttwelded joints in an ASME Section I boiler?

Reply 1: Yes.

Question 2: If the Reply to question #1 above is “Yes” and the NDE requirements of the original code of construction are not possible or practicable, may alternative NDE methods be used?

Reply 2: Yes, RC-1110 permits the use of alternative NDE methods that are acceptable to the Inspector and, where required, the jurisdiction.

INTERPRETATION 98-09

Subject: Inspection Requirements

Edition: 1995

Question: Does the NBIC (NBIC) require an atmospheric deaerator vessel to be inspected in accordance with part RB-3640?

Reply: No. Part RB provides recommendations for the conduct of inspections; however, the jurisdiction may mandate the use of RB-3600.

INTERPRETATION 98-08

Subject: Repair Methods

Edition: 1995

Addendum: 1996

Question: May a “blister” in a pressure-retaining item be repaired by the drilling of a hole in the center of the blister, hammering the blister flat, and rewelding the hole?

Reply: When the NBIC does not specify or otherwise limit the repair technique to be used, it is the responsibility of the "R" Certificate Holder with the concurrence of the Inspector to choose the appropriate technique. However, the chosen technique must remove the defect.

INTERPRETATION 98-07

Subject: ASME Section XI Program Boundary Components

Edition: 1995

Addendum: 1996

Question 1: If an ASME Section III component is installed in a location outside the ASME Section XI program boundary, is it a requirement of RA-2330(d) that ASME Section XI activities (e.g., VT-2 examination) be performed as part of an "NR" repair or replacement activity?

Reply 1: Yes.

Question 2: Is it permissible for an Owner to use an ASME Section III component previously installed in a location outside of the Section XI program boundary in a location within the ASME Section XI boundary as long as all previous work performed on the item was performed in accordance with NBIC requirements?

Reply 2: Yes, provided the component is examined in accordance with the appropriate ASME Section XI requirements for its intended use.

INTERPRETATION 98-06

Subject: Alternative Methods of NDE

Edition: 1995

Addendum: 1996

Question 1: May the rules of the original code of construction be used for welding nonpressure parts to a pressure-retaining item?

Reply 1: Yes.

Question 2: Is it required that the alternative methods shown in RD-1000 be applied to repairs and alterations?

Reply 2: No. RD-1000 includes alternatives that may be used in lieu of the original code of construction. When an alternative method is used, all requirements of the alternative must be met.

INTERPRETATION 98-05

Subject: Determination of Repairs Must be Made

Edition: 1995

Addendum: 1996

Question: Do the rules of the NBIC require the repair of a pressure-retaining item when the pressure-retaining item no longer complies with the original code of construction?

Reply: No, the NBIC does not provide rules for determining when a repair must be performed. (See RB-3180 and RB-3280)

INTERPRETATION 98-04

Subject: Routine Repairs

Edition: 1995

Addendum: 1996

Question 1: Does RC-2031(a)(1) limit routine repairs to a single tube or pipe?

Reply 1: No.

Question 2: May the repair of more than one tube or pipe be classified as a routine repair?

Reply 2: Yes, subject to the acceptance of the jurisdiction and the Inspector.

INTERPRETATION 98-03

Subject: Interrupted Service

Edition: 1995

Question 1: Does paragraph RB-3238(f) of the NBIC define when a pressure vessel is inservice or out-of-service?

Reply 1: No, the NBIC does not define out-of-service or in-service. This is subject to jurisdictional requirements.

Question 2: When returning a pressure vessel to service, do the requirements of paragraph RB-3238(f) apply even if the pressure vessel was inspected to other requirements while not inservice?

Reply 2: Yes.

INTERPRETATION 98-02

Subject: Conditions of Use

Edition: 1995

Addendum: 1996

Question: Does RA-2231(b) require that the "VR" stamp be applied only to pressure relief valves which meet the following conditions:

1. the valves are stamped with an ASME “V,” “UV,” or “NV” Code Symbol or marked with an ASME “HV” Symbol and have been capacity certified on the applicable fluid by the National Board; and
2. have been dissembled, inspected and repaired such that the valve’s condition and performance are equivalent to the standards for new valves in the year they were manufactured?

Reply: Yes.

INTERPRETATION 98-01

Subject: Attachments

Edition: 1995

Addendum: 1997

Question: In RC-2031(a)(1), does the phrase “and their attachments” refer to such items as:

1. joining of pipe to pipe and tube to tube;
2. attachments such as clips, lugs, rings, devices, skirts, etc.;
3. nozzles and other connections welded to shells, drums and headers?

