Document: NUREG-0800
Document ID: e1f233ab-8592-464a-9fdc-1a20ebe416a1
Document Type: srp
Title: PRESSURE SUPPRESSION POOL AS A FISSION PRODUCT CLEANUP SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070477.pdf
Revision Date: 2023-06
Chapter: 6
Section ID: 6.5.5
CFR Part: 
CFR Title: 

Content:
es its effectiveness in removing fission products from fluids expelled from the drywell or directly from the pressure vessel through the depressurization system. If the values in Regulatory Guide 1.3, Position C.1.a, are utilized in the calculations of fission product removal, then deposition by plateout should not be considered as an additional removal mechanism. Deposition by plateout is already accounted for in the Regulatory Guide values.11 6.5.5-5 DRAFT Rev. 1 - April 1996 1. Pool Decontamination Factor The decontamination factor (DF) of the pool is defined as the ratio of the amount of a contaminant entering the pool to the amount leaving. Decontamination factors for each fission product form as functions of time can be calculated by the SPARC code (Reference. 6) . An applicant may use the SPARC code or other methods to calculate 12 the retention of fission products within the pool, provided that these methods are described in the SAR adequately to permit review. If the time-integrated DF values claimed by the applicant for removal of particulates and elemental iodine are 10 or less for a Mark II or a Mark III containment, or are 5 or less for a Mark I containment, the applicant's values may be accepted without any need to perform calculations (References. 7 and 8) . A DF value of one (no retention) should be used for noble gases and for 13 organic iodides. The applicant should provide justification for any DF values greater than those given above. If the SPARC code is used for the calculation of fission product decontamination, the review should be coordinated with the branch that is responsible for establishing the input parameters for the calculations. 2. Pool Bypass Fraction The fraction of the drywell atmosphere bypassing the suppression pool by leaking through drywell penetrations is obtained as a product of the review under SRP Section 6.2.1.1.C. If B is the bypass fraction and DF is the time-integrated pool decontamination factor, then the overall