The first and most important issue in establishing a new nuclear power program is trust; trust that is earned, deserved, and maintained by all people in the industry. The single, most corrosive factor in relationships between the industry and the public is a lack of trust. If all stakeholders of this enterprise within any nation can establish and retain a high level of trust­worthiness, public acceptance will not be a problem. Energy supply is a very public business, and consequence is very easily linked to the root cause of negligence. A successful nuclear operating organization promotes truthful and open interaction with its staff and with the public — nothing is hidden.

A. J. GONZALEZ, Autoridad Regulatoria Nuclear de Argentina (Argentine Nuclear Regulatory Authority), Argentina

Abstract: The international radiation protection system for nuclear power plants (NPPs) is described. It includes the estimates of the United Nations Scientific Committee on the Effects of Atomic Radiation, the recommendations from the International Commission on Radiological Protection, and the safety standards established by the International Atomic Energy Agency. The aim is to summarize the sytem’s fundamental principles. Their application to potential exposures (and therefore to nuclear safety) is portrayed including a compliance criterion for prospective probabilistic safety assessments. Practical considerations on occupational and public protection are discussed, including a description of the latest assessments of the radiological consequences of the Chernobyl accident.

Key words: radiation safety, radiation protection, nuclear safety, safety assessment, nuclear regulation.

11.1 Introduction

Ionizing radiation (named, in short, radiation) is perceived to be the nemesis of nuclear energy. This is unsurprising: radiation exposure is detrimental to human health and omnipresent in activities and installations of the nuclear fuel cycle, including regulated nuclear power plants (hereinafter termed NPPs) for electricity production. These installations routinely discharge into the atmosphere and watercourses, gases, aerosols and liquids contain­ing small amounts of radioactive substances, which may cause radiation exposure to members of the public; their operators are occupationally exposed to radiation delivered by ubiquitous radioactive materials in work­places. NPP safety assessments demonstrate that the likelihood of a cata­strophic accident is exceedingly small; however, should a nuclear accident occur its consequences can be severe: emergency workers may be exposed to high radiation levels and large amounts of radioactive materials can be uncontrollably released into the environment, contaminating vast territo­ries and exposing large populations. NPPs also generate large amounts of radioactive waste that have to be transported over public places and which are viewed as a radiation exposure legacy for our descendants.

Decommissioning activities, necessary for the termination of nuclear opera­tions, may leave radioactive residues that will likely remain in the habitat. Ultimately, concerns have been growing on the security of the radioactive materials in the nuclear fuel cycle since their malevolent use might cause serious radiological harm.

Predictably, the protection against radiation exposure, namely radiation protection (sometimes termed radiological protection), has become a sine — qua-non condition for the justification of nuclear power.

The protection against radiation exposure has been fully internatio­nalized and the current radiation protection rests on four international foundations:

1. The estimates of radiation levels and effects are assessed by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). UNSCEAR is an intergovernmental scientific body founded in 1955 and since reporting radiation levels and effects to the United Nations General Assembly (UNGA) (UNSCEAR, 1958, 1962, 1964, 1966, 1969, 1972, 1977, 1982, 1986, 1988, 1993, 1994, 1996, 2000, 2001, 2009, 2011).

2. A radiation protection paradigm is recommended by the International Commission on Radiological Protection (ICRP). ICRP is a scientific non-governmental independent charity, i. e., a non-profit-making orga­nization, providing advice on radiation protection (ICRP, 1951, 1955, 1957, 1959, 1964, 1966, 1977, 1978, 1985a, 1985b, 1991, 2007a). It was established in 1928 by the International Congress of Radiology, with the name of the International X-Ray and Radium Protection Committee (IXRPC) (IXRPC, 1928, 1934), following a decision by the Second International Congress of Radiology, and in 1950 it was restructured and renamed as now.

3. International standards on radiation safety are established under the aegis of the International Atomic Energy Agency (IAEA) (IAEA, 1960, 1962, 1967, 1976, 1982, 1996a, 2011), lately in co-sponsorship with other relevant intergovernmental organizations within the United Nations (UN) system, therefore becoming the de facto international radiation protection authority. Since its creation in 1957, the IAEA has been responsible for safety-related functions that are precisely described in its Statute, namely (1) establishing standards of safety for the protection of health against the detrimental effects attributable to radiation expo­sure; and (2) providing for the application of those standards at the request of any State.

