^îil'i 
COMMISSION OF THE EUROPEAN COMMUNITIES 
t:^|lliûïî COM(93) 649 final 
Brussels, 13 December 1993 
TOWARDS A SYSTEM OF SAFETY CRITERIA 
AND REQUIREMENTS RECOGNIZED THROUGHOUT THE COMMUNITY 
AND A GENUINE SAFETY CULTURE THROUGHOUT EUROPE 
Report on the implementation of the 
Council Resolutions of 22 July 1977 
and 18 June 1992 on the 
technological problems of nuclear safety 
(presented by the Commission) 
TOWARDS A SYSTEM OF SAFETY CRITERIA 
AND REQUIREMENTS RECOGNIZED THROUGHOUT THE COMMUNITY 
AND A GENUINE SAFETY CULTURE THROUGHOUT EUROPE 
Report on the implementation of the Council Resolutions 
of 22 July 1975 and 18 June 1992 on the 
technological problems of nuclear safety 
Summary and conclusions 
In 1992 the Commission adopted a report on the implementation of the Council 
Resolution of 22 July 1975 (SEC(92)79 final) and, after examining that report, the 
Council adopted a Resolution on 18 June 1992 on the various measures taken by the 
Commission on the technological problems of nuclear safety. This Resolution updates 
and reinforces the Community's role in the light of one of the key aspects of safety, 
namely the awareness at the end of the 1980s of a small but not negligible probability of 
severe accidents which could have repercussions throughout the world. 
The Council Resolution of 22 July 1975 committed the Member States and the 
Commission to a process of gradual harmonization of Community safety practices and 
rules. The Resolution of 18 June 1992, while confirming the objectives of the earlier 
Resolution, recommends that cooperation between the Community's safety authorities be 
stepped up and that the know-how and experience gained by the European Community 
should be transferred to the countries of Central and Eastern Europe and the former 
Soviet Union. At the beginning of 1993 it can be said that the first measures towards 
achieving the latter objective are going in the right direction. As regards the measures 
undertaken since 1975 in the Community, in a climate largely adverse to the development 
of nuclear energy, harmonization of nuclear safety practices and rules in Europe is 
progressing satisfactorily. 
The fundamental objective of establishing a safety system which guarantees protection of 
the public and the environment against the risks arising out of the use of nuclear energy 
is being achieved with the aid of two Community working groups set up by the 
Commission. One of them, the Reactor Safety Working Group (RSWG), brings together 
representatives of all the organizations involved in the safety of installations: power 
station suppliers, electrical utilities, safety authorities and their technical support 
organizations; the other, the Nuclear Regulators' Working Group (NRWG) consists 
solely of the representatives of safety authorities. Representatives of the Swedish, Finnish 
and, more recently, Swiss counterpart organizations also sit on these two Committees. 
The safety system gradually being established focuses on three aspects: organization of 
safety, in particular at public authority level, the methods used to assess it and technical 
regulations. 
Considerable progress has been made on the organization of safety which is fairly 
advanced and a recent report entitled "Objectives and requirements of a nuclear 
safety regulatory regime" gives a fairly complete overview of the principles on 
which there is a European consensus. 
As regards the methods of evaluating safety, the report COM(88)788 entitled 
"Assurance of the safety of nuclear power plants - Objectives and methods" will 
also, once it has been updated to take account of the problem of severe accidents, 
be an almost complete consensus document. 
The situation is a complex one as regards technical regulations because of the 
different hierarchies of regulations, which sometimes require initiatives from 
industrial responsibles, and due to the very broad range of problems to be taken 
into account in the various phases involved with a nuclear power station, such as 
the choice of site, its design, commissioning, operation and decommissioning. 
The 1981 document entitled "Safety principles for light-water-reactor nuclear 
power plants" (COM(81)5l9 final) was an important milestone, however, by 
establishing a list of fundamental principles and general safety principles 
recognized at Community level, and it mapped out future action concerning safety 
requirements and codes and standards. The 1988 document "Assurance of the 
safety of nuclear power plants - Objectives and methods" shows that the levels of 
safety achieved in Community countries are practically equivalent, and points out 
the areas, notably severe accidents, where progress still needs to be made. 
In 1992 two events had a significant impact on the Commission's activities in the field 
of safety: one inside the Community, the prospect of the single market in 1993, 
reactivated the process of harmonizing safety requirements to be met by future 
generations of power stations; the other outside the Community, in the form of the 
gradual implementation of the PHARE and TACIS programmes of assistance to the 
countries of Central and Eastern Europe and the former Soviet Union, brought the 
attention of those responsible for safety in the Community to the problems presented by 
the East and brought about greater cohesion and large-scale collaboration with their 
counterparts in the countries of the East. 
At European level, the opening of frontiers to the free movement of nuclear equipment 
and above all the opening up of public contracts to free intra-Community competition 
along with initiatives taken by third countries and in particular the USA to develop 
innovative plants with improved safety features compared with the present ones, have 
prompted the two main European constructors and operators to pool their know-how for 
a project that can be approved in their two countries. This project will conform to the 
fundamental principles of safety indicated above, but with the additional factor of severe 
accidents taken into account from the design stage. As regards safety options and 
requirements as well as the rules and criteria to be applied, the two constructors and 
operators will take joint decisions from the earliest design stage which will then be 
gradually submitted to the safety authorities. At present this project is denoted by the 
acronym EPR (European Pressurized Reactor). It is reasonable to hope that the various 
parties responsible for nuclear safety in other European countries will also gradually come 
in on the act. The Commission will in any case try to help this evolution, the issue of 
which eventually leading the concepts of equivalence and harmonization to be replaced 
by common rules. 
Following the political upheavals in Eastern Europe and the former Soviet Union and the 
West's realization of the problems presented by the safety of nuclear power stations in 
those countries, one of the main concerns of the Council and the Commission was for the 
urgent practical assistance provided by the Community under the PHARE and TACIS 
3 
programmes to be accompanied by a real transfer of the approach to safety, methods, 
practices, rules and criteria applied by the Community to help the countries of the East 
gradually to bring the safety of their installations up to an equivalent level to that of 
European installations. The Commission, which does not wish to limit this objective 
solely to existing plants but also to future generations of plants, has recently taken 
significant steps in this direction, in the form of a joint study between, on the one hand, 
the constructors and technical support organizations of the Community's safety 
authorities, coordinated by EDF and GRS and, on the other, their Russian counterparts. 
This is a joint Community-Russian study of how to improve safety in the main reactor 
systems, the principal objective being to identify joint measures which could help to 
accelerate this improvement and have an impact on the future of nuclear energy in 
Europe. This analysis will also provide support for a vast operation of technological 
transfer to the Russian industry, safety evaluation establishments and research and 
development institutes so that European know-how can help future Russian projects. 
