title: Particulate activity accumulated on a moving filter and RCS leak detection.
abstract: Analytical equations for calculating the particulate activity accumulated on a moving filter of a containment air particulate radiation monitor due to a reactor coolant system leak in the containment, including the noble gas decay products, were presented. The particulate airborne concentration in the containment was treated by assumptions of a constant reactor coolant leak rate at a constant concentration, a given aerosolizing fraction, a constant removal coefficient to account for the loss due to diffusion, settling, diffusiophoresis, and containment air recirculation operation. The ratio of moving-to-fixed filter activity was presented for radionuclide of various half-lives and for different filter moving speeds. The monitor response at one hour after the initiation of a 1-gallon per minute leak at measured reactor coolant concentrations was compared to the standard deviation of the background count rate for an operating pressurized water reactor. The detectability of a 1-gallon per minute leak in an hour can be demonstrated if the aerosolization percentage of the radionuclide in the leaked coolant is at least a few percent.
authors: The Shaw Group, Stoughton, MA, USA. wu-hung.peng@shawgrp.com
authors: Wu-Hung
authors: WH
authors: Peng
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis / Q000302:isolation & purification*; D003198:Computer Simulation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005374:Filtration / Q000295:instrumentation* / Q000379:methods; D008962:Models, Theoretical; D009688:Nuclear Reactors / Q000295:instrumentation*; D052638:Particulate Matter / Q000032:analysis / Q000302:isolation & purification*; D011829:Radiation Dosage; D011834:Radiation Monitoring / Q000379:methods*; D011835:Radiation Protection / Q000295:instrumentation* / Q000379:methods
chemical_list: D000396:Air Pollutants, Radioactive; D052638:Particulate Matter