Computer applications for plant operation: an automated clearance system

Despite computerized aid operators, such as the safety parameter display system, Electricite de France has developed an interesting and original computerized clearance system. This system plays an important role in outage planning and usual maintenance management, but it is also very useful for providing operators information on the status and availability of all the elementary systems (especially safety systems) and for checking technical specifications. This system was originally designed and developed at the Tricastin power plant, using terminals available to maintenance personnel, planners, and shift operations personnel. The computer simplifies the process of requesting and authorizing clearances and provides the valve lineup and tagging instructions needed to establish the clearance. The system also automatically prepares clearance sheets, clearance tags, and tagging orders for use by operators