Document: NUREG-0800
Document ID: db9f5ff5-cad8-4af5-848b-a22889b3fb51
Document Type: srp
Title: describes the design acceptance criteria for waste gas systems (as part of the
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0707/ML070730056.pdf
Revision Date: 2023-06
Chapter: 11
Section ID: 11.3
CFR Part: 
CFR Title: 

Content:
ss failures of such fortified systems. The goal of this position paper is to minimize potential radiation exposures to the public and to provide reasonable assurance that the radiological consequences of a single failure of an active component in the waste gas system will not result in a dose in excess of a small fraction (i.e., 10 percent) of the 10 CFR Part 100 limit for whole body dose to any offsite individual for a postulated event. The dichotomy in having dose criteria for systems designed to withstand explosions and earthquakes that differ from those systems that are not designed to withstand such events has led to a problem. System malfunctions appear to be the controlling failure mode and resistance to explosions and earthquakes provides no protection against operator error and system malfunction. No specific types of system malfunction failures have been designated as being representative. However, it appears that an event, such as valve misalignment or over- pressure, could result in a release approximating that from the rupture of a tank or pipe. Therefore, it was considered that, for future safety evaluations of waste gas systems, the failures analyzed could be limited to tank or pipe ruptures, but the dose criterion in every case should not exceed 25 mSv (2.5 rem) at the exclusion area boundary, given that such systems BTP 11-5-3 Revision 3 - March 2007 are fortified to withstand the effects of a hydrogen explosion and earthquakes. However, for systems not designed to withstand explosions and earthquakes, the criterion is 1 mSv (0.1 rem) at the exclusion area boundary. This BTP provides guidelines on postulated radioactive releases from a radioactive waste gas system leak or failure associated with normal operation and anticipated operational occurrences. The criteria in Section II, below, provide adequate and acceptable design solutions for the concerns outlined above. This position paper sets forth minimum requirements and does not prohibit the