Reply:

1. No.
2. Yes, provided postweld heat treatment is not required by the original code of construction for the attachment weld.
3. No.

INTERPRETATION 95-57

Subject: Above Ground Vessels

Edition: 1995

Addendum: 1996

Question 1: Does the interval of the lesser of five (5) years or 1/4 life refer only to an initial external inspection?

Reply 1: No.

Question 2: Does the NBIC establish an inspection interval for periodic external examinations?

Reply 2: Yes. The external inspection interval is defined in RB-3238 (e) & (f) with remaining life calculated as per RB-3236.

INTERPRETATION 95-56

Subject: Acceptance of Code Cases 1923 & 1945

Edition: 1995

Addendum: 1996

Question: Under the provisions of paragraph RA-2231 (b)(1), is it permissible for a "VR" stampholder to repair a restricted lift valve when ASME Code Case 1923-2 or 1945-3 was used in the original construction?

Reply: Yes, provided no change is made in valve lift.

INTERPRETATION 95-55

Subject: Operational Inspection

Edition: 1995

Addendum: 1996

Question: Under the provisions of paragraph RB-3550, may a repair organization that meets the requirements of RA-2220 act as the designee of a pressure vessel user to make adjustments to a steam service pressure relief valve with air as the test media, provided that:

1. the jurisdiction has authorized such adjustments;
2. no “VR” Symbol is applied to the pressure relief valve?

Reply: Yes.

INTERPRETATION 95-54

Subject: Pressure Testing

Edition: 1995

Addendum: 1996

Question: In accordance with RC-1130, is it required that the inspector witness any pressure test of a repair or alteration?

Reply: Yes, except as provided by RC-2031 (b).

INTERPRETATION 95-53

Subject: Routine Repairs

Edition: 1995

Question 1: Is the addition of a nozzle penetrating through a head or shell considered a routine repair?

Reply 1: No.

Question 2: Is a pipe nozzle that penetrates a head or shell considered a section of pipe used in RC-2031?

Reply 2: No.

INTERPRETATION 95-52

Subject: Patches, Figure 8

Edition: 1995

Addendum: 1996

Question 1: Is there a maximum length-to-width ratio for the tube window patch configuration?

Reply 1: No, the NBIC does not specify dimensions for the patch.

Question 2: Is there a maximum dimension allowed for the tube window patch?

Reply 2: No, the NBIC does not specify dimensions for the patch.

INTERPRETATION 95-51

Subject: Weld Procedures/Qualified Welders

Edition: 1995

Addendum: 1996

Question: May an "R" Certificate Holder use weld procedures and welders qualified by a technically competent group or agency?

Reply: Yes, as permitted by RC-1092 or when allowed by the original code of construction.

INTERPRETATION 95-50

Subject: R-3, R-4, & Manufacturer's Partial Data Report

Edition: 1995

Addendum: 1996

Question: Does the term “attachment” as used in RC-2072 and RC-3052 refer to Material Test Reports?

Reply: No, the term applies to R-3, R-4 and Manufacturer’s Partial Data Reports.

INTERPRETATION 95-49

Subject: P Numbers

Edition: 1995

Question: Does the example of a repair given in Appendix 6, paragraph B-17 apply only to material changes within a single P number?

Reply: No.

INTERPRETATION 95-48

Subject: R-1 Forms

Edition: 1995

Question 1: May retubing and testing a boiler whose original code of construction is ASME Section IV be documented on an R-1 if the replacement tubes are expanded as permitted in ASME Section IV, HG-360.2?

Reply 1: Yes, provided all applicable requirements of the NBIC are met.

Question 2: May repairs to saddles, frames or supports of pressure vessels be documented on an R-1?

Reply 2: Yes, provided all applicable requirements of the NBIC are met.

INTERPRETATION 95-47

Subject: Replacement Name Plates & National Board Numbers

Edition: 1995

Question: When replacing a nameplate, may the National Board number be stamped on the replacement nameplate by the original manufacturer when the manufacturer no longer holds an ASME Certificate of Authorization?

Reply: Yes, provided the requirements of RB-4000 are met.

INTERPRETATION 95-46

Subject: Examples of Repairs

Edition: 1995

Question 1: May the example of a repair given in Appendix 6, paragraph B-7 apply to a nozzle or an opening for which the axis is not perpendicular to the wall or head of a pressure-retaining item?