The contacts established at the end of 1990 between the safety authorities of the 
Community Member States, as represented in the NRWG, and their counterparts in the 
countries of Central and Eastern Europe and the former Soviet Union rapidly led in 1991 
to the Commission's establishing "CONCERT" (Concertation on European Regulatory 
Tasks) for the purposes of developing cooperation between Community and Eastern 
European safety authorities, the aim being to take advantage of the concertation structures 
established in the West in the NRWG to optimize cooperation. The three areas proposed 
for joint activities were as follows: regulatory bases and procedures, regulatory aspects 
of technical and operational problems and on-going assistance programmes. It soon 
became clear that the transfer to these Eastern European countries of experience gained 
by the Community in terms of organization, procedures and regulations had to be one of 
the essential aspects of assistance to Eastern countries on nuclear safety. At the 
prompting of the NRWG the Commission set up, at the beginning of 1992, the 
"Regulatory Assistance Management Group" (RAM(i) in support of the CONCERT 
structure and consisting of the safety authorities belonging to the NRWG willing to lend 
their support to their counterparts in Eastern Europe as part of technical assistance 
programmes financed by the Community. The RAMG supervises assistance activities and 
advises the Commission on proposals made in this area. More particularly, its job is to 
define, organize and implement support for the regulatory authorities in the countries of 
Central and Eastern Europe and the former Soviet Union, to help the Commission 
establish a regional assistance programme for those countries, to advise it on requests 
emanating from the beneficiary countries so as to maximize the benefits and to examine 
and evaluate the results of the assistance programmes. 
To solve the problems concerning assistance to the countries of Central and Eastern 
Europe and the former Soviet Union, viz. operational safety, design safety, support for 
safety authorities, to meet a huge demand and to guarantee the beneficiary countries 
consistent aid across the board in terms of safety, the Commission has encouraged the 
bringing together of the European organizations called upon to provide assistance: 
electrical utilities (TPEG), safety authorities (RAMG) and their support organizations 
(TSO), and the constructors of power stations (ENAC). The collaboration between these 
consortia is extremely fruitful and the projects run provide European organizations with 
a unique opportunity for practical harmonization on a joint basis. While all the activities 
run by the Commission were designed to harmonize safety practices and rules at European 
level by way of a more or less abstract process of discussion and comparison of national 
positions the implementation of assistance projects gives European organizations the 
opportunity to apply the results of Community cooperation to the beneficiaries of 
assistance. Concertation and cooperation, which is established pragmatically between the 
partners jointly responsible for one and the same project can only, in the long-term, be 
to the benefit of Community action, whose success is indirectly furthered by the assistance 
programmes. 
This favourable context for the Commission's intended policy, with projects carried out 
jointly in the frame of EPR as well as in assistance programmes, will have a certain 
knock-on effect at Community level which will gradually bring the safety authorities of 
the Member States, the TSOs, electrical utilities and power plant suppliers to discuss and 
come to an agreement on the specific safety problems presented in the Member States, 
be they problems of the design safety of installations, operational safety or approval. 
This trend will strengthen cohesion and solidarity between those parties responsible for 
safety within the Community and make for better acceptance of nuclear energy by the 
public at large. 
Thus, a complex process of consultation, discussion and concertation which has been 
conducted for more than twenty years will gradually lead to a safety system which is 
recognized on a broader international scale than the Community and in particular in the 
countries of Central and Eastern Europe and the former Soviet Union. Absolute safety, 
however, is as Utopian an objective as absolute health. Safety can always be improved 
and at a time when technological progress is practically non-stop this has to be a constant 
objective of the authorities who must ensure that sufficient resources are available and put 
to proper use. Community concertation on existing installations must take account of the 
results of research as long as there are objective reasons for engaging in it. As regards 
the future generations of power plants, technological innovation will always have to be 
examined in terms of safety and for the benefit of safety. 
Over and above the system of safety being developed the final objective will be to 
establish a genuine safety culture at Community level and to project it throughout Europe. 
TOWARDS A SYSTEM OF SAFETY CRITERIA 
AND REQUIREMENTS RECOGNIZED THROUGHOUT THE COMMUNITY 
AND A GENUINE SAFETY CULTURE THROUGHOUT EUROPE 
Report on the implementation of the 
Council Resolutions of 22 July 1975 
and 18 June 1992 on the 
technological problems of nuclear safety 
h 
Technological problems of nuclear safety 
In 1992 the Commission adopted a Report on the implementation of the Council 
Resolution of 22 July 1975 (SEC(92) 79 final), and the Council, after examining that 
Report, adopted a resolution on 18 June 1992 on the various activities carried out by the 
Commission on the technological problems of nuclear safety. The Commission Report 
referred to the period 1987-91 while the reference period for the Council Resolution was 
1991, which is why it was worth looking to see whether the various objectives of the 
Council Resolution tied in with the current situation at the beginning of 1993. Before 
going into the individual points of the resolution, it is worth taking a brief look at how 
the nuclear energy situation has changed in the world both economically and politically 
since 1991, at the principal events inside and outside of the Community which have 
affected the activities of the Commission and at the results obtained on the technological 
problems of nuclear safety. 
1991 saw a cutback in nuclear plant construction programmes in countries regarded as 
being in favour of nuclear energy (France, Japan, USA), a de facto or de jure moratorium 
in a lot of countries (Spain, Italy, the Netherlands, Sweden, United Kingdom, Germany, 
Belgium, etc.) and poor export prospects for European companies. This situation was 
relieved to some extent by the abundance of fossil fuels available at relatively stable low 
prices (oil from the Middle East, gas and coal from the countries of Eastern Europe and 
the former Soviet Union) and by the obsession with the worrying state as regards the 
safety of nuclear power stations in operation in Eastern European countries and the 
former Soviet Union, which had a negative influence on public opinion in western 
countries. In 1992 the preliminary studies on the EFR (European Fast Reactors) project 
were practically completed and no decision was taken to restart the Creys-Malville fast 
breeder reactor. 
With public opinion beginning to realise the negative effects on the environment caused 
by fossil fuels, investments in the nuclear field could pick up in the medium term. That 
said, how studies on the impact on the environment of fossil fuels are interpreted is 
sometimes contradictory and public opinion in Europe has not yet taken on board the 
enormous rise in the demand for energy in Asia. 
At the beginning of 1993 the general situation is still fairly gloomy. 
The situation as regards the safety of installations is completely different. The political 
will to keep improving the safety of existing installations has not let up and in Western 
countries the parties responsible for running nuclear programmes (safety regulators, plant 
suppliers, utilities and research organisations) feel that safety is absolutely essential and 
comes before any economic considerations. 
