Document: NRC Regulatory Guide
Document ID: 74c49394-8dbf-46e7-b62a-b85de93b47d8
Document Type: regulatory_guide
Title: Initial Test Programs for Water-Cooled Nuclear Power Plants + HISTORY - HISTORY 11/2012 – DG-1259 , Proposed Revision 4 11/2006 – DG-1166 , Proposed Revision 3 (Rev. 4)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1229/ML12298A071.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.68
CFR Part: 
CFR Title: 

Content:
n limits defined in the TS should be observed and followed. Criticality predictions for boron concentration (PWRs) and control rod positions should be provided, and criteria and actions to be taken if actual plant conditions deviate from predicted values should be established. The reactivity addition sequence should be prescribed, and the procedure should require a cautious approach to achieving criticality to prevent passing through criticality in a period shorter than approximately 30 seconds (<1 decade per minute). A-4. Low-Power Testing Following initial criticality, licensees should conduct appropriate low power tests (normally at less than 5-percent power) to (1) confirm the design and, to the extent practical, validate the analytical models, and verify the correctness or conservatism of assumptions used in the safety analyses for the facility, and (2) confirm the operability of plant systems and design features that could not be completely tested during the preoperational test phase because of the lack of an adequate heat source for the reactor coolant and main steam systems. The following list illustrates the tests that should be conducted if not previously completed during preoperational hot functional testing (tests that are specific to one type of light water reactor are noted by BWR and PWR as appropriate): a. Verify boron and moderator temperature reactivity coefficients over the temperature and boron concentration ranges in which the reactor may initially be taken critical (PWR). b. Measure control rod and control rod bank reactivity worth to (1) ensure that they are in accordance with design predictions and (2) confirm by analysis that the rod insertion limits will be adequate to ensure a shutdown margin consistent with accident analysis assumptions throughout core life, with the greatest worth control rod stuck out of the core. c. Verify adequate overlap of source- and intermediate range neutron instrumentation. d. Verify that proper operation of