Document: NUREG-0800
Document ID: f03d2c71-27a1-41fd-9362-1e62c6142e13
Document Type: srp
Title: Containment Systems and Severe Accidents (Tier 1)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070653.pdf
Revision Date: 2023-06
Chapter: 14
Section ID: 14.3.11
CFR Part: 
CFR Title: 

Content:
rameters. Tier 2 means the portion of the design-related information contained in the generic DCD that is approved but not certified by this design certification rule (hereinafter Tier 2 information). Compliance with Tier 2 is required, but generic changes to and plant-specific departures from DRAFT Rev. 0 - April 1996 14.3-10 Tier 2 are governed by the change process in the design certification rule. Tier 2 information includes: (1) Information required by 10 CFR 52.47, with the exception of technical specifications and conceptual design information; (2) Information required for and FSAR under 10 CFR 50.34; (3) Supporting information on the inspections, tests, and analyses that will be performed to demonstrate that the acceptance criteria in the ITAAC have been met; and (4) Combined license (COL) action items (COL license information), which identify certain matters that shall be addressed in the site-specific portion of the final safety analysis report by a combined license applicant who references a design certification rule. Tier 2* means the portion of the Tier 2 information, designated as such in the generic DCD, which is subject to a special change process set forth in the design certification rule. This designation expires for some Tier 2* information at fuel load. The DCDs for the evolutionary designs consisted of an introduction, Tier 2 information, which is mostly the standard safety analysis report (SSAR) for the standard design), and Tier 1 information. The significance of designating design information as either Tier 1 or Tier 2 is that different change processes and criteria apply to each tier, as described in the evolutionary design certification rules. Basically, Tier 1 information is difficult to change after the design certification rule is issued because changes require a finding by the NRC that the change is needed to assure adequate protection of the public health and safety. This results in a very high threshold for change to Tier 1 by either