Reply 1: Yes, provided calculations to determine availability of reinforcement (compensation) for such construction is not a consideration of the original code of construction.

Question 2: May the example of a repair given in Appendix 6, paragraph B-7 apply to nozzles and openings larger than NPS 3?

Reply 2: Yes, provided calculations to determine availability of reinforcement (compensation) for such construction is not a consideration of the original code of construction.

INTERPRETATION 95-45

Subject: Repairs and Alterations

Edition: 1995

Question 1: Providing there is no work performed on pressure-retaining items, is the removal of a coal grate, installation of new burners, brick wall modifications, and concrete and refractory work outside the scope of the NBIC?

Reply 1: Yes, provided the required safety or safety relief valve relieving capacity is not increased.

Question 2: In a high temperature water boiler, is an increase in the maximum design output in Btu/hr, which requires an increase in the safety relief valve relieving capacity considered an alteration in accordance with the NBIC?

Reply 2: Yes.

INTERPRETATION 95-44

Subject: Alterations

Edition: 1995

Question: For a boiler stamped in accordance with the ASME Code, Section I, is it the intent of Appendix 6, paragraph C.5 that an increase in heating surface be considered an alteration only when the resulting change requires an increase in the relieving capacity of the safety valves?

Reply: Yes.

INTERPRETATION 95-43

Subject: Repairs

Edition: 1995

Question: May the welding of a new circumferential seam in a completed, code stamped and certified ASME Code pressure vessel be classified as a repair?

Reply: Yes.

INTERPRETATION 95-42

Subject: R-1 & R-2 Forms

Edition: 1995

Question: When work classified as an alteration is performed in conjunction with work on the same pressure-retaining item classified as a repair, do both Form R-1 and Form R-2 need to be prepared?

Reply: No, as long as the repair work is identified on Form R-2 along with the alteration work.

INTERPRETATION 95-41

Subject: Indications in Excess of that Allowed by the Original Code of Construction

Edition: 1995

Question 1: When performing in-service inspection, radiographic examination uncovers indications in welds made by the original manufacturer that are in excess of that allowed by the original code of construction. Is it a requirement that these welds be repaired?

Reply 1: The decision as to whether or not to perform a repair of deficiencies discovered during in-service inspection is outside the scope of the Code. See RB-3280.

Question 2: When nondestructive examination of a repair weld reveals indications in excess of that allowed by the original code of construction, must the indication be removed or reduced to an acceptable size?

Reply 2: Yes.

INTERPRETATION 95-40

Subject: Form R-2

Edition: 1995

Question 1: Does the NBIC require that the Data Report Forms used to report repairs and alterations be identical to the forms shown in Appendix 5?

Reply 1: Yes.

Question 2: May the Data Report Forms used for repairs and alterations be computer generated?

Reply 2: Yes, provided they are identical to the forms shown in Appendix 5.

INTERPRETATION 95-39

Subject: Pressure Testing of Routine Repairs

Edition: 1995

Question: Is the performance of a pressure test in accordance with RC-2050(a) required after a routine repair?

Reply: Yes, except as permitted by RC-2050(g).

INTERPRETATION 95-38

Subject: Inservice Pressure Test

Edition: 1995

Question: Does RB-3234 allow for an in-service pressure test in excess of 1-1/2 times the MAWP adjusted for temperature?

Reply: No, where any provision of the NBIC presents a direct or implied conflict with any regulation, the jurisdictional regulation shall govern. However, in these circumstances, the activity cannot be documented as meeting the requirements of the NBIC.

INTERPRETATION 95-37

Withdrawn

INTERPRETATION 95-36

Subject: Work Performed to a Code Other than the Original Code of Construction

Edition: 1995

Question: When work is performed under the NBIC to a code other than the original code of construction, is it required that the work be classified as an alteration?

Reply: No, see RC-1020. The use of a different design basis code does not necessarily require work to be classified as an alteration; however, the concurrence of the Inspector and the jurisdiction is required for this determination.

INTERPRETATION 95-35

Subject: Welding of Tube Plugs

Edition: 1992

Addendum: 1994

Question 1: Is the welding in of a plug to seal tubes in a boiler or pressure vessel considered a repair?

Reply 1: Yes.