In 1992 two events had a significant impact on the activities of the Commission in the 
field of safety: one inside the Community, this being the opening of the single market 
in 1993, which restarted the process of harmonizing the safety requirements to be met by 
future generations of power stations; and the other outside the Community, in the form 
of the gradual implementation of the PHARE and TACIS programmes of assistance to the 
countries of Central and Eastern Europe and the former Soviet Union, which brought the 
attention of the various parties responsible for safety in the Community to the problems 
presented in the East and had the effect of stepping up cohesion and collaboration witli 
their Eastern counterparts. It is in this general context that the individual terms of the 
Council Resolution of 18 June 1992 should be viewed to see how the Commission has 
taken them into account in implementing its policy. The significance of Commission 
action , the means employed to encourage systematic concertation between national 
bodies, the requisite scientific and technical bases, and the extension and projection of 
measures taken beyond the boundaries of the Community to encompass the countries of 
Central and Eastern Europe and the former Soviet Union will thus be looked at one after 
the other. 
I.Significance of Commission action 
The Council "recognises the progress towards an equivalent and satisfactory degree of 
protection of the population and of the environment in the Community at the highest 
practical safety levels, as stipulated by the Resolution of 1975, and in contributing to the 
international acceptance of similar high safety levels". 
The Commission action concerning the technical and regulatory aspects of reactor safety 
generally forms part of the "harmonization of safety rules and criteria". The term 
harmonization is not always the best to describe Community action. Sometimes it could 
be replaced by the idea of search for equivalence, but at this stage a difference should be 
made between installations being built or in operation and future generations of power 
stations. As regards the former, the method used from the outset to implement the 1975 
Council Resolution has been to promote systematic concertation between the various 
parties responsible for safety in the Member States, safety and regulatory authorities, 
electrical utilities operating the installations and suppliers within Commission working 
groups in order to reach a consensus on the equivalence of approaches, methodologies, 
options and safety rules and criteria applied in the Member States. This policy is 
adopted, as will be seen below, in very many areas. A list of the fundamental principles 
of safety, as accepted and applied de facto throughout the Community, was established 
in 1981, this being less the result of harmonization between the respective positions of 
the Member States than the adoption of a common position to be checked a posteriori 
against existing installations. In 1989 the Commission Communication to the Council 
"Assurance of the safety of nuclear power plants - objectives and methods" (COM(88) 
788) described the safety objectives and methods on which general consensus had been 
established within the Community. 
As regards the future generations of nuclear power plants, the prospects of Community 
action are rather different. At European level the opening of frontiers to the free 
movement of nuclear material and above all the opening of public contracts to open intra-
Community competition along with initiatives taken in third countries and in particular 
in the USA to develop innovative plants with improved safety features compared with the 
present ones have prompted the two main plant suppliers and electrical utilities in Europe 
to pool their know-how into a project that can be approved in both their countries. This 
type of project ties in with the basic safety principles mentioned above, with the severe 
accidents scenario added as from the design stage, and the safety options, requirements, 
rules and criteria to be applied take the form, from the earliest stage of the project, of 
joint decisions by the two constructors and generators; these are then gradually submitted 
to the safety authorities. This project currently has the acronym EPR (European 
Pressurized Reactor). It is to be hoped that the various parties involved in nuclear safely 
in the other European countries will also gradually join in this process. The Commission, 
for its part, will make every effort to facilitate this trend, which should see the concepts 
of equivalence and harmonization replaced by common rules. 
If the basic principles which apply to all types of reactor are the top of the nuclear rules 
hierarchy, followed by the safety options and requirements, rules and criteria, which 
depend greatly on the design of the plant, at the bottom of the list come the 
manufacturing and control codes and standards of components of nuclear plants, which 
are used by the suppliers in particular to guarantee the integrity of steel components for 
the life of the installations. The Commission's work in the field of codes and standards, 
which was initially geared to fast breeder reactors, has gradually shifted towards light 
water reactors. This is pre-normative work intended to establish the technical bases of 
a harmonized approach prior to the development of European industrial codes. 
Implementation of the EPR project gives a new dimension to this work. The codes and 
standards usai to design and control the components of future EPR-type plants will 
obviously have to have a European label. It is hard to imagine the Commission setting 
about developing a complete set of codes and standards since this would be too much of 
a task and in some ways superfluous, given the time and effort already invested, for 
example, in France with the RCCM code, in Germany with the KTA standards or in the 
USA with the ASME code. The priority will be more to establish equivalence between 
certain specific parts of the various codes and standards. This process has already been 
set in motion and it should be systematically pursued. The next stage would be to draw 
up a manual setting out the full set of codes and standards needed to construct an EPR-
type plant. This would be made up of the various existing codes, which would be 
approved at Community level and be supplemented, where necessary, by codes developed 
at European level or existing codes which have been improved or completed. The 
promoters of the EPR project need to achieve such ambitious objectives. This is for the 
industry to develop, but Community work in codes and standards is essential to a coherent 
overall plan, to support for specific studies and to the guarantee of a European label 
involving the parties concerned in all the Member States. In 1993 the Commission plans 
to commit substantial funding in order to accelerate this process. 
II.Means employed: Consultation and cooperation extended to all parlies involved 
in nuclear safety 
The Council "encourages the Commission, national safety authorities, institutions 
specialized in nuclear safety evaluation, research and development institutions, nuclear 
utilities and manufacturers in the Community to continue to participate actively in the 
well-established and continuing process of consultation and cooperation, in the context 
of the 1975 Resolution". 
Consultation and cooperation are actively pursued in the Reactor Safety Working Group 
(RSWG) which brings together representatives of the safety authorities and their technical 
support organizations, plant operators and manufacturers. Swedish and Finnish experts 
participate in the work of the RSWG as observers. In 1992, at the end of its four-year 
work programme (1988-92) this Group looked at its working methods, the extent to 
which it had completed its activities in the 1988-92 work programme and the new 
directions its work should take for the period 1992 to 1996. 
The Group noted that in terms of working methods high priority had been given to an 
exchange of information on the situation in the various Community countries, on 
significant events as regards safety, and on probabilistic studies and that from this point 
of view the Group provided a unique and active forum in which the safety authorities, 
operators and constructors could share their experiences. The RSWG felt that the use of 
working parties, task forces, study contracts and in-depth discussion of the attendant 
documents made for an effective means of achieving consensual harmonization. It also 
felt that its work should result in more publications. 
The RSWG noted that all the activities scheduled in 1988 had been undertaken and that 
some had been completed; others had to be pursued, notably on existing safety margins, 
severe accidents, probabilistic methods, the principles of safety and codes and standards 
for advanced reactors. These are the areas on which the RSWG thinks it should 
concentrate its efforts for the period 1992-96. This does not represent any great change 
over the previous line of action which took account of the degree of harmonization as 
spelt out in a 1987 consensus document and the effects of the Chernobyl accident on the 
approach to safety, except that it adds general trends, such as the situation of power 
plants in Eastern European countries and the opening of the single market. The trends 
towards more universal safety objectives and criteria to include Eastern European 
countries present an excellent reason for stepping up activities and drawing conclusions 
in key areas such as severe accidents, safety margins evaluation and probabilistic 
methods. 
