Document: NUREG-0800
Document ID: 3c241845-034f-4f89-b12a-f51967895c13
Document Type: srp
Title: PROCESS AND EFFLUENT RADIOLOGICAL MONITORING INSTRUMENTATION
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1307/ML13071A494.pdf
Revision Date: 2023-06
Chapter: 11
Section ID: 11.5
CFR Part: 
CFR Title: 

Content:
ring systems) that supports safety-related functions, as identified by the applicant. A. Provisions should be made to ensure representative sampling from radioactive process streams and tank contents. Recirculation pumps for liquid waste tanks (collection or sample tanks) should be capable of recirculating at a rate of not less than two-tank volumes in 8 hours. For gaseous and liquid process stream samples, provisions should be made for purging sampling lines and for reducing the plate-out of radioactive materials in sample lines. Provisions for gaseous sampling from ducts and stacks should be consistent with ANSI/HPS N13.1-2011. For airborne radiation monitoring systems that rely on moving filters, the applicant should describe their intended use (e.g., for qualitative vs. quantitative evaluations of airborne radioactivity levels), calibration methods, and response time until full activity equilibrium is achieved as a function of filter paper travel rate under the radiation detector. B. When practicable, provisions should be made to collect samples from process waste streams at central sampling stations to reduce leakage, spillage, and radiation exposures to operating personnel using the guidance of SRP Section 9.3.2 in identifying systems and sampling locations and compliance with 10 CFR 20.1406 using the guidance of RG 4.21 and SRP Section 12.3-12.4. C. Provisions should be made to purge and drain sample streams back to the system of origin or to an appropriate waste treatment system (e.g., LWMS and GWMS). Purge lines should be equipped with provisions that prevent backflows and cross- contamination of nonradioactive systems supplying purging and flushing fluids (e.g., clean water, air, inert gases). The source of nonradioactive purging or flushing fluid should be protected using appropriate measures, such as check valves, backflow preventers, interlocks, differential pressures, etc. Contaminated purged fluids should be returned to the most appropriate RWMS for