Question 2: Does the NBIC apply to plugging tubes by welding plugs to tubes and/or their joints to tube sheets of tubes that have leaked, tubes that have corroded to an unacceptable thin wall thickness, and tubes required to be removed from service for operating reasons in boilers and pressure vessels?

Reply 2: Yes.

INTERPRETATION 95-34

Subject: Inspector Responsibilities

Edition: 1995

Question 1: In Appendix 4, the definition of an Authorized Inspection Agency refers to the National Board Rules and Regulations. If an Inspector is assigned to a shop that only holds an "R" Certificate of Authorization and performs inspections of repairs and alterations to pressure-retaining items, is the Authorized Inspector Supervisor required to audit the performance of the Inspector as specified in 3.4.3.(d) of the National Board Rules and Regulations?

Reply 1: No.

Question 2: In Appendix 4, the definition of an Authorized Inspection Agency refers to the National Board Rules and Regulations. If an Inspector is assigned to a shop that only holds an “R” Certificate of Authorization and performs inspections of repairs and alterations to pressure-retaining items, is the Inspector required to monitor the quality program?

Reply 2: No; however, the Inspector shall assure compliance with the requirements of the NBIC. See RC-1130.

INTERPRETATION 95-33(a)

Subject: Field Repairs in Other Shops Owned by the Certificate Holder

Edition: 1992

Addendum: 1994

Question: May an “R” Certificate of Authorization holder with field repair in the scope of its “R” Certificate perform repairs and alterations in other shops owned by the Certificate Holder?

Reply: No. Each shop must have its own certificate.

INTERPRETATION 95-33

Subject: Non-Load Bearing Attachments

Edition: 1995

Question: Does the NBIC specify a quantitative value below which an attachment is considered non-load bearing?

Reply: No, “non-load bearing attachment” is a generally accepted design term referring to items that transmit an inconsequential load onto the pressure retaining boundary.

INTERPRETATION 95-32

Subject: Pressure Testing

Edition: 1995

Question: In RC-2050(a), does the expression “shall be pressure tested at 80% of the maximum allowable working pressure stamped on the pressure-retaining item or operating pressure, whichever is greater” mean not less than the greater of 80% of the maximum allowable working pressure or the operating pressure?

Reply: Yes.

INTERPRETATION 95-31

Subject: Waiving the Inprocess Involvement of the Inspector

Edition: 1995

Question: Do the provisions in RC-2031(b) for waiving the inprocess involvement of the Inspector on routine repairs include waiving the requirement for the Inspector to witness a pressure test as addressed in RC-1130?

Reply: Yes.

INTERPRETATION 95-30

Subject: API-510 Reporting and Inspector Involvement

Edition: 1995

Question 1: May repairs or alterations performed in accordance with the requirements of API-510 be documented on NBIC forms R-1 or R-2?

Reply 1: No.

Question 2: May repairs or alterations performed in accordance with the requirements of API-510 be accepted by the Inspector?

Reply 2: This is outside the scope of the NBIC.

INTERPRETATION 95-29

Subject: Non National Board Member Jurisdiction Inspectors

Edition: 1995

Question: Is it the intent of the NBIC that a jurisdiction as defined in Appendix 4 which is not a member of the National Board, employ inspectors for inspection of repairs and alterations as referenced in RC-1070(a)?

Reply: Yes, RC-1070(a) does not restrict the jurisdiction to only National Board Members.

INTERPRETATION 95-28

Subject: R-1 Forms Inspector Involvement for Routine Repairs

Edition: 1995

Question: Do the provisions in RC-2031(a) for waiving the inprocess involvement of the inspector on routine repairs include waiving the requirement for the inspector to sign the Form R-1 as addressed in RC-2071(b)?

Reply: No. The requirements of RC-2071(b) are applicable for all repairs, including routine repairs. See RC-2031(d).

INTERPRETATION 95-27

Subject: Routine Repairs; Registration of R-1 Forms; Application of the "R" Symbol Stamp; Responsibility for Performing Pressure Test

Edition: 1995

Question 1: May the repair of cracks or pinholes be considered a routine repair?

Reply 1: The scope of routine repairs are defined in RC-2031. The nature of the defect is not a criteria for determining whether the repair is routine.

Question 2: Is the registration of R-1 forms an option?

Reply 2: Yes, see RC-2072. However, the jurisdiction may require registration (RC-1150).

Question 3: May the "R" Symbol Stamp be applied to a repaired item whether or not the R1 form is registered with the National Board?

