Propuesta de mejoramiento del sistema de seguridad del irradiador de cobalto 60 del Centro de Irradiación de la EPN con enfoque de seguridad funcional (IEC61508)

Abstract

The proposed study development the improvement the designs of interlocks systems to access at bunker and the system to control the wet shield of cobalt 60 irradiator. To achieve this goal, an approach in the functional safety established by general standard IEC 61508 and specific standard IEC 61511 was made. The first one does refer to electric /electronic /electronic programmable systems related to safety and the second is about of safety instruments systems of industry processes. Also, for the assessment aforementioned systems is used the Probabilistic Safety Assessment (level 1) proposed by International Atomic Energy Agency (IAEA), this assessment did make within context of sceneries and initial events that can be generate an overexposure of occupational exposure workers of cobalt 60 irradiator considering a source with a nominal activity of 50 000 curies. As result this study can be determinate a significant improvement in the risk reduction factor of the systems designed and a decrease the annual occurrence probability of planted sceneries, thus can establish that the propose designs are under the goals of radiological safety recommended by International Council Radiological Protection (ICRP).