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The Atomic Energy Regulatory Board (AERB) is the national authority for ensuring that the use of ionizing radiation and nuclear energy does not cause any undue risk to the health of workers, members of the public and to the environment. AERB is responsible for the stipulation and enforcement of rules and regulations pertaining to nuclear and radiological safety. This paper describes the regulatory process followed by AERB for ensuring the safety of nuclear power plants (NPPs) during their construction as well as operation. This regulatory process has been continuously evolving to cater to the new developments in reactor technology. Some of the recent initiatives taken by AERB in this direction are briefly described. Today, AERB faces new challenges like simultaneous review of a large number of new projects of diverse designs, a fast growing nuclear power program and functioning of operating plants in a competitive environment. This paper delineates how AERB is gearing up to meet these challenges in an effective manner. [ABSTRACT FROM AUTHOR]

The paper brings out the advantages of fast breeder reactor and importance of developing closed nuclear fuel cycle for the large scale energy production, which is followed by its salient safety features. Further, the current status and future strategy of the fast reactor programme since the inception through 40 MWt/13 MWe Fast Breeder Test Reactor (FBTR), is highlighted. The challenges and achievements in science and technology of FBRs focusing on safety are described with the particular reference to 500 MWe capacity Prototype Fast Breeder Reactor (PFBR), being commissioned at Kalpakkam. Roadmap with comprehensive R&D for the large scale deployment of Sodium Cooled Fast Reactor (SFRs) and timely introduction of metallic fuel reactors with emphasis on breeding gain and enhanced safety are being brought out in this paper. [ABSTRACT FROM AUTHOR]

Nuclear energy professionals need to understand and address the catastrophe syndrome that of late seems to be increasingly at work in public mind in the context of nuclear energy. Classically the nuclear power reactor design and system evolution has been based on the logic of minimization of risk to an acceptable level and its quantification based on a deterministic approach and backed up by a further assessment based on the probabilistic methodology. However, in spite of minimization of risk, the reasons for anxiety and trauma in public mind that still prevails in the context of severe accidents needs to be understood and addressed. Margins between maximum credible accidents factored in the design and the ultimate load withstanding capacities of relevant systems need to be enhanced and guaranteed with a view to minimize release of radioactivity and avoid serious impact in public domain. A more realistic basis for management of an accident in public domain also needs to be quantified for this purpose. Assurance to public on limiting the consequences to a level that does not lead to a trauma is something that we need to be able to credibly demonstrate and confirm. The findings from Chernobyl reports point to significant psychological effects and related health disorders due to large scale emergency relocation of people that could have been possibly reduced by an order of magnitude without significant additional safety detriment. A combination of probabilistic and deterministic approaches should be evolved further to minimize consequences in public domain through enhancing safety margins and adding greater precision to quantitatively predicting accident progression and its management. The paper presents the case studies of the extreme external event such as tsunami and its impact on the coastal nuclear plants in India, the containment integrity assessment under the extreme internal event of over-pressurization and aircraft impact along with hydrogen deflagration/detonation-induced loadings. These are at the moment extremely burning issues due to the severe accidents of Fukushima, Chernobyl and Three Mile Island reactors. In the present day context identifying the extreme loadings in a separate category and the corresponding margin assessment is necessary in addition to the implementation of the mitigation and upgraded safety measures. Further, the paper attempts to address the question of public trauma in the event of a serious nuclear reactor accident, a need that has been felt in view of the recent Fukushima and earlier Chernobyl accidents and the resulting large scale relocation due to the present deficient policies and the inherent limitations of Linear No Threshold (LNT) principle. [ABSTRACT FROM AUTHOR]