Reply 3: Yes, provided all of the requirements of the NBIC are met. See RC-2060.

Question 4: Who is responsible for determining whether or not it is practical to perform a pressure test of a repaired item?

Reply 4: The "R" Certificate Holder. See RC-2050(a).

INTERPRETATION 95-26

Subject: Valve Nameplate Contents

Edition: 1995

Question: Is it the intent of RA-2262 (NB-65, paragraph 9.2(a)) that the capacity and type model number be included on the valve repair nameplate only when this information has been changed?

Reply: Yes.

INTERPRETATION 95-25

Subject: Inspectors Requirements for Form R-1 on Routine Repairs

Edition: 1995

Question: Is it required that the inspector perform a physical inspection of routine repairs to enable completion of the Certificate of Inspection block on Form R-1?

Reply: No. When the Remarks section of Form R-1 includes the Statement “Routine Repairs” in accordance with RC-2031(d), it is understood that the inspection signed for by the inspector is a document review and that a physical inspection may not have been performed.

INTERPRETATION 95-24

Subject: Nameplate Stamping and Layout

Edition: 1995

Question 1: Are nameplates required to have the same layout as the figures shown in Appendix 2?

Reply 1: No. However, all information shown in the figures must be included on the stamping or nameplate and the National Board Certificate number must appear directly below the symbol stamp.

Question 2: Are the instructions (MAWP, ° F, etc.) shown in the figures in Appendix 2 required to be included on the stamping or nameplate?

Reply 2: Yes. However, the words “Certificate Holder” and “National Board "R" Certificate Number may be omitted.

INTERPRETATION 95-23

Subject: Documentation of Repairs to Non-Symbol Stamped Cargo Vessels

Edition: 1995

Question: May repairs to cargo containers that are designed to ASME Section VIII, Division 1 but are not stamped with the “U” Symbol be documented on the form R-1, if the repair facility maintains the National Board "R" Symbol?

Reply: Yes.

INTERPRETATION 95-22

Subject: Reclassification of Pressure Retaining Items

Edition: 1995

Question: May the rules of RC-3020 and RC-3021 be followed to reclassify a vessel originally constructed to ASME, Section III, to ASME, Section VIII?

Reply: No. The NBIC does not provide rules for reclassification of pressure retaining items.

INTERPRETATION 95-21

Subject: Repairs to PWHT Vessels Without Subsequent PWHT

Edition: 1995

Question: May an ASME Section VIII, Division 1 pressure vessel that has postweld heat treatment reported on an ASME Manufacturer’s Data Report, be repaired by welding without subsequent postweld heat treatment or postweld heat treatment alternatives?

Reply: No. This is an alteration.

INTERPRETATION 95-20

Subject: Use of Earlier Edition and Addenda

Edition: 1995

Question: May the requirements of an earlier Edition and Addenda of the NBIC be used when performing a repair or alteration?

Reply: Yes.

INTERPRETATION 95-19

Subject: Original Code of Construction/Edition/Addenda

Edition: 1995

Question: When the NBIC references “the original code of construction,” is it required to use the edition and addenda of that code as used for construction?

Reply: No. The term “original code of construction” refers to the document itself, not the edition/addenda of the document. Repairs and alterations may be performed to the edition/addenda used for the original construction or a later edition/addenda most applicable to the work.

INTERPRETATION 95-18

Subject: Scope and Applicability

Edition: 1992

Addendum: 1994

Question 1: Is it a requirement of the NBIC that the rules of Appendix C-NR be applied to any repair or modification performed on an ASME Section III N-Stamped item, even though the installed item is not located in a Class 1, 2, or 3 system within the ASME Section XI Program boundaries established by the Owner in accordance with regulatory safety system classification so as to maintain its ASME Section III Code integrity?

Reply 1: No. The rules of Appendix C-NR are not required for repairs or modifications to ASME Section III items installed outside of ASME Section XI system boundaries.

Question 2: Is it a requirement of the NBIC that any work performed on an item prior to its installation in a Class 1, 2, or 3 system within the ASME Section XI Program be performed under the rules of Appendix C-NR?

Reply 2: Yes. Upon completion of the construction Code, any repairs or modifications of an item intended for service in an ASME Section XI system must be performed under the rules of Appendix C-NR to maintain the Code integrity of the item.

Question 3: Is it permissible for the owner to reuse an ASME Section III N-Stamped item that was installed in a location not within the ASME Section XI Class 1, 2, or 3 system, provided all work performed on the item was in accordance with the rules of Appendix C-NR?

