Document: NRC Regulatory Guide
Document ID: a4944d20-ef6e-480b-a45d-14425bedd2e5
Document Type: regulatory_guide
Title: ASME Code Cases Not Approved for Use (Rev. 8)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2219/ML22196A065.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.193
CFR Part: 
CFR Title: 

Content:
proved version of Code Case N-770 for incorporation directly in 10 CFR 50.55a under 10 CFR 50.55a(g)(6)(ii)(F). 4/7/13 5/7/14 0/17E 4/18/19 N-780 Alternative Requirements for Upgrade, Substitution, or Reconfiguration of Examination Equipment When Using Appendix VIII Qualified Ultrasonic Examination Systems, Section XI, Division 1 At this time, the NRC will review the application of Code Case N-780 on a case-by-case basis. The Code Case is a new alternative to the current requirements in Section XI, Appendix VIII. The technical justification for the alternative is based largely on the expertise of NDE experts and laboratory testing. Although the laboratory testing was well conducted, it was not bounding. The NRC believes that industry experience in applying the alternative is needed to ensure generic applicability and to demonstrate reliability before the alternative can be approved in RG 1.147. 4/12/21 N-806 Evaluation of Metal Loss in Class 2 and 3 Metallic Piping Buried in a Back-Filled Trench, Section XI, Division 1 NRC staff advised ASME during consideration of Code Case N-806 that the NRC had concerns and intended to review and approve the Code Case on a case-by-case basis. Following are the NRC’s concerns: (1) The rules applicable to determining corrosion rates that lead to the definition of the evaluation period and reexamination schedules are currently under development. Accordingly, the Code Case does not define the method for determining the wall loss rates, the time period 6/22/12 DG-1408, Page 36 CODE CASE NUMBER TABLE 5 ANNULLED OR SUPERSEDED UNACCEPTABLE SECTION XI CODE CASES ANNULLMENT OR REVISION DATE for the length of the evaluation, and the reexamination period/frequency. (2) The Section XI, appendices used to calculate some of the important values are nonmandatory. Licensees intending to use Code Case N-806 must submit a plant-specific request to the NRC staff for review and approval before its implementation. N-813 Alternative Requirements for