- 31 - At Golfech, each crane is marked by a panel mentioning the crane reference and the rules to be followed for the parking positions as part of the " earthquake event " approach, which constitutes a good practice. However, during the inspection of the turbine hall and the diesel hall, anomalies were observed in the positioning of the cranes when they are not in use. Trolleys not in their parking position and hooks not kept in the raised position were observed. The field visits showed that the earthquake event approach needs to be better taken into account on the sites. Temporary operating facilities during reactor outage or reactor at power Some temporary devices may, if they fall, constitute a hazard by damaging or disabling other equipment important for safety. This primarily concerns biological protection and scaffolding. Before installing them, the sites must therefore analyse the risk of falling and take preventive measures. The time for which such items are in place must also be kept to the strict minimum. The inspectors therefore asked for the risk analyses performed on the occasion of the last work carried out. Reading them showed that the risk analyses presented are not always complete; for example, no account is taken of the risk of falls for objects with a mass of less than 10 kg, items which are in place for less than a week, and a distance from equipment important for safety of more than 1 metre (concrete example in Cattenom). Certain risk analyses were not carried out; for example, in the nuclear auxiliaries building at Nogent, the inspectors found that scaffolding had been in place for three months and could constitute a hazard for a pump important for safety, even though no work was in progress. At Chinon, the inspectors found the presence of items (scaffolding parts, stepladder, etc.) in the train A pumping station for reactors 1 and 2 and on the lower levels of the reactor 3 fuel building. The inspectors did however note that on several sites, there was an " earthquake event " technical guide and that the sites implemented the approach via a complete local memo. Similarly, a number of preventive measures are taken; for example at Le Blayais, the site clamps the scaffolding when the work exceeds 7 days: this modification takes half an day and helps reduce the scaffolding hazard for the IPS equipment situated nearby. Duration of presence of hazardous items in the vicinity of equipment important for safety The inspectors found that the rules varied according to the sites with respect to the time a potentially hazardous item could remain in the vicinity of an item of equipment important for safety (1 week at Tricastin, 72 hours according to head office departments). The facility visits also showed that this time was significantly exceeded in certain cases (Tricastin, Golfech). Even if some sites demonstrated good practice of the event earthquake approach, ASN finds that the inspections demonstrated that considerable progress still needs to be made on this subject, from both the documentary viewpoint (risk analyses) and the implementation and staff training aspects. Evaluation of facility conformity As part of the reactors conformity check prior to their third ten-year in-service inspection, EDF launched a survey of all the local modifications not concerning equipment important for safety which could be considered as potential hazards to equipment important for safety and classified seismic-resistant. Several sites were unable to present this list (Blayais, Nogent). 2.2.5 General evaluation on the topic "Protection of facilities in an earthquake situation" The inspections showed that on the majority of sites, some of the RFS I.3.b instrumentation requirements are not met: insufficient number of sensors, requirements concerning the maintenance and qualification of sensors not met, incorrect positioning of sensors or no justification of this positioning, lack of calibration, incorrect settings, absent or incomplete procedure. These anomalies could delay the reactor shutdown stipulated by RFS I.3.b, or could even lead to this decision not being taken. ASN will thus require that EDF examine the possibility of installing an emergency shutdown system in the event of an earthquake.
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