Reply 3: Yes. Under the described conditions, the Code integrity would be maintained for possible reuse of the item in an ASME Section XI Class 1, 2, or 3 system application.

Question 4: Under the requirements of Appendix C-NR, is it permissible for the owner to reuse an ASME Section III N-Stamped item that was installed in a location not within the ASME Section XI Class 1, 2, or 3 system even though work had been performed on the item outside the rules of Appendix C-NR?

Reply 4: No. An item on which repair or modification activities have been performed outside of the rules of Appendix C-NR may not be subsequently used in an application which requires compliance with the rules of Appendix C-NR.

INTERPRETATION 95-17

Subject: Documenting Repairs/Responsibility for Work Performed by Others

Edition: 1992

Addendum: 1994

Question 1: Is it the intent of the NBIC to permit documented repairs (Form R-1) regardless of whether documented or undocumented repairs have been performed in the past?

Reply 1: Yes, provided the original construction was to the ASME Code.

Question 2: When an "R" Certificate Holder performs a repair on a vessel, does the Certificate Holder assume responsibility for the work performed by others on the vessel?

Reply 2: No.

INTERPRETATION 95-16

Subject: Owner/User Supplied Weld Procedures

Edition: 1992

Addendum: 1994

Question: Is it permissible for a repair organization to carry out repairs using qualified weld procedure specifications supplied by an owner-user of the boiler, pressure vessel or piping to be repaired?

Reply: No.

INTERPRETATION 95-15

Subject: Use of Replacement Parts/Assemblies from Other Inservice Vessels

Edition: 1992

Addendum: 1994

Question: Is it permissible to use an assembly from an inservice pressure vessel as a replacement part for the repair/alteration of a second vessel?

Reply: Yes, provided the intended repair/alteration has the concurrence of the jurisdiction and the Authorized Inspection Agency.

INTERPRETATION 95-14

Subject: Repairs to PWHT Vessels without Subsequent PWHT

Edition: 1992

Addendum: 1994

Question: May a welded repair to a pressure vessel be performed without postweld heat treatment or acceptable alternative to postweld heat treatment, when the pressure vessel as reported on the data report was postweld heat treated during construction?

Reply: No.

INTERPRETATION 95-13

Subject: Maximum Period between Inspection Intervals

Edition: 1992

Addendum: 1994

Question 1: Does Chapter V mandate the type of inspection to be performed?

Reply 1: No. The type of inspection (internal, external, NDE, etc.) is established by the owner-user and the Inspector provided the inspection method provides sufficient information to determine if the vessel can be safely operated.

Question 2: In accordance with paragraph U-106, may a “complete on-stream evaluation of pressure vessels” be performed in lieu of an internal inspection?

Reply 2: Yes.

Question 3: U-106(c) states that under specific circumstances and when the corrosion rate is known to be zero a vessel need not be internally inspected. Does this mean that an internal inspection is required when the corrosion rate is not zero?

Reply 3: U-106(c) provides guidance for a specific situation. The requirements of U-106(c) are not related to the requirements of U-106(b).

INTERPRETATION 95-12

Subject: Inspection of Corrosion and Other Deterioration

Edition: 1992

Addendum: 1994

Question 1: May the provisions of U-107 Inspection for Corrosion and Other Deterioration of the 1992 Edition, 1994 Addenda of the NBIC be applied to a vessel of any size?

Reply 1: Yes, provided the owner-user’s inspection program has been approved by the jurisdiction.

Question 2: When applying U-107(b) in question 1, may any of the readings taken along the length of the properly oriented line (circumferential or longitudinal) be less than the required thickness for pressure?

Reply 2: Yes, as long as the average of the readings taken along the line is equal to or greater than the required thickness for pressure.

INTERPRETATION 95-11

Subject: Re-rating of Complete Boilers or Pressure Vessels

Edition: 1992

Addendum: 1994

Question: Do the rules of the NBIC permit the re-rating of a complete boiler or pressure vessel to a higher MAWP by removing existing weld seams, reweld seams, performing radiography and recalculating using a higher joint efficiency?

Reply: No.

INTERPRETATION 95-10

Subject: Owner User Acceptance Inspection of Repairs and Alterations

Edition: 1992

Addendum: 1994

Question 1: May an Owner-User obtain an "R" Certificate of Authorization?

