The article analyzes 20-year experience in radiation-hygienic certification in the Russian Federation and the Unified System of Individual Dose Control of the citizens. Radiation-hygienic passport is an objective and accessible information about the characteristics of all sources of ionizing radiation (man-made, medical, natural) and the radiation doses of the population caused by them on the territory of the whole country and in particular subjects of the Russian Federation. Radiation-hygienic passportization and the Unified System of Individual Dose Control of the citizens are currently covering all enterprises that carry out handling with technogenic sources of radiation, supervised by the Rospotrebnadzor and the Federal Medical and Biological Agency of the Russian Federation, and subordinated to the Ministry of Internal Affairs, the Ministry of Defence, the Federal Security Service, the Federal Service for the Execution of Punishments and the Presidential Executive Office. The Interregional Radiation Safety Centers play an important role in improving the effectiveness of organizational work, filling the passports with objective information. The Centers were created by the order of the Rospotrebnadzor in 2007, capable of performing all types of radiation control necessary for the qualitative filling of radiation and hygienic passports, including for the attached territories. The work on the certification of radiation facilities and territories has made it possible to establish the levels and exposure structure of the country’s population from all major sources of ionizing radiation and to identify population groups for which doses due to the natural sources exceed 5 and 10 mSv/year; control and accounting of radiation doses to patients have been introduced in the practice of medical institutions. The work is underway to optimize the structure of medical radiology research; the system of establishing reference levels of medical exposure has been introduced. In order to improve the radiation-hygienic passports of the territories, it is necessary to obtain information on radioactive contamination of environmental media by all constituent entities of the Russian Federation, and timely improve the methodological documents and software to fill them.

This article presents a description of the sources of ionizing radiation and annual doses to the population as a whole for the Russian Federation and separately for the subjects, as well as for the most exposed population groups. The average individual effective annual dose of Group A personnel in 2016 was 1.2 mSv, or 6.0% of the average annual dose limit of 20 mSv. During the period from 1998 to 2005, the average annual individual doses of the personnel of Group A gradually decreased from 2.9 mSv to 1.4 mSv and then stabilized at a level of 1.2–1.4 mSv. The average per inhabitant of the Russian Federation annual effective dose due to natural sources, according to data for 1998-2016, is 3.33 mSv/year, for the Altai Republic – 8.97 mSv/ year, and for some of the most exposed population groups – 3-60 and more mSv/year. Radon exposure makes up the largest fraction (59.50%) of radiation dose due to natural sources. The average per inhabitant of the Russian Federation annual effective dose due to medical exposure in 2016 was 0.51 mSv/year, and after some stabilization in 2013-2015 at a level of 0.45-0.48 mSv/year, there was a tendency to increase. The average annual effective dose of the Russian Federation citizens from all sources of ionizing radiation is 3.76 mSv/year. The highest value of this quantity in 2016 took place in the Republics of Altai (7.2 mSv), Tyva (5.7 mSv), Adygea (5.6 mSv), the Irkutsk region (5.7 mSv) and in the Jewish Autonomous Oblast (6.6 mSv). Natural sources of radiation in the Russian Federation determine 86.1% of the collective radiation dose of the population, medical exposure – 13.6%. In general, the radiation situation in the Russian Federation remains stable over the last decades and in the prevailing territory can be characterized as satisfactory, with the exception of territories affected as a result of the past radiation accidents (Chelyabinsk region, southwestern districts of the Bryansk region) and some settlements in those subjects of the Russian Federation, where exposure of significant populations due to natural sources of ionizing radiation exceeds 10 mSv / year. 

