Sensitivity enhancement for airborne radioactivity monitoring system to detect reactor coolant leaks

摘要

A method and apparatus for measuring radioactivity associated with nuclear reactor (18) coolant leaks (16). The method includes providing a delay tank (10) in a gas sampling line (12) upstream of a radiation particulate monitor (14), the delay tank (10) allowing radioactive noble gases from the leak (16) to decay to radioactive daughter particulates that are monitored by the radiation particulate monitor (14). The apparatus includes the delay tank (10) as well as a background delay tank (20) and a valve sequencer (26) for comparing radiation associated with the delay tank (10) to radiation associated with the background delay tank (20).