A brief look will be taken at the main activities undertaken in the previous work 
programme as regards the abovementioned priorities which need to be continued and at 
the new measures resulting from the plan approved in 1992 for the period 1992-96. 
As part of the assessment of safety margins a number of benchmarks provided a set of 
hypothesis and realistic data on the release of fission products and the radiological 
consequences of a design basis accident, i.e. a sudden rupture of a main primary circuit 
pipe in a pressurized water reactor. The same exercise is pursued in the same manner 
for steam generator lube rupture accidents. A new study will be undertaken to evaluate 
existing margins for containment in the event of a severe accident. This will be one of 
the points to be taken into account in an updated report on the management of severe 
accidents. The problem of establishing the ambient conditions of a severe accident to 
important electrical components is currently being studied as part of a benchmark 
exercise. 
As regards probabilistic safety assessments, the RSWG has so far concentrated on 
exchanges of information, especially the PSAs carried out in the Member States. In 
future, the emphasis will be on the harmonization of methods. As regards operational 
safety, following the publication of a consensual report on periodic reassessments 
comparisons will have to be extended to reassessments taking account of the protection 
against earthquakes. The exchange of information will have to be continued on the 
practices of modifying installations. Finally, the important problem of qualifying safety 
software will be broached. 
\ 10 
Advanced nuclear power plants showing what will probably be the first generation of 
future plants are at the hub of studies undertaken within the RSWG. Revolutionary plants 
with different safety features from the current plants are not disregarded - studies have 
been presented and discussed within the RSWG - but the immediate interest centres on 
evolutionary plants developed by extrapolation from present plants with improved safety 
features. One example is the REP 2000 programme launched by EDF which is gradually 
being linked with the Franco-German EPR project. The exchange of information 
currently centres around this project and the initial discussions on the safety principles, 
options and rules taken into account. This project confirms the need for harmonization 
of the manufacture and control codes and standards for the main steel components of 
PWR plants. The Franco-German comparison of practices, codes and standards for the 
manufacture of reactor vessels is a starting point which should be extended to other 
components and form part of systematic harmonization at European level. This will be 
based on pre-normative activities which have been undertaken for some time and will 
continue in the fields of manufacture and in-service inspection, structural mechanics and 
materials of steel components in the primary circuits of plants. 
This is not a complete list, the sole aim being to indicate which points warrant the most 
attention at the present time. While they might seem fairly disparate at first sight, these 
measures are all part of a "jigsaw" which has already been started to be put together, as 
borne out by the previous reports, especially the reports of 6 April 1987 
(COM(87)96 final) and 23 January 1992 (SEC(92)79 final), which will not be returned 
to. The activities of the RSWG tie in closely with the work of the Nuclear Regulators' 
Working Group (NRWG) which consists solely of the safety authorities. 
In general, the activities of the RSWG are upstream of those of the NRWG in which the 
more specifically regulatory aspects are dealt with after the exchange of information and 
establishment of a technical consensus have been handled by the RSWG. However, the 
respective activities of the RSWG and the NRWG should not be classified too rigidly 
since it does not always apply. A vital aspect which has to be stressed in the 
harmonization sought through the network of cooperation and consultation put in place 
by the Commission as part of the RSWG is that harmonisation and search for equivalence 
between the rules and practices of safety are evolutive and iterative processes dependent 
upon - step by step - technological innovation and the results of research. Before looking 
more closely at this aspect of Community action, it should be noted that the Commission 
supports several promotional measures for possible European networks: ENIQ -
European Network for Inspection Qualifications; AMES - Action of Reactor Pressure 
Vessel Materials Irradiation Effects and Studies; NESC - Network for Evaluating Steel 
Components. JRC assumes the coordination of these networks. 
III. Scientific and technical support 
"The Council reaffirms the importance of technological progress in relation to the safety 
of nuclear installations and in this connection invites the Member States and the 
Commission to continue and intensify concerted effort through significant joint actions on 
key safety issues. Thus it underlines the primary importance of nuclear safety research 
and technological innovation and the need to continue and increase action undertaken 
within the Community, including the study of future generations of reactors. This action 
may, where possible, be extended to third countries, notably those of Central and Eastern 
Europe and the Republics of the former Soviet Union." 
The safety practices, rules and criteria applied to plants in service were established from 
the outset on the basis of technical knowledge available at the time. This technical 
knowledge generally came from results of research programmes set up to identify the 
physical phenomena at stake, which were complex more often than not, particularly in 
the case of accidents. Accidents to be taken into account in the design of an installation 
were defined as design basis accidents to cover all situations. Where the available 
knowledge seemed insufficient or uncertain, margins of conservatism varying in size were 
introduced into the Regulation. 
This situation changed with the results of a number of research programmes, but it was 
the TMI 2 accident in 1979 which finally called into question the concept of design basis 
accident and led to new research programmes designed to assess existing margins in 
respect of more serious accidents than the design basis accident. 
Concertation and collaboration undertaken in order to promote the harmonisation of 
approaches to safety means, as seen above, that a consensus among the bodies represented 
in the RSWG has to be reached and should result in the recognition of equivalence 
between different options. This kind of consensus, or, where possible, the establishment 
of common rules, can only be obtained when the scientific basis, e.g. detailed knowledge 
of physical phenomena, knowledge of material properties and increasingly sophisticated 
methods used to assess and analyze safety are themselves the result of a consensus. At 
the end of the 1980s a large number of major research programmes on reactor safety were 
nearing completion in the United States and Europe (LOFT, LACE, MARVIKEN, ACE, 
BETA, PHEBUS SFD, LOBI, etc.) and budgetary restrictions limited major new projects 
to a few rare experiments such as PHEBUS PF (fission products) in France, with 
participation and financial backing from the Commission and FARO at the JRC Institute 
for Safety Technology in Ispra. The Commission was thus aware that extra experimental 
work still had to be done and that there was still much to do to make better use of many 
results already available in the Member States and ensure their use at technical and 
regulatory level. Accordingly, a reinforced concerted action programme on reactor safety 
was proposed in 1990 and accepted by the Council on 28 November 1991. Later on this 
programme was open to the participation of Central and Eastern European Countries 
(PECO). The general theme of this action is the containment of radioactivity in the event 
of severe accidents and the eight projects implemented cover the following three aspects: 
accident progression analysis; behaviour and qualification of the containment system; and 
accidents management and control. Within each project the method of work consists of 
concertation on the latest scientific results obtained in national or Community programmes 
which are pooled, analyzed and evaluated jointly. The funds made available for each 
project will make for a certain amount of extra experimental work. The final objective 
of this reinforced concerted action programme will be to contribute on a certain number 
of key safety issues to the establishment of scientific and technical consensus. Examples 
are the "hydrogen", "source term" and "molten fuel-coolant interactions" projects which 
ought to clarify a number of uncertainties surrounding the risk of detonation of hydrogen, 
the problems of the retention of fission products in the containment system and the risk 
of steam explosion. These are three issues which could be tackled as part of the 
consultation and cooperation procedures within the RSWG to harmonize safety practices 
and rules where the point in question, for example, is the problem of managing severe 
accidents or taking account of available safety margins for confinement systems to cope 
with the shock waves caused by steam explosion or hydrogen detonation. This illustrates 
the close links between the technical and regulatory activities of the Commission and 
nuclear safety. It should be noted, however, that despite the significant efforts made at 
Community level and at a broader international level, as in the CSNI of the NEA 
(OECD), the funds set aside for nuclear safety research have constantly dropped both at 
national and at Community level. This is a worrying situation and the political powers 
keep ignoring the pressing appeals made within the respective fora, in particular the STC 
(Euratom Scientific and Technical Committee), by the specialists concerned. 
