Pressure vessels

BNIs comprise two types of pressure vessels: those which are specifically nuclear, in other words those which contain radioactive products, and those which are more conventional and which are not specific to nuclear facilities.

The applicable regulations are detailed in the following table:

(1) The ASN has prepared a new regulatory text which, for nuclear pressure vessels, specifies construction and inspection procedures similar to those of decree 99-1046 of 13 December 1999 concerning pressure vessels, with the addition of aspects specific to nuclear facilities. This order concerning nuclear pressure vessels, dated 12 December 2005, will apply as of 2006 to the construction of pressure vessels for use in the nuclear field.

• Quality organisation

The order of 10 August 1984 concerning the quality of the design, construction and operation of basic nuclear installations specifies the steps to be taken by a BNI operator for defining, obtaining and maintaining the necessary quality of its installations and operating conditions, in order to guarantee safety.

It thus stipulates that the operator must define quality requirements for each activity concerned, employ the appropriate skills and methods for meeting these quality requirements and finally, guarantee quality by checking appropriate compliance with these requirements.

It also specifies:
- that detected discrepancies and incidents be thoroughly corrected and that preventive action be taken;
- that suitable documents testify to results obtained;
- that the operator supervise the service companies used and check compliance with procedures adopted to guarantee quality.

Experience feedback from incidents and accidents occurring in BNIs and the findings of the inspections conducted, enable the ASN to analyse the various problems in order to assess the application of the above-mentioned order of 10 August 1984.

• Water intake and effluent discharge by BNIs

BNI water intake and effluent discharges which - under application of the decree of 4 May 1995 mentioned above in point 2.1.6 - are subject to joint licensing by the ministers for Health, Industry and the Environment, are managed by technical rules defined in an order signed by the same ministers on 26 November 1999, setting the general technical rules concerning the limits and procedures for these BNI intakes and discharges subject to licensing. This text, which abrogates and replaces a number of orders dated 10 August 1976, comprises requirements which in particular concern proactive reduction of water intake and effluent discharge, enhancement of analysis resources and reinforcement of inspections, information of the various government services and of the public. Its implementation is explained in an interministerial circular of 17 January 2002, in particular with regard to the objectives and to application of the new regulations, depending on whether one is dealing with an initial application or a modification.

• Prevention of off-site detrimental effects and hazards resulting from BNI operation

BNI operation can entail detrimental effects and hazards for the environment in the broadest sense, that is for the surrounding installations and their workers, but also for the public and the environment off the site. The policy conducted by the ASN with respect to environmental protection is described in Chapter 5. It primarily aims to prevent and minimise the risks for the installations by ensuring that the following are applied:
– the above-mentioned decree of 11 December 1963, clarified by its implementing order of 31 December 1999 setting the general technical regulations designed to prevent and mitigate off-site detrimental effects and hazards resulting from operation of basic nuclear installations;
– ICPE legislation for installations of this type within the BNI perimeter.

The above-mentioned order by the ministers for the Environment and Industry of 31 December 1999 sets the general technical regulations for preventing and mitigating off-site detrimental effects and hazards resulting from BNI operation, with the exception of water intake and discharge of effluent. It introduces principles concerning waste management, prevention of accidental pollution, fire, lightning, criticality and radiolysis applicable to all nuclear equipment, including that which is situated outside the sensitive parts of the BNIs. Application of this text ensures that environmental protection concerns are taken into account by the operators at a level comparable with that required for non-nuclear industrial installations.

A revision of this order was finalised in 2005, clarifying fire risk management and introducing general technical rules concerning cooling installations, to prevent the risk of the spread of legionella. At the same time, work carried out with the DSND and the main nuclear operators led to preparation of a fire risk management guide specifying the corresponding goals defined in the amended version of the order of 31 December 1999 (see below in point 2.2.2).