4. Global provisions for the implementation of radiation safety standards, through mechanisms put in place by national agencies and by the IAEA and other international organizations.

On the basis described heretofore, this chapter will explore the interna­tional approach for radiation protection at nuclear activities in general and the nuclear fuel cycle and its NPPs in particular. Its aim is to provide guid­ance on the fundamental principles on which appropriate radiation protec­tion can be based rather than a regulatory text. International radiation protection trends and achievements have been reviewed at the recent 12th Congress of the International Radiation Protection Association (IRPA): Strengthening Radiation Protection Worldwide: Highlights, Global Perspective and Future Trends (IAEA, 2010; Gonzalez, 2009a).

The chapter will not review a number of issues closely related to radiation protection and NPPs, inter alia the following:

• The radiological security of radiation sources at NPPs and of the NPP itself, a subject for which there are detailed recommendations from ICRP (ICRP, 2005a) and which has been amply reviewed by the IAEA (IAEA, 1999b, 2000a, 2001, 2003a, 2006c) and by the author (Gonzalez, 1999a, 1999b, 2001b, 2003a, 2006)

• The radiation protection aspects of waste and spent fuel management, an issue that is discussed separately in Chapter 14, for which there are several recommendations from ICRP (ICRP, 1985b, 1997a, 1998) and which has been thoroughly discussed globally, mainly at the IAEA (IAEA, 2003d; Gonzalez, 2000, 2003c), and is regulated by an interna­tional convention (IAEA, 1997)

• The radiation safety of the transport of nuclear and other radioactive materials associated with nuclear fuel cycle operations, an activity that is heavily regulated globally by standards (IAEA, 2008b, 2009) consti­tuting a real international regime (Gonzalez, 2004a) and for which there is a global consensus (IAEA, 2004a)

• The radiation legacy from the termination of NPP operation and the consequent decommissioning, and also from accidents, a subject to be discussed in Chapter 24, which has been the subject of intense IAEA activity (IAEA, 2003c, 2007) and ICRP recommendations (ICRP, 2009a) but which still lacks an international regime (Gonzalez, 2003d)

• Last but not least, the radiological consequences of NPP accidents (except the Chernobyl accident, which will be briefly covered hereinaf­ter), and the protection of people in emergencies, a subject covered by ICRP (ICRP, 2009b), as well as emergency planning and preparedness, a subject that will be treated in Chapter 12.

Arrangements for emergency plans are carried out in several emergency planning zones that are roughly circular around the facility. The on-site emergency zone is the area surrounding the facility within the security perimeter. It is the area under the immediate control of the facility or opera­tor. The off-site emergency zone is the area beyond that under the control of the facility operator in which intervention could be needed for emergen­cies resulting in major off-site releases or exposures. The level of planning will vary depending on the distance from the facility.

The off-site emergency zone is usually divided in two subzones. The precautionary action zone is a pre-designated area around the facility where urgent protective action has been pre-planned and will be imple­mented immediately upon declaration of a general emergency, to substan­tially reduce the risk of severe deterministic health effects by taking protective action within this zone before or shortly after a release. The urgent protective action planning zone is a pre-designated area around the facility where preparations are made to promptly implement urgent pro­tective action based on environmental monitoring data and assessment of facility conditions, the goal being to avert doses specified in international standards.

Figure 12.1 shows a conceptual distribution of the emergency planning zones around a nuclear power plant.

12.1 Emergency planning zones.

Milestone 1

In response to developments in the 1990s (e. g., Iraq’s clandestine nuclear weapons programme, South Africa’s nuclear weapons programme), the IAEA developed and implemented additional, strengthened safeguards

47 Paragraph 84 of INFCIRC/153 (Corrected) provides the IAEA with the right to conduct a portion of the routine inspections without advance notice. Under such a safeguards agreement, unannounced inspections are carried out in accordance with the principle of random sampling.

measures. Part of the strengthening measures approved by the IAEA Board of Governors and complementary to the safeguards agreement with a State is the ‘Model Protocol Additional to the Agreement(s) between State(s) and the International Atomic Energy Agency for the Application of Safeguards’ (INFCIRC/540 (Corrected)) (IAEA, 1997a). Following the IAEA Board of Governors approval in May 1997, the IAEA began con­cluding with those States that already had a safeguards agreement an addi­tional protocol based on the provisions of a standard reproduced in INFCIRC/540 (Corrected).

