Document: NRC Regulatory Guide
Document ID: dff52070-b179-4367-bf66-5d1107c54315
Document Type: regulatory_guide
Title: Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Normal Atmosphere Cleanup Systems in Light-Water-Cooled Nuclear Power Plants + HISTORY – HISTORY 06/2012 – DG-1280 , Proposed Revision 3 10/2000 – DG-1103 , Proposed Revision 2 (Rev. 3)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1127/ML11273A057.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.140
CFR Part: 
CFR Title: 

Content:
ulations and NRC guidance is to avoid unmonitored and uncontrolled releases of radioactive materials on the site and in uncontrolled areas, and provide information that can be used to assess potential radiological hazards. i. The adsorber section of the normal atmosphere cleanup system may contain any adsorbent material demonstrated to remove gaseous iodine (elemental iodine and organic iodides) from air with the required efficiency or better. (1) Each original or replacement batch or lot of impregnated activated carbon media used in an adsorber section should be prepared, inspected, and tested consistent with Section FF of ASME AG-1b-2009. (2) If impregnated activated carbon media is used, the adsorber section design should provide for a minimum atmosphere residence time of 0.05 seconds per centimeter (0.125 seconds per inch) of adsorbent media bed depth at rated flow. (3) Sections FD, FE, and FH of ASME AG-1b-2009 should be used to determine residence time. (4) If sample (inservice test) canisters are used, their design should be consistent with Section FE of ASME AG-1b-2009 or Appendix I to ASME N509-2002. j. Ductwork should be designed, constructed, and tested consistent with Section SA of ASME AG-1b-2009. k. Duct and housing layout designs should minimize ledges, protrusions, and crevices that could collect dust and moisture and impede personnel work performance or create avoidable industrial safety hazards. Turning vanes or other airflow distribution devices should be installed where needed to achieve acceptably uniform flow profiles and support representative airflow measurements. l. Dampers should be designed, constructed, and tested consistent with Section DA of ASME AG-1b-2009. m. Fan/blower and motor, mounting, and ductwork connections should be designed, constructed, and tested consistent with Section BA for fans/blowers and Section SA of ASME AG-1b-2009 for ducts. n. For power cycle waste offgas systems relying on activated carbon delay tanks or beds,