The New Area Radiation Monitoring System of the Triga Nuclear Research Reactor Facility of the University of Pavia

The area radiation monitoring system of the TRIGA nuclear research reactor facility of the University of Pavia has been renewed after 30 years of operation. The new system is based on a commercial micro-computer and an home-made software developed on Lab-View platform. The system collects the data sampled by six beta-gamma dose-rate proportional counters, a free-air ionization chamber and a weather station through a serial data bus line RS232. Collected data are displayed through a desktop PC in the reactor control room and are also accessible, for a restricted number of users, through internet using the TCP/IP protocol. The software allows the operator to access the data, to modify parameters and perform tests remotely, by means of any common web browser. For an improved safety level, data are stored both in the micro-computer and in the desktop PC, both accessible remotely. The system is provided by output relays that activate automatically the nuclear alarm detection system of the facility when pre-set levels of environmental radiation dose-rate are exceeded. A watchdog, integrated into the micro-computer, tests the whole data acquisition system regularly in order to prevent possible software or hardware failures.