Document: NUREG-0800
Document ID: 9738c583-ac33-4836-b8f1-580dc98eb7f0
Document Type: srp
Title: RADIOLOGICAL CONSEQUENCES OF THE FAILURE OF SMALL LINES CARRYING
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350147.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.6.2
CFR Part: 
CFR Title: 

Content:
he primary system that are exempted from the isolation requirements of GDC 55 and that are acceptable on the basis of meeting item (2) below, 2. 10 CFR Part 100, §100.11 (Ref. 3) as it relates to the radiological consequences of a small line break carrying primary coolant outside containment. The plant site and the dose mitigating engineered safety feature (ESF) systems are acceptable with respect to the radiological consequences of a postulated failure outside the containment of a small line carrying reactor coolant if the calculated whole-body and thyroid doses at the exclusion area and the low population zone outer boundaries do not exceed a small fraction of the exposure guideline values of 10 CFR Part 100, §100.11 (Ref. 3) as stated in position C.1.b of Regulatory Guide 1.11 (Ref. 2). A "small fraction" of 10 CFR Part 100 means 10 percent of these exposure guideline values, that is, 2.5 rem and 30 rem for the whole-body and thyroid doses, respectively. A plant-specific technical specification is required for the iodine activity in the primary coolant system. The specification is acceptable with respect to the postulated failure if the calculated doses resulting from the failure are within the above exposure guidelines. III. REVIEW PROCEDURES The reviewer selects and emphasizes specific aspects of this SRP section as are appropriate for a particular plant. The areas to be given attention and emphasis are determined by the similarity of the information provided in the applicant's Safety Analysis Report (SAR) to that recently reviewed on other plants and whether items of special safety significance are involved. The review consists of the following steps: 1. Review of the applicant's description of the small line failures to determine the appropriateness and conservatism of the assumptions used in the analysis. 2. Identification of the small lines connected to the primary reactor coolant system and penetrating the containment. The isolation provisions are IS.