Overview of the Tritium-in-Air Monitoring System of Cernavoda NPP U1 Romania - modernization and improvement project

The Tritium-in-Air Monitoring System used in Cernavoda NPP U1 is a Scintrex Model 292 and is a multi-room monitoring station for measuring tritium activity in air, particularly tritiated water vapor, ideal for installations in: nuclear power stations, tritium extraction plants, fusion facilities, other industrial tritium applications. The Tritium-in-Air Monitoring System (Scintrex Model 292) has two major limitations: the presetted setpoint is not for the tritium level of activity, is for a global activity including noble gas contribution; the presetted setpoint should be changed for each particular room, which means a major delay in the location of D2O leak sources. Both limitations can be solved by using a Tritium Monitoring Network consisting of a number of tritium monitors stationed in individual rooms and the readings are transmitted to a central computer. The data can be logged to a database (MS Access compatible) and will offer historical trends and necessary reports. This paper presents the main equipment's of the Tritium-in-Air Monitoring system, the description of this modernization project and the results of 3H emissions monitoring program (Liquid and Gaseous Effluent Program Monitoring program at Cernavoda NPP). 1 INTRODUCTION During routine operation of a CANDU reactor, various gaseous, liquid, and solid radioactive wastes are generated. The design of its systems ensures that these are minimized, but small quantities of gaseous and liquid wastes are continuously discharged at very low concentrations.(author)