Context and challenges
Following the Fukushima accident, the French Nuclear Safety Authority (ASN) issued technical specifications, one of which requires the entire nuclear fleet to be equipped with an "ultimate" emergency power source. The client, a leading player in the nuclear industry, has installed an Ultimate Diesel Generators (UDG) on each of its 56 reactors at all the nuclear power plants, except at the Fessenheim nuclear power plant. These are installed in "bunkered" buildings designed to resist ultimate risks.
These generators are designed to withstand possible attacks (earthquakes, floods, tornadoes), which are far more important than those taken into account in the design of the installations and during safety reassessments. For this reason, they are subject to a qualification process for accident conditions.
This client, and more specifically its department dedicated to the engineering of the fleet, in terms of deconstruction and the environment, has asked Assystem to support in the monitoring of qualification documents, to assist some suppliers and to take over the drafting of the Qualification Maintenance Sheets (QMS).
This work consisted in reviewing all the qualification documentation (qualification programmes, test specifications, test reports, Qualification Summary Notes (QSN), Qualification Maintenance Sheets and formalizing the remarks in draft monitoring sheets. The main materials concerned were: batteries, rectifier-chargers, electrical cabinets, MV and LV (High Voltage A/Low Voltage) panels, control-command cabinets.
At the client's request, Assystem assisted some suppliers by taking charge of drafting certain parts of the qualification documents.
The QMFs drawn up by the suppliers having been deemed unsuitable by the operator, Assystem was asked by the client to take over the drafting of all the QMFs for the UDG equipment.