When an AP is in force in a NNWS, the relevant articles of the AP oblige the State to provide additional information to the IAEA beyond that required under a CSA. The State’s submissions are referred to as AP dec­larations. In very general terms, the AP declarations articulate all nuclear fuel cycle-related activities and facilities in the State (e. g., nuclear research and development not involving nuclear material, mining and milling), thereby going beyond the information required by the CSA (which is essen­tially focused on nuclear facilities and nuclear material). Beside the avail­ability of broader information concerning a State’s nuclear fuel cycle, the implementation of an AP in a State also permits the IAEA to access loca­tions in the State or under its control (i. e., beyond declared nuclear facilities and LOFs) for any of the following purposes:

1. On a selective basis in order to assure the absence of undeclared nuclear material and activities

2. To resolve a question relating to the correctness and completeness of the information provided pursuant to the AP or to resolve an inconsis­tency relating to that information

3. For the Agency to confirm, for safeguards purposes, the decommis­sioned status of a facility or of a LOF where nuclear material was cus­tomarily used.

Due recognition should be given to the fact that it is a State’s sovereign decision whether to place an AP in force, and as such, there are many important domestic and international considerations a State may have to address before it is willing to accept the relevant AP obligations. To date, over 100 States have an AP in force. These States have elected to do so in order to increase the effectiveness and efficiency of safeguards applied in the State and/or such action represents a continuing contribution to their international and national non-proliferation goals.

By November 2011 there were 433 nuclear power plants in operation world­wide with a total installed generating capacity of 367 gigawatts (GWe). There were 65 plants under construction with a combined capacity of 62.6 GWe. In 2010 the global fleet of nuclear generating stations produced 2630 terawatt-hours (TWh) of electricity or about 13.5% of total supply.

This chapter is the copyright of the International Atomic Energy Agency (IAEA) and is reproduced by the Publisher with the IAEA’s permission. Any further use or reproduction of the chapter, in whole or in part, requires the permission of the IAEA. The chapter has been written by a staff member of the IAEA in his/her personal capacity and not on behalf of the IAEA or the Director General of the IAEA. The views expressed in the chapter are not necessarily those of the IAEA and that the IAEA disclaims all liability in connection with the chapter and any use made thereof.

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The first decade of the twenty-first century was a paradoxical period for nuclear power. Projections of future growth were revised upwards year by year even though global installed nuclear generating capacity did not grow materially and actually declined after 2007 as several plants were retired and no new reactors were connected to the grid in 2008. It was the first year since 1955 without at least one new reactor coming on-line. There were, however, 10 construction starts, the most since 1987. In 2009 installed nuclear capacity dropped yet again, the first two-year drop in nuclear power’s history, with three reactors being retired and only two new ones connected to the grid. But the projections for nuclear power growth by reputable international organizations were again revised upward, by about 8%, even as the world was still dealing with the financial and economic crises that started in late 2008. One reason for the higher projections was that construction starts on new reactors also increased. There were 11 new construction starts (see Fig. 15.1), extending a continuous upward trend that started in 2003. With 16 construction starts, the year 2010 witnessed a con­tinuation of this trend and the 67 plants under construction at the end of 2010 is the highest number since 1987.

Then again, the share of nuclear-generated electricity in global supplies has been slipping throughout the twenty-first century. In 2009 it was just below the 14% mark (down from 16.8% in 2000) and many analysts have interpreted this as a clear sign of a nuclear demise as nuclear capacity growth was routinely outpaced by total capacity growth. Still, in 2010 every

seventh kilowatt-hour (kWh) produced globally is generated by nuclear power.

The short-term reality of declining market shares is in juxtaposition with the interest expressed by more than 60 countries currently without nuclear energy to add the technology to their national energy supply portfolio (IAEA, 2010).

17.2.1 International environmental protection

Ever since the establishment of the United Nations Environment Programme and the formulation of the 1992 Rio Declaration, environmental protection has played an increasingly significant role in international law. Modern international institutions and instruments seek to promote economic devel­opment whilst at the same time preventing States from wilfully exploiting or neglecting their natural environments.

One particular area which has been a major focus of the international community, and indeed which dates back to the early part of the twentieth century, is the environmental and human health risks associated with ionis­ing radiation. The first important international institution in this field was the International Commission on Radiological Protection (ICRP), which was established in 1928 to publish recommendations on the basis of scien­tific research on the risks posed by radiation exposure.

