Document: NUREG-0800
Document ID: ecaaf87c-d5d4-431d-ae8f-8c1afc037312
Document Type: srp
Title: PROCESS AND EFFLUENT RADIOLOGICAL MONITORING
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070612.pdf
Revision Date: 2023-06
Chapter: 11
Section ID: 11.5
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CFR Title: 

Content:
names applicable to pressurized water reactors. B - Typical system names applicable to boiling water reactors. 11.5-19 DRAFT Rev. 4 - April 1996 NG - Noble gas radioactivity. I - Iodine radioactivity, radioactivity of other radionuclides in particulate form, and alpha emitters. H3 - Tritium. R - Gross radioactivity (beta radiation, gamma radiation, or total beta plus gamma). S&A - Sampling and analysis of radionuclides, to include gross radioactivity, identification and concentration of principal radionuclides and concentration of alpha emitters. ( ) - Provisions indicated within parentheses are required only for systems not monitored, sampled, or analyzed (as indicated) prior to release by downstream provisions. DRAFT Rev. 4 - April 1996 11.5-20 APPENDIX 11.5-A DESIGN GUIDANCE FOR RADIOLOGICAL EFFLUENT MONITORS PROVIDING SIGNALS FOR INITIATING TERMINATION OF FLOW OR OTHER MODIFICATION OF EFFLUENT STREAM PROPERTIES A. Background The primary design function of a radiological effluent monitor is the detection and measurement of radioactive materials released in gaseous or liquid effluent streams of light-water-cooled nuclear power reactors. An additional design function of some monitors is that of providing a signal to automatically terminate or otherwise modify the effluent stream. Examples are the termination of exhaust airflow by closure of containment ventilation or purge isolation valves and diversion of building ventilation exhaust streams from an untreated discharge path to an alternative treatment system, such as a standby gas treatment system for a BWR plant. Depending on plant design and onsite meteorology, such an action may be necessary to mitigate the consequences of a design basis accident (DBA). The need for such mitigation is determined by calculating offsite doses that would result from the DBA. In other plant designs, radiological effluent monitors are used to actuate systems to modify or terminate releases for other purposes, e.g., to terminate