Reply 1: Yes.

Question 2: May repairs performed by the Owner-User holding an "R" Certificate of Authorization be inspected by Owner-User Commissioned Inspectors?

Reply 2: Yes.

Question 3: May acceptance inspections of alterations be performed by Owner-User Commissioned Inspectors?

Reply 3: No. Acceptance inspections for alterations must be performed by an Inspector employed by an Authorized Inspection Agency (insurance company or jurisdiction).

INTERPRETATION 95-09

Subject: Welding Methods as an Alternative to Postweld Heat Treatment

Edition: 1992

Addendum: 1994

Question: Is it the intent of the 1994 Addendum to the NBIC to prohibit the use of “controlled preheat” as an alternative method of postweld heat treatment in the repair of pressure vessels?

Reply: Method 1 as shown in the 1992 Edition was inadvertently omitted from the 1994 addendum. The omission should be considered an errata.

INTERPRETATION 95-08

Subject: Guide for Completing Form R-1

Edition: 1992

Addendum: 1994

Question: For instruction 13 of the guide for completing Form R-1, is a manufacturer’s serial number acceptable for “stamped identification?”

Reply: Noting the manufacturer’s serial number is one acceptable method to address “stamped identification.”

INTERPRETATION 95-07

Subject: Renewal of "R" Certificate of Authorization

Edition: 1992

Addendum: 1994

Question: May a renewed "R" Certificate of Authorization be issued based upon a manual review of an “N” type Certificate of Authorization?

Reply: Yes.

INTERPRETATION 95-06

Subject: Access Openings

Edition: 1992

Addendum: 1993

Question: May a fillet welded patch plate be installed as a repair?

Reply: No.

INTERPRETATION 95-05

Subject: When Does the NBIC Take Effect on New Boilers or Pressure Vessels

Edition: 1992

Addendum: 1993

Question: At what point following the completion of a new power boiler, heating boiler or pressure vessel may the NBIC be used?

Reply: When all requirements of the construction code have been met.

INTERPRETATION 95-04

Subject: Inspection for Corrosion and Other Deterioration

Edition: 1992

Addendum: 1993

Question: Is U-107(b) applicable to areas that have wall loss resulting from grinding?

Reply: Yes.

INTERPRETATION 95-03

Subject: Use of Similar & Non-Similar Base Metals/Repair-Alteration

Edition: 1992

Addendum: 1993

Question 1: An inservice ASME stamped pressure vessel manufactured to the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1, has its shell diameter turned down below original tolerances. The diameter is then built back up by fusion welding using weld metal having a chemical composition and tensile strength similar to that of the base metal, only to be remachined back to its original tolerances. This is done to provide more wear resistance and also to extend the useful life of the vessel. Is this procedure considered a repair?

Reply 1: Yes.

Question 2: Is the procedure specified in Question (1) considered an alteration if the weld metal has a chemical composition and tensile strength that are not similar to that of the base metal?

Reply 2: Yes.

Question 3: In order to perform the procedures specified in Questions 1 and 2 above to ASME Code vessels and maintain their integrity, in accordance with the NBIC is it required that the organization performing the work hold an “R” Certificate?

Reply 3: Yes.

INTERPRETATION 95-02

Subject: Use of R-Form When Replacing Parts with Different Materials without Welding

Edition: 1992

Addendum: 1993

Question: When a material change has been specified by the owner for a replacement tube bundle, altered to upgrade the performance, which will be installed into an existing heat exchanger shell by mechanical means (no welding), is Form R1, Report of Welded Repair or Alteration, required by R-307.1(c) necessary in addition to the manufacturer’s partial data report supplied by the parts manufacturer?

Reply: Yes. The organization, in possession of a valid Certificate of Authorization for the use of the “R” symbol stamp, that installs the part and affixes the nameplate is responsible for completing the R-1 form.

INTERPRETATION 95-01

Subject: What Editions of the NBIC Governs

Edition: All

Question: In applying the rules of the NBIC, what edition of the NBIC governs the inspection of a pressure vessel that was built prior to the latest edition of the Code?

Reply: The laws/regulations of the jurisdiction in which the object is located specify which edition of the Code applies to the object. If there is no jurisdiction, the latest edition is applicable.

INTERPRETATION 94-2

Subject: Inspector Approval for Routine Repairs

Edition: 1992

Question: Is it a requirement of the Code that the inspector give prior approval for a repair of a routine nature?