The safety of future nuclear power plants is at the centre of a debate generated by the 
Chernobyl accident on the future of nuclear energy. To counter the pessimism reigning 
in nuclear circles, suppliers and electrical utilities have taken a serious look at how to 
improve proven concepts or how to develop new, more innovative concepts. The main 
concern was to improve safety and, contrary to what had happened in the 1960s in the 
development of LWR systems, the basic safety requirements and options formed the 
foundation for the new solutions proposed. Thus, technological innovation put itself 
primarily at the service of safety. In recent years, the Commission has closely monitored 
these developments and has assigned various studies in which the safety aspects of the 
main projects in progress were examined. The RSWG has also been kept regularly 
informed by the operators and constructors of the specifications and orientations in the 
EPR project. 
Following the political upheavals in Eastern Europe and the former Soviet Union and the 
West's realization of the problems presented by the safety of nuclear power stations in 
those countries, one of the main concerns of the Council and the Commission was for the 
urgent practical assistance provided by the Community under the PHARE and TACIS 
programmes to be accompanied by a real transfer of the approach to safety, methods, 
practices, rules and criteria applied by the Community to help the countries of the East 
gradually to bring the safety of their installations up to an equivalent level to that of 
European installations. The Commission, which does not wish to limit this objective 
solely to existing plants but also to future generations of plants, has recently taken 
significant steps in this direction, in the form of a joint study between, on the one hand, 
the constructors and technical support organizations for the Community's safety 
authorities, as coordinated by EDF and GRS respectively, and, on the other, their Russian 
counterparts. This is a joint Community-Russian study of how to improve safety in the 
main reactor systems, the principal objective being to identify joint measures which could 
help to accelerate this improvement and have an impact on the future of nuclear energy 
in Europe. This analysis will also provide support for a vast operation of technological 
transfer to the Russian industry, safety assessment establishments and research and 
development institutes so that European know-how can help future Russian projects. 
Technological innovation and the results of research obtained in the Community form an 
integral part of this transfer of know-how. The project will last for a period of around 
three years and is thus a major operation involving about 25 manyears from each side 
(Community and Russia) for the two parts of the analysis. In the first part - "Evolution 
of safety requirements for nuclear power plants" - the safety objectives and practices will 
be identified for a period of some 20 to 30 years and in the second part - "Challenges and 
solutions" - the areas will be pinpointed in which such developments and initiatives can 
be expected. 
* t3 
IV. Translation of efforts into regulations 
"The Council requests the Member States to continue - with an active contribution from 
the Commission - to ensure greater concerted effort between the national safety 
authorities in the Community on safety criteria and requirements and on the incorporation 
of the conclusions reached into the practice followed in the Member States, in order to 
arrive at a system of safety criteria and requirements recognized throughout the 
Community, " 
The Commission's policy of harmonizing safety requirements, criteria and rules at the 
beginning of the 1970s, as borne out by the Resolution of 22 July 1975 on the 
technological problems of nuclear safety, is based on systematic cooperation and 
concertation with the parties responsible for nuclear safety in the Member States through 
working parties set up by the Commission. The activities of the Reactor Safety Working 
Group (RSWG) were described briefly above; the other, the Nuclear Regulators' 
Working Group (NRWG), consisting solely of national regulatory, licensing and control 
authorities, pursues the ultimate objective of this cooperation and concertation, viz. 
recognition at Community level of a set of safety criteria, rules and requirements. 
Representatives of the safety authorities of Finland and Sweden also participate as 
observers, as for the RSWG, in the work of the NRWG. The principal results obtained 
are described in the document COM(88)788 final of 24 February 1989 entitled 
"Assurance of the safety of nuclear power plants". The work of the NRWG and the 
RSWG has in the past been closely linked and the work programmes set up by the two 
parties have gone along parallel lines. For some years now, as a result of external factors 
and in particular the development of relations with the Safety authorities of the countries 
of Central and Eastern Europe and the former Soviet Union, which will be discussed in 
more detail below, and also the internal factor of establishing a consensus on a growing 
number of subjects, the influence and image of the NRWG has gradually been enhanced. 
In 1992 the methods and work programme of the Group were discussed and redirected. 
In an effort to avoid any confusion between Community harmonization and the problem 
of induced responsibilities, the Group stressed the following principles: 
-The safety of nuclear installations must remain the responsibility of the individual 
countries, meaning that there must be a legal framework to regulate nuclear activities and 
designate responsibilities: the principal responsibility for the safety of an installation must 
lie with the operating organization. 
-The safety regulator is responsible for monitoring and implementing the safety objectives 
in accordance with the laws and regulations. 
The current work programme, some of the main points of which will be indicated as 
examples, leaves more scope than in the past for the final phase of harmonization, which 
is to establish consensus on the points which have led to detailed technical discussions 
upstream and in particular in the RSWG. It also takes a systematic approach to general 
problems which at the outset concern only the safety authorities or which refer to how the 
public authorities organize the safety of installations. The working method employed by 
the NRWG makes consistent use of studies financed by the Commission and sets up 
meetings of specialist task forces which draft questionnaires for safety authorities, process 
the results and make summaries in the group itself. Attention is drawn to the following: 
-Periodic reviews of the safety of nuclear plants have given rise to work, the first stage 
of which was to make an inventory of practices while stressing differences in approach. 
^ 14-
At this stage, particular attention was paid to the work carried out by the IAEA in the 
same field. The second stage provides for the drafting of a consensus document restricted 
to the essential points. 
-Regulatory actions concerning probabilistic safety analysis has been initiated and a 
summary made by a consultant on the basis of replies to a questionnaire will be examined 
by a task force with representatives from seven European countries. The aim is to 
establish to what extent the results of PSAs can be taken into account in authorization 
procedures for the entire lifespan of the plant. The task force will also take account of 
work done by the IAEA and the OECD-CSNI on the same subject. 
