From PSAs to dependability

Dependability is all the concepts (Reliability, Availability, Maintainability, and Safety) which are used to characterize the capabilities of a product to operate, to be repaired, and to not cause damage to objects or persons. PSAs (Probabilistic Safety Assessments) are a particular means of assessing the level of safety of hazardous installations. The purpose of this communication is to show that although it is still an emerging concept within EDF projects, the introduction of methods for taking account of dependability in design can be very useful at improving the safety of plants by, for example, establishing the link between operating feedback on one hand, and maintenance and operating policy on the other. Finally, we will extend our thinking on the insertion of dependability (and PSA) into design work to consideration of human factors in these projects. All too often kept apart, the technical and human aspects of design projects do have common characteristics: participation in safety and ease of operational of power plants, need for sufficiently early insertion in order to obtain pertinent result, etc. 8 figs