After signing a contract with Areva at the end of 2003 for the construction of an EPR reactor, TVO - a Finnish electricity production utility - submitted a construction permit application in early 2004. Construction of the Olkiluoto EPR reactor has begun and the "foundation stone" was officially laid in September 2005. The Finnish and French nuclear safety authorities therefore made the perfectly natural decision to work together closely on this matter. The ASN in particular gave the Finnish nuclear safety authority (STUK) access to all documents dealing with the reviews carried out since 1993 and a Finnish expert was appointed to the Advisory Committee for nuclear reactors.

Several meetings were held in 2005 between the Finnish and French nuclear safety authorities, in order to review the progress of the respective technical investigations on the projects.

The ASN and its technical support organisation, the IRSN, also presented the EPR reactor project and authorisation decree process to the Chinese nuclear safety authority in March 2005 and the Canadian nuclear safety authority in December 2005.

• development and validation of innovative technical solutions allow the emergence of new products or operating and maintenance processes and their use in place of techniques or processes offering a lesser degree of protection;
• certain research work aims to improve knowledge of the risks, which will help define the protective measures needed or even shed light on risks hitherto poorly evaluated: this is for example the case with experiments on PWR sump clogging phenomena, or studies into human reliability helping to better quantify the role of human factors;
• finally, research is useful in developing high level skills in the field of nuclear safety and radiation protection, thus helping to ensure that there is a ready supply of specialists.

The fact of being familiar with the latest research results and knowing which questions are still to be answered, means that supervisory organisations know how far a licensee can be pressed to implement safety or radiation protection improvements. The ASN therefore remains abreast of research work in order to make its supervisory actions more pertinent. Moreover, the ability of the supervisory organisations - or the experts on which they rely - to initiate research also sometimes enables them to identify safety questions that were wrongly considered to have been resolved. For example, interpretation of the experiments conducted by the IRSN brought the risk of nuclear reactor sump clogging back into the spotlight.

It is also important for the licensees to make a significant contribution to the nuclear safety and radiation protection research effort, using the results to make their facilities even safer. The ASN thus asked EDF to send it an annual statement of the budget and workforce assigned to nuclear safety and radiation protection research, so that it could examine the corresponding trends. The ASN's findings show that EDF's budget in this field has remained at a high level, even if there has been a slight downward trend in recent years. It also observes with satisfaction that research in this area is still driven by a number of factors:

• future reactor projects: the EPR project has led to R&D work into new technical solutions, some of which could be implemented on existing reactors;
• the desire of industry to improve the performance of its facilities: for example, EDF's intention to increase nuclear fuel performance in particular generated work on cladding materials and the design codes. This work is also a means of increasing the available knowledge and in some cases advancing the safety level, for example by highlighting weaknesses in the methods previously used;
• the reactor lifetime issue. EDF's wish to continue with operation of the existing plants initiated research into materials ageing and the evolution of structures and components, particularly the performance of the concrete containments and the properties of steel under the effects of irradiation;
• taking account of experience feedback from incidents; for example the research into the risk of flooding or modelling of oil slick drift.