-The influence of the regulatory authorities on the design of future plants is an actual 
topic, as was seen above in the EPR project. The authorities lay down what safety 
objectives are to be achieved, and then it is for the plant operators and/or constructors to 
draw up detailed criteria and standards; the latter must also demonstrate to the authorities 
that the safety objectives set out at the outset are met, although what needs to be known 
is how and by what procedures the proposals from operators or constructors are to be 
submitted and accepted by the safety regulators. The NRWG has started to tackle this 
problem along these lines without losing sight of OECD-CNRA activities. 
The NRWG has started an in-depth study into the practices and approaches followed in 
the Member States on "safety culture". A first point was to see how the Member States 
understand this concept and thus how they apply the fundamental principles of safety. 
This will be followed by a discussion of current practices by way of a dialogue between 
safety authorities and operators and the implementation of "safety culture" by operators. 
Work more closely linked with the principles, criteria, codes and standards of safety has 
been undertaken on the application of safety principles to the design of safety systems. 
The work concentrates on the application of single failure, diversity and reliability criteria 
to the design of two PWR safety systems chosen as examples: the auxiliary feedwater 
system of steam generators and the emergency core cooling system, the aim being to 
obtain information on how these criteria are interpreted and applied by the various safety 
authorities. This operation is run in close connection with a series of exercises to 
compare the safety rules applied for the design of three modern PW^R plants: Sizewell B 
(UK), Konvoy (Germany) and N4 (FR) launched within the RSWG. 
These examples demonstrate the efforts made to incorporate into the procedures and 
practices of the Member States the results of harmonizing safety criteria and requirements 
obtained by the Commission and the Member States within the NRWG. The close links 
which now exist between the safety authorities of the Member States and the countries of 
Central and Eastern Europe and the former Soviet Union are discussed below as part of 
cooperation with Eastern European countries. Efficient and consistent transfer to these 
countries of the "safety culture" and the system of methodologies, requirements, rules and 
criteria involved will not be possible unless this system is recognized and applied 
throughout the Community. 
V.Cooperation with the countries of Eastern Europe 
"The Council emphasizes the particular importance it attaches to nuclear safety in Europe 
and therefore requests the Member States and the Commission to adopt as the 
fundamental and priority objective of Community cooperation in the nuclear field, in 
particular with the other European countries, especially those of Central and Eastern 
Europe and the Republics of the former Soviet Union, that of bringing their nuclear 
installations up to safety levels equivalent to those in practice in the Community and to 
facilitate the implementation of the safety criteria and requirements already recognized 
throughout the Community. " 
The contacts established at the end of 1990 between the safety authorities of the 
Community Member States, Finland and Sweden, as represented in the NRWG, and their 
counterparts in the countries of Central and Eastern Europe and the former Soviet Union 
rapidly led to the setting up by the Commission in 1991 of the CONCERT (Concertation 
on European Regulatory Tasks) Group for the purpose of developing cooperation between 
the safety authorities in the Community and in Eastern Europe, the objective being to take 
advantage of the existence of the concertation structures built up in Western Europe in 
the NRWG in order to improve cooperation. The three areas proposed for joint work 
were as follows: regulatory bases and procedures, regulatory aspects of technical and 
operational problems, and assistance programmes in progress. The intention was through 
the CONCERT Group to provide a broad European framework for regulatory matters, 
with a general remit. The Group's first decision was to prepare a document based on the 
work of a task force and a consultant setting out the objectives of nuclear safety and the 
principles on which an effective regulatory regime should be based. This document, 
entitled "Objectives and requirements of a nuclear safety regime", is intended to help the 
Eastern European countries set up adequate regulatory structures. 
It rapidly emerged that one of the essential objectives of assistance tor the Eastern 
European countries in connection with nuclear safety was to transfer to these countries 
the organizational, procedural and regulatory experience collected in the Community. At 
the beginning of 1992, at the instigation of the NRWG, the Commission set up, in support 
of the CONCERT structure, the RAMG (Regulatory Assistance Management Group) 
made up of the safety authorities participating in the NRWG prepared to provide support 
for their counterparts in Eastern Europe in the framework of technical assistance 
programmes funded by the Community. The RAMG supervises assistance activities and 
advises the Commission on proposals made in this connection. More particularly, the 
RAMG's task is to define, organize and implement support for the regulatory authorities 
in the countries of Central and Eastern Europe and the former Soviet Union, help the 
Commission in the establishment of a regional assistance programme for these countries, 
advise it on requests from the recipient countries so as to maximize the benefits, and 
examine and evaluate the results of the assistance programmes. 
On the basis of this two-tier consultative structure, consisting of CONCERT, in which 
the broad policy options are discussed by all the authorities, and the RAMG, in which the 
safety authorities of the member countries of the NRWG prepared to get involved in the 
assistance programmes discuss practical measures, the Commission has established a 
consistent concertation and cooperation system for all matters concerning the regulatory 
aspects of nuclear safety. The assistance programmes funded by the Community (PHARE 
and TACIS) benefit directly from the advice and suggestions emerging from the 
cooperation established in this structure, and in order to formalize it the Commission has 
drawn up a Memorandum of Understanding spelling out the respective roles of the 
CONCERT Group and the RAMG. 
The Memorandum of Understanding specifies the type of measures to be carried out on 
the basis of contractual links between the Community, with the agreement of the safety 
authorities in the recipient States, and the Community bodies taking part in the assistance 
programmes. Among the measures carried out, mention should be made of "exploratory 
missions" to prepare the assistance measures by helping the recipient countries to identify 
and formulate their regulatory requirements. These missions are proposed by the RAMG 
at the request of interested countries. For each mission a representative of a 
Member State's safety authority is designated as coordinator and spokesman vis-à-vis the 
recipient country's safety authority, and several experts from other Member States 
together with the coordinator form the team which goes to the spot to examine specific 
problem raised by the applicant State. A report based on the opinions formed during the 
mission and on the discussions held with the regulatory body visited sets out 
recommendations and identifies the successive measures proposed. The measures are 
subsequently incorporated into the Commission's assistance programme following 
consultation with the RAMG. The Community organizations which take part in the 
exploratory missions are the safety bodies which draw up proposals for licences and/or 
regulations, assisted in certain cases by the technical organizations providing support for 
the safety authorities (TSOs - Technical Safety Organizations), e.g. CEA-IPSN in France 
where the safety authority is the DSIN (Industry Ministry), GRS in Germany where the 
safety authority is the BMU. So far, exploratory missions have been carried out in 
Lithuania, Ukraine, Russia, Hungary, Bulgaria and the Czech and Slovak Republics. 
Strictly speaking assistance projects are carried out by groupings of several "safety 
authority" bodies or for assistance relating to specific safety evaluations by groupings of 
several technical support organizations. It will be noted that the final objective set by the 
Council is to endeavour to bring the nuclear installations in the countries of Central and 
Eastern Europe and the former Soviet Union up to safety levels equivalent to those in 
practice in the Community. As far as strictly regulatory matters are concerned, this 
objective is twofold and the prospects of success are not identical in each case. Providing 
assistance to the safety authorities involves (a) transferring a system of principles, criteria, 
safety rules and evaluation methods and (b) transferring practices, regulations and laws 
concerning the organization of the public authorities for the approval and control of 
nuclear installations. 
