Document: NUREG-0800
Document ID: 7f6b0af0-d79e-4704-9eac-aa03109a7731
Document Type: srp
Title: RISK-INFORMED DECISIONMAKING: TECHNICAL SPECIFICATIONS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0425/ML042520260.pdf
Revision Date: 2023-06
Chapter: 16
Section ID: 16.1
CFR Part: 
CFR Title: 

Content:
lated for the TS changes and compared against the numeric guidelines referenced in this section. In calculating the risk impact of the changed case, additional changes to be implemented as part of the change can be credited. For example, in seeking an STI change, if the test strategy is also to be changed, the effect of this should also be incorporated in the risk evaluation. However, it should be noted that this SRP, Regulatory Guide 1.177, and Regulatory Guide 1.174, are applicable only to permanent (as opposed to temporary, or "one time") changes to TS requirements. TS AOT changes are permanent changes, but because AOTs are entered infrequently and are temporary by their very nature, the following TS acceptance guidelines specific to AOT changes are provided for evaluating the risk associated with the revised AOT, in addition to those acceptance guidelines given in Regulatory Guide 1. 174. Rev. 0 - August 1998 SRP 16.1-10 1. The licensee has demonstrated that the TS AOT modification has only a small quantitative impact on plant risk. An incremental conditional core damage probability (ICCDP)2 of less than 5.OE-73 is considered small for a single TS AOT modification. An incremental conditional large early release probability (ICLERP)4 of 5.OE-8 or less is also considered small. Also, the ICCDP contribution should be distributed in time such that any increase in the associated conditional risk is small and within the normal operating background (risk fluctuations) of the plant (Tier I). 2. The licensee has demonstrated that there are appropriate restrictions on dominant risk- significant configurations associated with the modification (Tier 2). 3. The licensee has implemented a risk-informed plant configuration control program. The licensee has implemented procedures to utilize, maintain, and control such a program (Tier 3). In the context of the integrated decisionmaking, the acceptance guidelines should not be applied in an overly prescriptive manner. They are