The International Atomic Energy Agency (IAEA) is another important body in this field. As with the ICRP, the IAEA regularly publishes advice and guidance on how national legal systems can best protect individuals and the environment from radiation harm. In 2006, the IAEA published its 2006 Fundamental Safety Principles (IAEA, 2006, SF-1), which is a set of basic principles which should be applied by States to all circumstances which give rise to a radiation risk. The fundamental safety objective is to protect people and the environment from the harmful effects of ionising radiation over the lifetime of a nuclear facility (includes stages/processes such as planning, siting, design, manufacturing, construction, commissioning and operation, as well as decommissioning and closure). This objective should also be applied to the associated activities of transport and manage­ment of radioactive material and waste.

The IAEA has also published a highly influential document, Milestones in the Development of a National Infrastructure for Nuclear Power (IAEA, 2007), which provides detailed general guidance for States on how to develop national nuclear programmes in an environmentally sensitive manner.

The IAEA is in the process of developing further recommendations and guidance which address the environmental impact of facilities and the envi­ronmental consequences of radioactive releases to the natural environment (Radiological Environmental Impact Analysis for Facilities and Activities and Regulatory Control of Radioactive Releases to the Environment from Facilities and Activities). At the time of publication these safety standards were both under development.

The recommendations and publications of the ICRP and the IAEA have undoubtedly had an enormous influence on the development of the inter­national regulation of nuclear facilities; however, like most instruments of international law, they are not directly enforceable in national legal systems

— they are merely published with a view to guiding States on how to best introduce measures to protect individuals and the environment from radia­tion harm. In order for the measures to apply directly in national legal systems, they must be directly transposed into national law by national legislation.

The emergency plan is considered the last barrier available to protect people against the harmful effects of radiation coming from the liberated radionuclides. It demands a substantial national administrative and techni­cal infrastructure which is reflected in the corresponding emergency plan. The site characteristics require that there should be an efficient way of communicating the situation to the affected people. Among the emergency procedures, in order of increasing importance, it will be necessary to remain indoors, ingest potassium iodide to protect the thyroid, and evacuate people to safer places. Among the long-term measures it is necessary to monitor water and food, to confiscate crops and other products and to establish a decontamination programme. Large population densities, intensive indus­trial and agricultural development, complicated topography and lack of evacuation routes are impediments to an efficient emergency plan.

The principle on the ultimate heat sink provisions is defined as given below:

Principle 4: The site selected for a nuclear power plant has a reliable long-term sink that can remove energy generated in the plant after shutdown, both imme­diately after shutdown and over the longer term.

The generation of residual energy after reactor shutdown due to the disin­tegration of the radioactive fission and activation products, the so-called decay heat, is a specific property of nuclear power. The impossibility of removing such energy causes the heating up of the core, the loss of fuel integrity and its potential meltdown and the release of radionuclides. Therefore the availability of an ultimate heat sink is an unavoidable require­ment. This ultimate heat sink could be the same as the sink receiving the heat rejected from the thermodynamic circuit, but under accidental condi­tions the decay heat can be released to the atmosphere providing that such systems will withstand all foreseeable extreme circumstances.

The TR document structure depends on the contract approach selected by the owner:

• Under a complete plant approach on a turnkey basis (NI + TI + BOP), it is sufficient to prepare one TR document, where the requirements can be organised as follows:

— General requirements (applicable to the NI, TI and BOP)

— NI technical requirements

— TI technical requirements

— BOP technical requirements.

• Under a split — or multi-package approach (e. g. NI, TI and BOP sepa­rate), preparing a specific TR document for each large package to be contracted separately (e. g. one for the NI, one for the TI and one for the BOP) results in a more practical and clearer procedure for the bidder. It is also possible to combine packages, for example in the case of BOP being contracted as part of the TI package, in which case a single document is prepared for both. Each of the separate TR documents should be self-standing, containing all the technical requirements appli­cable to the package, without need to refer to another TR document.

In many regulatory organizations the commissioning phase just described is only one part of the operating license. In any case, the licensee has to submit an FSAR, together with a series of additional documents relevant for the operational phase, as described in Table 20.3. The FSAR is a refine­ment of the PSAR, describing the NPP as it has been built and introducing changes in equipment capabilities and operational limits as determined by the results from the pre-nuclear and nuclear tests undertaken. Apart from organizational documents, one of the most significant documents for opera­tion is the Operational Limits and Conditions, also called the Technical Specifications for Operation.