As far as the first point is concerned, the beneficiaries of the assistance programmes are, 
within the body representing the safety authority, and whatever the country in question, 
safety specialists with whom technical collaboration has been effectively established and 
who are convinced of the need for a more extensive technical regulatory arsenal. As far 
as the second point is concerned, the beneficiaries are always the same and they are no 
less convinced of the need to establish governmental structures guaranteeing independence 
vis-à-vis the political and economic authorities for those with technical responsibility for 
safety, but they are not the only ones since ultimately they have to persuade the 
authorities in question to accept administrative and financial changes. The difficulties 
encountered in this respect have been emphasized by certain representatives of the Eastern 
European countries on a number of occasions during exploratory missions, in particular 
the representatives of the countries of the former Soviet Union during the meeting of the 
CONCERT Group held in Brussels in December 1992. 
1? 
On the sidelines of this meeting a seminar was held on the "legal framework for nuclear 
safety" and the problems presented by the creation from scratch in the countries of 
Eastern Europe of a complete legal framework, or simply adjustments to the legal 
framework or to the existing administrative framework, were raised and the pessimism 
of certain delegates was noted. Generally speaking, it has to be acknowledged that the 
transfer of the regulatory know-how acquired in the Community to the safety authorities 
of the recipient countries is progressing satisfactorily at a technical level and the pressure 
exerted by the West Europeans is appreciated by their counterparts in Eastern Europe. 
However, this transfer on a technical level will not be fully effective unless there is also 
strong political pressure to ensure that the changes needed to the legislation and the 
administrative structures of the States concerned are implemented: the transmission by 
the Commission of the reports of the exploratory missions approved by the RAMG to the 
highest governmental bodies of the State concerned is a first step in the right direction. 
The first meeting of the CONCERT Group outside Brussels was held in Moscow in 
April 1993. Apart from its contribution to preparing the Community assistance 
programme and monitoring its implementation, the Moscow meeting enabled a very open 
discussion to be held on the delicate matter of "periodical safety reviews" and thus help 
to further the essential aim of the Group, viz. establishing a mechanism for long-term 
pan-European cooperation. This discussion was based on a study funded by the 
Commission concerning practices in this connection in Western Europe. The oldest 
power stations in particular are concerned. 
VI. International cooperation 
"The Council encourages the Member States and the Commission to act in a coordinated 
manner in international fora on the basis of the achievements reached in the Community 
towards a system of internationally accepted nuclear safety criteria and requirements, in 
particular in the framework of the International Atomic Energy Agency (IAEA)." 
While collaborating actively with the IAEA and with the CNRA (OECD-NEA), the 
Commission is endeavouring to help the Community Member States reach common 
positions in the framework of these international organizations so that Community 
achievements are taken into account wherever possible at a wider international level. 
It should be recalled that at the general conference of the IAEA in September 1991 a 
number of general objectives were set: to implement a harmonized international approach 
to all aspects of nuclear safety, to prepare the ground for an international convention on 
nuclear safety, to develop a common basis on which to judge the acceptability of the 
safety of power stations built in accordance with old criteria, to consider a complete and 
transparent process with regard to safety with the aim of achieving a high level of safety 
in all nuclear installations in operation, and to set up a group of experts to develop safety 
principles for the design of future power stations. Work on the international convention 
has begun at the IAEA and it would seem that in the first instance a separate protocol on 
the safety of nuclear power stations will be drawn up. 
On a number of specific topics, the activities carried out within the IAEA and the OECD 
are closely connected with the activities of the Commission's RSWG and NRWG. 
Mention should be made in particular of the revision of certain NUSS codes, the 
incorporation of the NUSS codes into national regulations, the IAEA-INSAG-4 report 
18 
on safety culture, the IAEA's fundamental safety principles, and the work of the 
CNRA-OECD on the safety requirements of future power stations and that of the 
CSNI-OECD-NEA on safety-related R&D activities. All these matters are discussed in 
detail in Community fora, and the conclusions are taken into account to a very great 
extent by the Member States' representatives when they attend IAEA and OECD 
meetings. 
There is active direct cooperation between the Commission and the IAEA with regard to 
the safety of installations in the countries of Central and Eastern Europe and the former 
Soviet Union. The Commission takes part, with its own experts, in the OSART and 
ASSET missions organized by the Agency in these countries and funds the participation 
of experts from Community Member States. Likewise, the Agency is invited to 
participate as an observer in the activities of the CONCERT Group. 
VII. Trends, assessment and objectives of the Commission's activities 
The Council Resolution of 22 July 1975 committed the Member States and the 
Commission to a gradual process of harmonizing safety practices and rules in the 
Community. The Resolution of 18 June 1992 updates and strengthens the Community's 
role in the light of one of the key aspects of safety, namely the awareness at the end of 
the 1980s of the existence of a small but not negligible probability of severe accidents 
which could have repercussions worldwide. In addition, while confirming the Community 
objectives set out in the 1975 Resolution, it stressed the need to transfer to and promote 
acceptance by the countries of Central and Eastern Europe and the former Soviet Union 
of the know-how and experience acquired at European Community level. At the 
beginning of 1993 it can be said that the first steps taken towards achieving the latter 
objective are going in the right direction. With regard to the measures carried out since 
1975 at Community level, it has to be acknowledged that in a climate largely adverse to 
the development of nuclear energy, the harmonization of nuclear safety practices and rules 
is progressing satisfactorily in Europe. In this connection, it is worth examining in closer 
detail the development of cooperation and concertation between the parties involved in 
nuclear safety, and in particular the safety authorities, the nuclear utilities and the 
constructors. 
In the 1970s the beginnings of Community activities relating to the safety of installations 
were slow and difficult: the Member States were more inclined to complete their 
plant-construction programmes without having to worry about the constraints which 
would have been placed on them by rigorous harmonization at Community level. The 
1980s saw concertation take a more systematic and active direction. The TMI accident, 
which sparked off a revival in nuclear safety research programmes, provided an impetus 
for greater international cooperation on research, entailing better concertation between 
those responsible for safety in the Member States. At the end of the 1980s, bilateral 
cooperation agreements were concluded between France and the Federal Republic of 
Germany involving research centres and plant constructors (Siemens-Framatome), 
operators and safety authorities or their technical support organizations 
(GRS-CEA-IPSN). With the development of a joint plant project (EPR) and the 
establishment of European specifications (EUR - European Utilities Requirements) and 
the prospects opened up by the Single European Market of 1993, this bilateral cooperation 
had a certain knock-on effect from which, as has already been seen above, the activities 
at Community level relating to the harmonization of safety practices, rules and criteria 
have already benefited and will continue to benefit. 
