{"id":32232,"date":"2022-05-05T13:21:31","date_gmt":"2022-05-05T13:21:31","guid":{"rendered":"https:\/\/sitepourvtc.com\/?page_id=32232"},"modified":"2023-09-23T06:51:29","modified_gmt":"2023-09-23T06:51:29","slug":"nuclear-safety","status":"publish","type":"page","link":"https:\/\/sitepourvtc.com\/nuclear-power\/reactor-physics\/nuclear-safety\/","title":{"rendered":"Nuclear Safety"},"content":{"rendered":"
Nuclear safety<\/strong>, also known as reactor safety, is defined by IAEA:<\/a><\/p>\n \u2018Safety\u2019 is the achievement of proper operating conditions, prevention of accidents, and mitigation of accident consequences, resulting in protecting workers, the public, and the environment from undue radiation hazards.<\/em><\/p>\n This definition covers more than it may seem. Nuclear safety<\/strong> is a broad engineering concept that ranges from nuclear engineering to the theory of human errors. Nuclear safety is composed of technical and organizational measures taken during all phases of a facility\u2019s life (design, construction, commissioning, operation, decommissioning and dismantling) to protect workers, the general public, and the environment from the effects of radioactive substances.<\/p>\n Most nuclear power plants introduce a \u2018defense-in-depth \u2018<\/b>approach to achieve maximum safety. This approach is constituted of multiple safety systems supplementing the natural features of the reactor core.<\/p>\n According to INSAG-10:<\/p>\n \u201cDefence in depth consists in a hierarchical deployment of different levels of equipment and procedures to maintain the effectiveness of physical barriers placed between radioactive materials and workers, the public or the environment, in normal operation, anticipated operational occurrences, and, for some barriers, in accidents at the plant.\u201d<\/em><\/p>\n Defense in depth ensures that a plant is designed, fabricated, constructed, and operated not only to be safe during normal operation but to account safely for the possibility of a spectrum of accidents. The plant has sophisticated safety systems and devices to guard against human error, equipment failures, and malfunctions taking into account such natural phenomena as earthquakes, tornadoes, and floods.<\/p>\n <\/a><\/p>\n The main reason for this approach lies in the uniqueness of nuclear power plants. Nuclear reactors have three unique characteristics that affect their safety compared to other power plants.<\/p>\n These are the three main characteristics of nuclear reactors and their related safety measures. This covers nuclear power plants and all other nuclear facilities, the transportation of nuclear materials, and the use and storage of nuclear materials for medical, power and industry. However, perfect safety cannot be guaranteed. Potential sources of problems include human errors and external events that have a greater impact than anticipated. It must be added, no industry is immune from accidents, but all industries learn from them. In the chemical and oil-gas industries, major accidents also improve safety. There is a wide public acceptance that the risks associated with these industries are an acceptable trade-off for our dependence on their products and services. In reality, the safety record of nuclear power plants, by comparison with other electricity generation sources, is very good. The use of nuclear energy for electricity generation can be considered extremely safe. Every year several thousand people die in coal mines to provide this widely used fuel for electricity. There are also significant health and environmental effects arising from fossil fuel use.<\/p>\n Three safety functions associated with the three characteristics are a prerequisite to ensuring reactor safety under all circumstances:\u00a0<\/strong><\/p>\n Reactor safety is based on three protective barriers to prevent radioactive releases and the defense-in-depth principle.<\/p>\n Three protective barriers refer to a series of strong and leak-tight physical barriers between radioactive products and the environment. The barriers prevent the release of radioactive products in all circumstances. The goal of defense-in-depth, introduced in the preceding section, is to ensure basic safety functions, i.e., controlling reactivity, cooling irradiated fuel and containing radioactive substances. These safety functions are necessary to ensure all barriers remain effective.<\/span><\/p>\nFive levels of defense<\/h2>\n
Three characteristics that affect nuclear safety<\/h2>\n
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Three fundamental safety functions of nuclear safety<\/h2>\n
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Three protective barriers<\/h2>\n
Classification of Plant States<\/h2>\n