Document: NUREG-0800
Document ID: c4b10c9f-d82d-4bdd-884b-b83cba562a74
Document Type: srp
Title: Appendix A
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350158.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.6.5
CFR Part: 
CFR Title: 

Content:
ent. The iodine is assumed to be composed of 91% elemental iodine, 4% organic iodides, and 5% particulate iodine. 2. The reviewer ascertains the type of containment system used based on information in SAR Sections 6.2.1land 6.2.3. The primary containment leakage rate for the LOCA dose analysis is obtained from SAR Section 6.2.6 which is reviewed by the CSB. If the leakage rate is revised as a result of CSB review, the CSB will inform AEB of the change. A check is made of the LOCA assumptions listed in Chapter 15 of the SAR to verify that the primary containment leakage rate has been assumed to remain constant over the course of the accident for a BWR and to remain constant at one half of the initial leak rate after 24 hours for a PWR. Leak rates of less than 0.1% per day have not been accepted by the staff because of integrated I containment leakage test sensitivity limitations. The leakage rate used should correspond to that given in the technical specifications. 3. Where credit for a dual containment system is claimed, the reviewer veri- fies, based on SRP Sections 6.2.3 and 6.5.3, that the system meets require- ments such as existence of separate primary and secondary containments, adequate separation of the two, and ability to test the negative pressure capability of the secondary containment. Where dilution credit for a secondary containment with recirculation is claimed, adequate mixing in the secondary containment volume should be demonstrated in addition to meeting the above requirements for a dual containment system. For dual containment systems, the bypass leakage is evaluated. This leakage, usual- ly expressed as a-fraction or percentage of the primary containment leak rate, is assumed to pass from the primary containment directly to the environ- ment, bypassing the secondary containment. The secondary containment bypass leakage rate and any positive pressure characteristics in thesecondary containment are obtained from SAR Section 6.2.3 which is reviewed