Document: NUREG-0800
Document ID: 96cbc2a1-0072-44c5-ae86-aadfa416183c
Document Type: srp
Title: RADIOLOGICAL CONSEQUENCES OF MAIN STEAM LINE FAILURES
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350118.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.1.5
CFR Part: 
CFR Title: 

Content:
nce are involved. At the construction permit stage, there is generally insufficient information available to make meaningful radiological consequence calculations for this 15.1.5-11 Rev. 2 - July 1981 accident. At this stage, the review is limited to a brief review of the applicant's discussion of the main steam line failure accidents to determine that there are no unusual design features that would preclude the limitation of radiological consequences by appropriate limits on coolant concentrations and primary-to-secondary system leak rate. The detailed review of radiological consequences of the main steam line failure accident is done at the operating license stage when system parameters are fully developed. The standard technical specifications for the NSSS of each of the three PWR vendors include limits on the primary and secondary coolant activities and primary-to-secondary leak rate. These limits are' used by the staff in its independent dose calculations when plant specific technical specifications are not available. If the applicant .proposes to use these standard limits and the plant is one of the standard NSSS/BOP plants for which the steam line failure accident has been evaluated generically with the standard coolant activity and leakage limits, then the reviewer need not reevaluate the offsite doses from this accident provided that the atmospheric dispersion factors (X/Q values) for the site under review are lower than the limiting X/Q used in the generic review of the standard plant steam line failure. The review of main steam line failure accidents at the operating license stage consists of the following steps: 1. Review of the applicant's descriptions of the steam line failure accident, with and without offsite power. This includes a review of the time sequence of occurrence of events. 2. Review of the applicant's description of events by the RSB, includin operator actions. Review of the sequence of events to assure that the most severe case from the