Relationship Between Physical Protection and Fire Protection Systems in Nuclear Power Plants

Several safety and operative systems coexist in Nuclear Power Plants (NPPs) aimed at achieving different tasks and objectives, The effectiveness of those systems depends on their design and relationship. Such is the caser of the relationship between physical protection and fire protection systems. Their relation should be designed in such a way to assure at least the fulfillment of their respective objectives. In accordance with the INFCIRC/225, the objectives of a physical protection system are to: minimize the possibilities of the unauthorized removal of nuclear material, and/or minimize the possibilities of sabotage. The \"Nuclear Regulatory Authority\" (ARN) performs all the nuclear regulatory activities in Argentina. To this aim, the ARN has established a regulatory framework for all nuclear activities including physical protection. Its Standard AR 10.13.1 (\"Physical Protection of Nuclear Materials and Installations\") has the goal of establishing criteria and methods to prevent the commission of intentional events that may lead to severe radiological consequences or the unauthorized removal of nuclear materials. The objectives are mainly achieved through the application of detection, delay, and response elements. In accordance with the Safety Guide No 50-SG-D2 (Rev.1), the objectives of a Fire Protection System (FPS) are: preventing fires from the beginning; detecting and extinguishing quickly those fires which do start, thus limiting the damage; and, to prevent the spread of those fires that have not been extinguished to minimize their effect on essential plant functions. These objectives can be obtained, inter alia, through physical separation, detection and extinguishing. This paper shows the experience of the ARN on improving the relationship between the above-mentioned systems. In addition, it explains how they can be balanced in such a way that a reciprocal maximum benefit is obtained.