Problems of Assessing the Health Status of Personnel Working in Conditions of New Technologies for Nuclear Fuel Production

Purpose: To identify the problem of assessing the health status of personnel working under the conditions of new technologies for the production of nuclear fuel. Material and method: The object of the research was the general morbidity of workers in the production of mixed nitride uranium-plutonium fuel (MNUP-fuel). The material for the study was the data presented in the «Health Passports». The paper used the method of comparative analysis of the overall morbidity of workers in the production of MNUP-fuel and workers in enterprises dealing with nuclear fuel. Results and analysis: At present, in our country, within the framework of the «Breakthrough» project, new technologies are being developed for the fabrication and refurbishment of mixed uranium-plutonium (MNUP) fuel. In the absence of radiation and hygienic standards for the content of fuel products in working rooms, in order to assess the influence of production factors, along with the radiation dose, the incidence of personnel is studied as an integral indicator of health. A study of the incidence of 50 workers in the production of MNUP fuel revealed: Relatively high incidence of general morbidity – 1122 diseases per 100 people or an average of 93.5 diseases per 100 people per year, regardless of the length of service. The leading diseases in the overall morbidity structure are diseases of the respiratory system – 26.0 % (1st place), eyes – 13.4 % (2nd place), musculoskeletal system – 11.4 % (3rd place), circulatory system – 10,9 % (4th place), injuries and poisoning – 8.4 % (5th place), digestive organs and genitourinary system – 7.7 % and 7.0 %, respectively (6th place), which make up 84.7 % of the total morbidity. Obviously, the effective dose of 4.6 mSv/year cannot be the only reason for the high morbidity in workers in complex radiochemical production, but characterizes only the influence of one of the many nonspecific factors of production. The existing system for assessing the health of personnel working in radiochemical production, in addition to analyzing the risks of deterministic and stochastic effects, should include an assessment of the overall morbidity of personnel.

Improving Safety of Shielding Chambers Equipped with Viewing Windows

The article describes and proves the possibility of increasing the protection against neutron radiation for personnel by means of immersion liquid without major changes in the design of the equipment used and without reducing the safety of the radiation object. Studies of the components properties of the protection glass and the immersion liquid have shown that the properties of the immersion liquid reduce the dose rate of neutron radiation significantly compared to the protection glass, which is used for the main protection against ionizing radiation when working with uranium-plutonium fuels. The use of two-layer protection in viewing windows allows reducing the dose rate of mixed gamma-neutron radiation to values that do not exceed the safe radiation dose for personnel when working with an ionizing radiation source, which in this case is 50 kg of uranium-plutonium fuel

Enhancing NASA's Multi-Mission Radioisotope Thermoelectric Generator Using Highly Efficient Thermoelectric Materials

This project proposal aims to enhance NASA’s Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) by identifying and analyzing new material technologies that have been researched for their excellent thermoelectric properties at higher temperatures. By choosing the most efficient thermoelectric material available, the MMRTG’s energy conversion efficiency will be greatly improved as thermoelectric generator efficiencies are largely determined by the properties of the materials within the thermocouple devices used to convert the heat into energy. A project that focuses on enhancing the MMRTG is imperative for the future of space exploration as there is global shortage of plutonium fuel production, limiting future missions to available supplies. A more efficient generator will minimize the use of this fuel while maximizing power output, allowing for increased mission capabilities and better conservation of the scarce plutonium fuel. In this report, lanthanum telluride, Yb14MnSb14, and a multiple-filled skutterudite (SKD) compound are analyzed for their excellent thermoelectric performance. The multiple filled SKD compound is chosen as the ideal material to enhance the MMRTG based on the low cost and low risks associated with the material while producing a nearly identical efficiency relative to the other candidates. Keywords: eMMRTG, MMRTG, thermoelectric materials, thermoelectric generator, efficiency