At the end of the 1980s the Chernobyl accident had major repercussions for the 
development of Community nuclear safety activities. Awareness of the interdependence 
between the future of nuclear energy in the West and the safety of installations in the East 
has encouraged greater cohesion between the parties involved in safety in the Community 
who have gradually regarded themselves as having joint responsibility vis-à-vis their 
counterparts in the countries of Central and Eastern Europe and the former Soviet Union. 
The recent political upheavals in these countries, resulting in the establishment of major 
Community assistance programmes (PHARE and TACIS) have sparked off a revival in 
intra-Community cooperation and concertation. The assistance projects launched since 
1991 are more often than not projects to evaluate the situation, analyze safety and 
improve control and safety systems. To meet a very considerable demand and provide 
the recipient countries with consistent assistance offering all the necessary safety 
guarantees, the Commission has encouraged groupings of European bodies providing the 
assistance: nuclear utilities (TPEG), safety authorities (RAM) and their support 
organizations (TSOs), and plant constructors (ENAC). Depending on the case in point, 
the group includes the bodies in the interested Member States belonging to a given 
category, e.g. the safety authorities or the TSO, and in other cases for example for 
certain industrial projects implemented under the TACIS 1991 programme the group only 
includes some of the parties or is made up of a limited number of plant suppliers or 
electrical utilities acting jointly on their own initiative. This type of collaboration is 
extremely fruitful and since ultimately it is a question of dealing with safety problems the 
projects carried out provide the European organizations with a unique opportunity for a 
joint practical harmonization exercise. While all the activities launched by the 
Commission with the help of the RSWG and the NRWG are aimed at the harmonization 
at European level of safety practices and rules through a more or less abstract process of 
discussion and comparison of national positions, the implementation of assistance projects 
gives the same organizations, which also participate actively in the activities of the RSWG 
and the NRWG, an opportunity to apply in practice the results of Community cooperation 
for the benefit of the recipients of the assistance. The resulting concertation and 
operation established in a very practical way between the parties jointly responsible for 
a given project can ultimately only benefit the Community activities, the success of which 
is indirectly furthered by the assistance programmes. 
In this context favourable to the Commission's desired policy, in the wake of the work 
carried out jointly in the context of the EPR project, the EUR specifications and the 
assistance programmes, there is likely to be a knock-on effect at Community level, 
gradually prompting the safety authorities in the Member States, the TSOs, the electrical 
utilities and the plant suppliers to discuss and reach a consensus on the specific safety 
problems raised in the Member States with regard to operational safety and licensing 
problems. This would strengthen cohesion and solidarity between those responsible for 
safety within the Community and would contribute to greater public acceptance of nuclear 
energy. 
Following on from this examination of the various aspects of Commission activities in the 
field of reactor safety, it would seem to be useful to examine them in relation to the 
general objectives pursued since 1975, in the light of the 1975 Resolution which advocates 
the establishment of a safety system recognized throughout the Community which is 
capable of ensuring a satisfactory standard of protection for the public and the 
• to 
environment against the risks arising from the use of nuclear energy. 
This fundamental objective has gradually been achieved since 1975 in three areas: the 
organization of safety, particularly as regards the public authorities, the safety evaluation 
methods, and the technical regulations. 
This is no place to go into the details of what the Community has achieved since 1975. 
Numerous progress reports have given an account of the matters on which a consensus 
has been reached. However, the following is a tentative assessment: 
-With regard to the organization of safety, the achievements are very considerable, and 
the recent report already mentioned above, entitled "Objectives and requirements of a 
nuclear safety regulatory regime", which could be supplemented and improved, gives a 
fairly complete overview of the principles on which there is a European consensus. 
-As regards the safety evaluation methods, the report COM(88)788 entitled "Assurance 
of the safety of nuclear power plants - Objectives and methods" will also constitute a 
virtually complete consensus document once it has been updated to take account of the 
question of severe accidents. 
-Where technical regulations are concerned, the situation is complex because of the 
various hierarchies of regulations, necessitating in some cases initiatives on the part of 
industrial operators, and in view of the very broad range of problems to be taken into 
account in the various phases of the existence of a power station, namely site selection, 
design, commissioning, operation and decommissioning. The 1981 document entitled 
"Safety principles for light-water-reactor nuclear power plants" (COM(81)519 final) 
represents an important milestone, however, by listing the fundamental principles and the 
general safety principles recognized at Community level, and mapping out future activities 
relating to safety requirements as well as codes and standards. 
The 1998 document entitled "Assurance of the safety of nuclear power plants - Objectives 
and methods" indicates that the safety levels achieved in the Community countries are 
practically equivalent, while indicating the areas, essentially severe accidents, where 
progress still needs to be made. 
At present, with reference to power stations in operation or planned, it can be said that 
considerable progress has been made. Listing the points which over the next four years 
will comprise the revised work programme of the RSWG and NRWG will give some idea 
of what remains to be done to establish a safety system recognized throughout the 
Community. 
Over these four years, efforts should focus in particular on the following areas: 
-Codes and standards: practical application of the safety codes (NUSS-IAEA); industrial, 
manufacturing and control codes - the work carried out in conjunction with the EPR 
project will make it possible to identify the needs where the development of specific 
standards is concerned; and the certification of components. The certification of safety 
software will be covered separately. 
-Evaluation of safety margins: problems concerning the bursting of steam generator tubes 
and the resistance of containment systems should be studied in greater detail. 
-Severe accidents: attention will focus on the management of accidents and on realistic 
source term and containment performance evaluations. 
-Probabilistic studies: the taking into account of probabilistic analysis methods in the 
regulatory process will be examined in close connexion with the activities carried out by 
the JRC in this area. 
-Operational safety: safety reviews and practices relating to the modification of 
installations should result in a consensus document. 
-Safety principles: the problems raised by their practical application will be examined. 
However complete it may be, the safety system gradually established following a complex 
process of consultation, discussion and concertation which has been conducted for more 
than 20 years will not bring this process to an end. 
Absolute safety is as Utopian an objective as absolute health, since safety can always be 
improved on, and at a time when technological progress is being made constantly 
improving safety must be a permanent objective for the responsible authorities, which 
must ensure that adequate resources are available and used wisely. Community 
concertation in relation to existing installations should take research results into account 
as long as there are objective reasons to continue with the research. As regards future 
generations of power plants, technological innovation should always be examined from 
the point of view of safety and be designed promote safety. 
Over and above the safety system being established, the ultimate objective will be to 
achieve a genuine Community safety culture progressing throughout Europe. 
XI 
ISSN 0254-1475 
COM(93) 649 final 
DOCUMENTS 
EN 15 05 
Catalogue number : CB-CO-93-705-EN-C 
ISBN 92-77-62707-7 
Office for Official Publications of the European Communities 
L-2985 Luxembourg