These documents are reviewed by the RB and form the basis of the operating license. By this time, even for new entrant countries, the RB staff will already have accumulated a great deal of experience and expertise; nevertheless, when confronted for the first time with handling the operating license, outside help will be needed. As in previous cases, it is recommended that advice be sought from the RB in the country of origin of the project, from the IAEA, or from TSOs experienced in operating research reactors. In the longer term, the RB will become more independent from external help, except in cases regarding anomalous situations and accidents. In any case, the RB will need to convene a competent body of experts, including those who have been involved in the construction and commissioning phases. Once again, the SER constitutes the basis for the operating license and its limits and conditions.

The operating license covers a great variety of different issues in some detail. Among other things, the license stipulates the procedures according to which an activity is to be carried out, the conditions to be respected, the documentation the operator has to produce, what they have to report to the RB, and whether the participation of a representative of the authority is required.

The license therefore quotes the document on personnel organization which describes the functions, responsibilities and tasks of persons and organizational units. It states the requirements for training for important positions. Operating activities are undertaken according to a number of internal regulations. Those with safety relevance are licensed. Important among these internal regulations are manuals on in-service testing, main­tenance, radiological testing, shift and control room organization, access and security, alarms, physical protection, and quality assurance.

Operation of the plant is guided by procedures for normal operation and for incidents and accidents. Limits and conditions for operation have to be respected. There are also guidelines and procedures for severe accidents, and these documents also form part of the license. There are requirements on the information the authority needs for fuel outages, on the justification of the safety of the new core, and the conditions for restart. The procedure for how plant modifications are to be processed is also fixed at this stage. Additionally, there are requirements on quality assurance for components to be exchanged, with special regard to core internals.

The license stipulates that the operator has to follow and analyze inci­dents in other plants, and justify their conclusions regarding their own plant. It also states how the operator should proceed with reportable events in the plant itself. The license deals with the proof of waste disposal, and the handling of fuel and radioactive waste. Of course, it sets limits for tolerable effluents in air and water. The license is also a basis for the surveillance which the authority will perform during operation. Therefore, it regulates the documentation which the operator has to maintain and the reports they must submit to the authority on a regular basis.

Regular inspections, either announced or not, are conducted by the RB. Some RBs have resident inspectors assigned to each NPP who oversee day-to-day operations and report to the RB headquarters. In case of anom­alous situations, a so-called reactive inspection is put into effect to analyze the situation and oversee the actions taken. Some RBs have established permanent oversight systems, based on selected safety pillars; non­compliance with the defined pillars generates a colour code which measures the importance of the non-compliance, which is maintained until the non­compliance is addressed and corrected.

The nuclear regulatory body needs to be created or expanded, with respon­sibility for defining all safety, safeguards and security requirements accord­ing to codes and standards and ensuring that they are met. The regulator will have a relevant role during the licensing process of a new NPP.

Assistance in developing human resources may be provided by the regu­latory body in the country of origin of the supplier or other regulatory bodies, and complemented by the IAEA and other international organizations.

• Power system planning

• Regulatory framework

• National infrastructure

• Codes and Standards

• Licensing

• Inspection

• Site selection

• Human resources plan

• Bid specification and evaluation

• Training system organization, materials development and delivery of training sessions

• Full-scope simulator

• Conceptual design

• Basic design

• Detailed design

• Equipment and plant specifications and drawing

• Physical protection

• Procurement

Stakeholder Activities Staff Observations Main suppliers and equipment vendors • Equipment and component manufacturing • Equipment erection • Piping supporting and welding • Non-destructive testing 3000 Manufacturing and construction are the activities that have by far the largest manpower requirements, of the order of 6000 people during its peak period Construction companies • Construction, erection and installation of plant buildings • Component and systems erection and installation 2000 1300 Plant operator • Commissioning • Operation and maintenance 40-50 400-1000 Major support during commissioning by the equipment manufacturers Nuclear fuel cycle company and waste management • Exploration • Fuel fabrication • Waste management 100-200 Decommissioning organization • Decontamination • Dismantling • Asset recovery • Waste processing, storage and disposal 500-1000