The continuing research and development on nuclear technology by research establishments in the country and maturing of Indian industry have brought the nuclear energy programme in India to a stage where it is poised to take a quantum leap forward. The vision of expansion of nuclear power also requires a well-structured specialized human resource development programme. This paper discusses the requirements of the human resource development programme for nuclear energy, the challenges in the way of its realization, its national and international status and traces the history of nuclear education in the country. It brings out the linkage of human resource development programme with the nuclear energy programme in the country. It also describes the initiatives by the university system in the area of nuclear education and support provided by the Department of Atomic Energy to the university system by way of extra-mural funding and by providing access to research facilities. [ABSTRACT FROM AUTHOR]

Nuclear energy as a sustainable resource in India has been very clearly formulated in the three stage nuclear programme. The role of thorium as a potential fuel in the third stage of this programme has also been elucidated. With this aim there have been pioneering research efforts in all aspects of the thorium fuel cycle. Thorium being fertile and not accompanied by the fissile species requires the use of a fissile topping. There have been several studies in India on the use of thorium in different reactor systems from thermal to intermediate and fast spectrum, molten salt reactors, high temperature reactors, compact nuclear power packs and even Subcritical systems. In this paper, we present some of the research studies on use of thorium in thermal reactor systems. We give an overview of the neutronic properties of thorium and the bred fissile material and then proceed to show the performance potential in different reactor systems. We also present the innovative Indian reactor designs which utilize thorium, namely the Advanced Heavy Water Reactor (AHWR) and the Indian High Temperature Reactors. [ABSTRACT FROM AUTHOR]

This paper presents an overview of state-of-the art developments in electronics for nuclear power programme of India. Indigenous activities in instrumentation and control (I&C) in the areas of detector development, nuclear instrumentation, monitoring and control electronics and special sensors paved the way to self-reliance in nuclear industry. Notable among the recent I&C systems developed for 540 MWe reactors are Liquid Zone Control System (LZCS), flux mapping system and advance reactor regulating system. In a nuclear plant, apart from ensuring functional requirements, design of electronics needs to meet high level of reliability, safety and security standards. Therefore, a lot of importance is attached to activities such as design review, testing, operation, maintenance and qualifications of I&C systems. Induction of computer based I&C systems mandated a rigorous verification process commensurate with the safety class of the system as specified in Atomic Energy Regulatory Board (AERB) safety guides. Software reliability is assured by following strict development life cycle combined with zero-defect policy and is verified through verification and validation (V&V) process. Development of new techniques in data transmissions with optical fibres as transmission medium and wireless networks in control systems is being pursued. With new I&C systems, efforts were made to utilize the same hardware and software platforms for various plant applications, i.e., for standardization. Thrust was given to use Field Programmable Gate Arrays (FPGA) and Application Specific Integrated Circuits (ASIC) in order to improve the reliability of system by reducing component count. It has become imperative to develop modern contemporary solutions like ASICs, HMCs, System on Chip (SOC) and detector mounted electronics and towards that various ASICs and HMCs have been developed in-house to meet the challenges. [ABSTRACT FROM AUTHOR]

Nuclear power is currently the fourth largest source of electricity production in India after thermal, hydro and renewable sources of electricity. Currently, India has 20 nuclear reactors in operation and seven other reactors are under construction. Most of these reactors are indigenously designed and built Heavy Water Reactors. In addition, a 300 MWe Advanced Heavy Water Reactor has already been designed and in the process of deployment in near future for demonstration of power production from Thorium apart from enhanced safety features by passive means. India has ambitious plans to enhance the share of electricity production from nuclear. The recent Fukushima accident has raised concerns of safety of Nuclear Power Plants worldwide. The Fukushima accident was caused by extreme events, i.e., large earthquake followed by gigantic Tsunami which are not expected to hit India’s coast considering the geography of India and historical records. Nevertheless, systematic investigations have been conducted by nuclear scientists in India to evaluate the safety of the current Nuclear Power Plants in case of occurrence of such extreme events in any nuclear site. This paper gives a brief outline of the safety features of Indian Heavy Water Reactors for prevention and mitigation of such extreme events. The probabilistic safety analysis revealed that the risk from Indian Heavy Water Reactors are negligibly small. [ABSTRACT FROM AUTHOR]