• Installation modifications

The operator notifies the Director General for Nuclear Safety and Radiation Protection of all modifications to the installation leading to updating of the safety reports, the general operating rules or the on-site emergency plan.

A new authorisation decree, examined in exactly the same way as before, must be obtained when a BNI is to undergo modifications likely to lead to non-compliance with the above-mentioned requirements, if there is a change in the operator or a modification in the perimeter of the installation, or when, owing to a fire, explosion or any other accident occurring in a BNI, it is destroyed or is closed for a period in excess of two years.

In the case of modifications made to an existing or planned installation which has already undergone a public inquiry, and if these modifications do not appreciably alter the scale or purpose of the installation and do not increase its risks, examination of the application may omit the public inquiry.

No authorisation decree was issued for a basic nuclear installation in 2005.

• Power reactor commissioning

The first load of new fuel elements may only be delivered to the reactor's storage building after authorisation by the ministers in charge of nuclear safety. This authorisation is given after examination by the ASN:
- of the storage provisions made by the operator, as presented at least three months beforehand;
- of the conclusions of an inspection carried out shortly before the date set for delivery of the fuel elements.

Furthermore, six months prior to loading of the reactor, the operator must send the ministers in charge of nuclear safety a provisional safety analysis report, together with provisional general operating rules (RGE) and an on-site emergency plan (PUI) specifying the organisation and measures to be implemented on the site in the event of an accident. The ASN consults the Advisory Committee for nuclear reactors on these documents, and then drafts its own recommendation. Upon receipt of the latter, the ministers can authorise fuel loading and pre-commissioning tests.

For PWRs, at least four successive licences are required in the startup stages:
- a fuel loading licence, authorising fissile fuel elements to be installed in the reactor vessel, enabling fuelled testing to start (pre-critical cold tests);
- a licence for pre-critical hot testing, prior to first criticality. These tests are dependent on the satisfactory outcome of the pre-critical cold tests. They are carried out while the primary system is at nominal temperature and pressure, after heating of the primary fluid by starting up the primary pumps. They may only be initiated after issue of the primary system hydrotest report by the director of the Burgundy region DRIRE, under application of an order of 26 February 1974 (see below in chapter 4);
- a licence for first criticality and power build-up to 90% of nominal power;
- a licence for power build-up to 100% of nominal power.

After first startup, within a time limit set in the authorisation decree, the operator must request authorisation for final commissioning from the ministers in charge of nuclear safety. His request is substantiated by a final safety analysis report, final general operating rules and a revised version of the on-site emergency plan. These documents must reflect the experience acquired during the operating period since the initial startup.

• Commissioning of basic nuclear installations other than power reactors

The authorisation decrees for BNIs other than power reactors stipulate that commissioning is dependent on authorisation by the ministers in charge of nuclear safety.

This pre-commissioning authorisation is accompanied by notification of technical requirements. It is granted after examination by the ASN and its technical support organisations, particularly the competent Advisory Committee, of the documents prepared by the operator. These documents include the provisional safety analysis report, the installation's general operating rules and the on-site emergency plan.

Moreover, before final commissioning of the installation, which must take place within a time set in the authorisation decree, the operator must submit a final safety analysis report to the ministers in charge of nuclear safety. This commissioning is subject to ministerial authorisation, where necessary involving updating of technical requirements and general operating rules, according to a procedure similar to that adopted for power reactors.

No BNI commissioning licence was issued in 2005.