Reply: Yes (Chapter III, R-301.1, page 33).

INTERPRETATION 94-1

Subject: Repair of Valves Covered by B31.1

Edition: 1989

Question: For repair of valves, other than safety, safety relief and relief valves, covered and required by B31.1 as part of the boiler external piping, is it a requirement of the NBIC that an organization repairing such valves have a valid “R” Certificate of Authorization?

Reply: No.

INTERPRETATION 93-6

Subject: Re-rating by Performing Radiography & Recalculating Joint Efficiency

Edition: 1992

Question: Do the rules of the NBIC permit the re-rating of a completed boiler or pressure vessel to a higher MAWP by performing radiography and recalculating the pressure using a higher joint efficiency?

Reply: No.

INTERPRETATION 93-5

Subject: Requirement for Pressure Test when Re-rating a Vessel

Edition: 1992

Question: If a pressure test required for a re-rated vessel is less than or equal to the hydrostatic test performed during construction, is a new pressure test required after the re-rating is completed?

Reply: No, provided no physical work is performed.

INTERPRETATION 93-4

Subject: Owner User Acceptance Inspection of Alterations

Edition: 1992

Question: May an Owner-User Commissioned Inspector perform acceptance inspections and sign an R-1 Form for alterations performed by the Owner-User Inspector’s employer when the employer holds a valid “R” Certificate of Authorization?

Reply: No.

INTERPRETATION 93-2

Subject: Alterations

Edition: 1992

Question 1: May a fillet welded patch plate be installed as an alteration?

Reply 1: No.

Question 2: May a reinforced opening through the shell be added to a pressure vessel as an alteration?

Reply 2: Yes, provided the reinforcing pad meets all the applicable requirements of Section VIII, Division 1 of the ASME Boiler and Pressure Vessel Code, including the provision of weep holes in the reinforcing pad.

INTERPRETATION 93-1

Subject: Requirements when More than One Inspector is Involved in a Repair

Edition: 1992

Question: Is it a requirement of the Code that the inspector who performs the acceptance inspection and certifies the R-1 Form be the same inspector who authorized the initiation of the repair or alteration?

Reply: No. However, the inspector who performs the acceptance inspection and certifies the R-1 Form must be employed by the same Authorized Inspection Agency as the inspector who authorized the repair or alteration.

INTERPRETATION 92-7

Subject: Alterations with Different Certificate Holders Performing Design Calculations and Physical Work

Edition: 1992

Question: When an alteration/re-rating is performed where one organization performs the required design calculation and a second organization performs the necessary physical work, how may alteration/re-rating be performed by the two organizations?

Reply: It is the intent of the NBIC that the certification of the alteration/re-rating performed by the two organizations may be accomplished in accordance with the following procedure:

1. The “R” Certificate Holder performing the design function shall complete an R-1 Form certifying the design change. The following statement shall be included under remarks on the R-1 form: Design Only.
2. The “R” Certificate Holder performing the field activities, including the pressure testing and stamping, shall complete a second R-1 Form certifying the field activities. The “R” Certificate Holder performing the field activities shall be responsible for collecting and distributing all data report forms.

INTERPRETATION 92-6

Subject: Out of State Organizations Performing Repairs

Edition: 1992

Question: When a jurisdiction adopts the NBIC, does the jurisdiction adopt any other jurisdiction’s authorization for an out-of-state organization to perform repairs?

Reply: No.

INTERPRETATION 92-5

Subject: Alternative Requirements of NBIC when There is No Jurisdiction

Edition: 1992

Question: In some instances, the NBIC provides alternative requirements that may be applied when accepted by the jurisdiction. How may alternative requirements be applied at an installation located in an area where there is no jurisdiction?

Reply: It is the intent of the NBIC that where there is no jurisdiction, alternative requirements may be accepted by the Authorized Inspection Agency responsible for signing the R-1 form.

INTERPRETATION 92-4

Subject: Replacement of Tubes with Equal or Greater Allowable Stress

Edition: 1992

Question: Is it the intent of Chapter III, Supplement 1 that boiler or pressure vessel tube replacement using tubes of an equal or greater allowable stress value be considered a repair when the replacement material satisfies the original ASME Code requirements and such replacement has been accepted by an ASME Code stamp holder or a registered professional engineer?

Reply: No. However, a revision to the 1989 Edition of the NBIC, published in the January 1990 BULLETIN, revised these requirements.