ML16211A089

Proposed Final Amendment to 10 CFR 50.55a to Incorporate by Reference Subsection IWE and Iwl,Section XI, Division 1, of the ASME Boiler and Pressure Vessel Code

ML16211A089
Person / Time
Issue date:	02/17/1995
From:	Kress T Advisory Committee on Reactor Safeguards
To:	Taylor J NRC/EDO
References
Download: ML16211A089 (2)

Text

D950217 Mr. James M. Taylor Executive Director for Operations U. S. Nuclear Regulatory Commission Washington, DC 20555-0001

SUBJECT:

PROPOSED FINAL AMENDMENT TO 10 CFR 50.55a TO INCORPORATE BY REFERENCE SUBSECTIONS IWE AND IWL, SECTION XI, DIVISION 1, OF THE ASME BOILER AND PRESSURE VESSEL CODE During the 418th meeting of the Advisory Committee on Reactor Safeguards, February 9-10, 1995, we discussed the subject final amendment. At this meeting, we had discussions with representa-tives of the NRC staff and the Nuclear Energy Institute (NEI). We also had the benefit of the document referenced.

This proposed final amendment incorporates by reference the 1992 Edition with the 1992 Addenda of Subsection IWE (Requirements for Class MC and Metallic Liners of Class CC Components of Light-Water Cooled Power Plants) and Subsection IWL (Requirements for Class CC Concrete Components of Light-Water Cooled Power Plants),Section XI, Division 1, of the ASME Boiler and Pressure Vessel Code with specified modifications and a limitation. It also expedites the schedule for performing the containment examinations. We concur with this staff position.

A number of utilities and NEI, which have commented on a draft version of this amendment, argue that it is overly prescriptive and contrary to the trend towards performance-based regulation.

However, a suitable "metric," which could be used as the basis for a performancebased inspection for the assurance of the structural integrity of the containment, seems difficult to identify.

Riskbased inspection appears to be a more promising approach to rationalizing in-service inspection of passive structural compo-nents. The Office of Nuclear Regulatory Research is actively pursuing this approach, and we hope to see risk-based concepts being used to develop requirements for in-service inspections in the not-too-distant future.

Sincerely, T. S. Kress Chairman

Reference:

Memorandum dated December 12, 1994, from E. Beckjord, Director, Office of Nuclear Regulatory Research, to J. Larkins, Executive Director, ACRS,

Subject:

Final Amendment to 10 CFR 50.55a to Incorporate by Reference Subsection IWE and Subsection IWL,Section XI, Division 1, of the ASME Boiler and Pressure Vessel Code