Owing to the energy that they could release in the event of failure, regardless of the possible risk related to the fluid (liquid, vapour or gas) that would then be released, pressurised equipment entails risks that must be controlled.

This equipment (containers, exchangers, piping, etc.) is not solely limited to the nuclear industry and is present in numerous industries such as chemical industry, oil processing, papermaking, refrigeration industry. It is therefore subject to regulation set by the minister for industry, who imposes the requirements with a view to guaranteeing its safe manufacture and operation.

Application of the regulations concerning the operation of pressurised equipment in nuclear reactors is monitored by the ASN. In particular through actions on the site, this consists in checking that the licensee, who has prime responsibility for the safety of its equipment, applies the requirements imposed upon it. It must in particular:

• collect and update the information needed for safe operation of its equipment;
• maintain, monitor and repair as required to ensure that the safety level of its equipment is as required, and conduct the periodic inspections at the specified intervals on the relevant equipment;
• remove from service equipment for which the safety level is impaired;
• install and maintain protective devices designed to ensure that the maximum temperature and pressure limits are not exceeded during operation;
• submit the relevant equipment to periodic re-qualification (inspection, testing and check on safety accessories) and to inspections following significant repairs. These operations must be carried out by duly qualified independent bodies.

Nuclear power plants are the source of a number of risks to the workers, which are not always linked to the nuclear aspect of the activity. These "conventional" risks are for example linked to the electrical installations, the equipment containing pressurised gas or steam, to the hydrogen systems (explosion risk), to the nitrogen systems (anoxia), to work at height or to handling of heavy loads.

These risks must be dealt with in the first place by the licensee, through application of the regulations in force in any industry, through analysis of the risk inherent in the equipment or the activities, and through implementation of appropriate technical, organisational and human measures.

It should be noted that the steps such as to guarantee personnel safety may in certain cases contribute to nuclear safety: this is for example the case with preventing the risk of explosion, of pressurised equipment bursts or falling loads.

Verification of application of these regulations is the job of "labour" inspectors who, in the particular case of nuclear power plants, operate within the DRIRE and for the most part are also inspectors of BNIs. The inspections in this area are carried out in accordance with the directives of the Directorate for energy demand and energy markets of the General Directorate for energy and raw materials (DGEMP).