The share of safety-related incidents declared is of the same order of magnitude as in previous years: nearly 20% of the incidents are linked to equipment faults and 80% to organisational and human causes. However, since 2003, a slight rise in the share of incidents linked to organisational and human causes is worth noting. This trend in particular concerns problems with preparation of maintenance (23%) and documentation problems (12%), which reflect a lack of stringency upstream of maintenance work that is important for safety, and problems with assuring and maintaining the quality of the documents required for preparing and carrying out these activities.

Among the organisational and human causes, it is also worth noting the following main origins: 18% are linked to isolated errors by the staff concerned and 12% to shortcomings in the supervision of operation and maintenance activities.

More than 95% of radiation protection incidents are linked to organisational and human causes. The following origins in particular should be noted:

• about 31% originate from specific errors, or 10% more than in 2004;
• 22% originate from incorrect preparation of the maintenance work, reflecting incomplete knowledge of radiological conditions at the maintenance location, failure to analyse interference between work sites or shifts in the schedule, the consequences of which were poorly identified,
• more than 20% originate in behavioural problems ("intentional act") or shortcomings in radiation protection ("lack of skills by one or more participants").
Environmental incidents are of three types, concerning:
• incidents linked to non-compliance with the requirements of the release orders (55%),
• release of ozone-depleting gases or greenhouse effect gases (13%),
• leaks or spillage of chemical or radioactive products (32%).

The proportion of incidents linked to releases of ozone-depleting or greenhouse gases is significantly down on 2004. EDF has made efforts to improve the situation regarding this type of release, a fact that could explain this trend if the reduction is confirmed in 2006. 70% of incidents concerning non-compliance with the requirements of the release orders have organisational and human causes, in particular specific errors on the part of the staff. With regard to the last two types of incidents, the origin is mainly due to equipment faults.

One must also underline the declaration of two incidents linked to malicious acts on two different sites. The first took place at Cattenom in December 2004 and concerned fire protection equipment, while the second occurred in April 2005 at Gravelines and concerned electrical equipment rooms. These two incidents had no safety, radiation protection or environmental consequences.