19. Fuel assembly (тепловыделяющая сборка)

A set of fuel elements and associated components which are loaded into and subsequently removed from a reactor core as a single unit.

---The number of fuel rods used to make each fuel assembly depends on the type of reactor. A PWR (pressurised water reactor) may use between 121-193 fuel assemblies, each consisting of between 179-264 fuel rods. A BWR (boiling water reactor) has between 91-96 fuel rods per assembly, with between 350-800 fuel assemblies per reactor [21].

--- AREVA supplies fuel assemblies for pressurized and boiling water reactors [28].

---International fuel assembly design team works intensively on the development of new fuel assemblies for pressurized water reactors and boiling water reactors [28].

20. Fuelelement(тепловыделяющий элемент, твэл, топливный элемент)

A rod of nuclear fuel, its cladding and any associated components necessary to form a structural entity. Commonly referred to as fuel rod in light water reactors.

---Arrangement of a number of fuel rods into which the nuclear fuel is inserted in the reactor. A fuel element of a pressurized water reactor contains about 530 kg, that of a boiling water reactor about 190 kg of uranium [28].

--- Extensive research and development leads to robust and reliable fuel element design [28].

--- Much of what is known about uranium carbide is in the form of pin-type fuel elements for liquid metal fast reactors during their intense study during the 1960s and 1970s [37].

21. Sabotage(диверсия)

Any deliberate act directed against a nuclear facility or nuclear material in use, storage or transport which could directly or indirectly endanger the health and safety of personnel, the public or the environment by exposure to radiation or release of radioactive substances [11].

---In any terrorist attack or act of sabotage, the overarching concern is to achieve and maintain a safe shutdown condition, including continued availability of heat sinks and containment of radioactive material until the incident has been brought under control [29].

---In the case of sabotage, the criteria are related to the safety of plant personnel and the public, and the risk acceptance criteria are described in terms of radiological consequences [29].

--- The DBT describes the “attributes and characteristics of potential insider and/or external adversaries, who might attempt unauthorized removal of nuclear material or sabotage, against which a physical protection system is designed and evaluated” [29].

22. Regulatory body(регулирующий орган)

An authority or a system of authorities designated by the government of a State as having legal authority for conducting the regulatory process, including issuing authorizations, and thereby regulating nuclear, radiation, radioactive waste and transport safety.

---For each Contracting Party any regulatory body or bodies given the legal authority by that Contracting Party to grant licenses and to regulate the siting, design, construction, commissioning, operation or decommissioning of nuclear installations [12].

---Regulatory body or bodies given the legal authority by the Contracting Party to regulate any aspect of the safety of spent fuel or radioactive waste management including the granting of licenses [13].

--- The Czech State Office for Nuclear Safety is a regulatory body responsible for governmental administration and supervision in the fields of uses of nuclear energy and radiation and of radiation protection [46].