In 2016, St. Petersburg Research Institute of Radiation Hygiene named after Professor P.V. Ramzaev developed a Program for the radiation risk communication management for the adequate perception risks associated with the use of various technologies in the nuclear industry by the public. Carrying out sociological research is one of the stages of this program. The aim of the analysis presented in the article is to study the population’s awareness of radiation safety issues and its attitude to further development of the nuclear industry. The data used in this analysis is a part of a large sociological survey conducted in St. Petersburg and the Leningrad Region The sociological research was conducted by the method of a selective questionnaire survey among the adult population permanently residing in the territory of St. Petersburg and the Leningrad Region. The volume of the sample studied was 2369 respondents: 1006 in St. Petersburg and 1363 in the Leningrad Region, including Sosnovy Bor – 401. The analysis showed that the population of all the studied territories estimates the environmental situation as being mainly favorable. The residents consider the main environmental problems in all areas studied to be a collection, removal, storage, disposal of garbage, as well as air and water pollution. The population of the region is relatively poorly informed about the current projects in the nuclear industry. One-third of the inhabitants of the region perceives the Leningrad nuclear power plant as a source of danger. Respondents see the main danger in the possibility of an accident on it. There is a sharply negative attitude of the population towards the construction of radioactive waste disposal sites anywhere in the region. According to the results of the study, it can be concluded that the population of the studied region is poorly informed about the existing radiation situation and the nuclear industry projects. It requires an optimization of the choice of methods for risk communication. 

The study is devoted to a mass reflection of the problems of radiation safety and the functioning of the nuclear industry in the modern Russia. The analysis of the population’s awareness, peculiarities of the perception of radiation risks and the tendencies in the formation of a public assessment of large nuclear projects have been carried out. Materials and Methods: The data were collected during mass surveys of representative samples of the population of two regions located in the Northwest of the Russian Federation: 1) St. Petersburg and the Leningrad region. (2369 respondents, November 2016) and 2) the Murmansk region. (802 respondents May 2017). The results show that radiation is perceived by society as one of the most significant threats to life and health. However, the public concern does not give rise to a mass interest in the thematic information. The real level of knowledge of the population is clearly insufficient for literate actions in an extreme situation, or for the safe behavior in the everyday life. Public opinion is formed mainly on the basis of mass media reports. At the same time, it has been established that groups of the population well informed in the radiation field are much more likely, than others, to support the nuclear industry, including the least popular projects. Conclusion: Therefore, active informing of the population on the issues of the operation of nuclear facilities, the presence of radioactive contamination sites and other sources of danger, etc. objectively contribute to the growth of the industry’s reputation. It is advisable to use social technologies to overcome the cognitive and practical passivity of the Russian citizens and to form the population’s radiation culture. 

This paper focuses on occupational and public exposure during operation of disposal facilities receiving liquid and solid radioactive waste of various classes and provides a comparative analysis of the relevant doses: actual and calculated at the design stage. Occupational and public exposure study presented in this paper covers normal operations of a radioactive waste disposal facility receiving waste. Results: Analysis of individual and collective occupational doses was performed based on data collected during operation of near-surface disposal facilities for short-lived intermediate-, lowand very low-level waste in France, as well as nearsurface disposal facilities for long-lived waste in Russia. Further analysis of occupational and public doses calculated at the design stage was completed covering a near-surface disposal facility in Belgium and deep disposal facilities in the United Kingdom and the Nizhne-Kansk rock massive (Russia). The results show that engineering and technical solutions enable almost complete elimination of internal occupational exposure, whereas external exposure doses would fall within the range of values typical for a basic nuclear facility. Conclusion: radioactive waste disposal facilities being developed, constructed and operated meet the safety requirements effective in the Russian Federation and consistent with relevant international recommendations. It has been found that individual occupational exposure doses commensurate with those received by personnel of similar facilities abroad. Furthermore, according to the forecasts, mean individual doses for personnel during radioactive waste disposal would be an order of magnitude lower than the dose limit of 20 mSv/year. As for the public exposure, during normal operation, potential impact is virtually impossible by delaminating boundaries of a nuclear facility sanitary protection zone inside which the disposal facility is located and can be solely attributed to the use of public roads during radioactive waste transportation to the disposal facility site. 

Diagnostic reference levels are the main and the most effective tools of optimization of the radiation protection of patients from medical exposure. Diagnostic reference levels should be established based on the results of dedicated dose surveys, allowing evaluating typical patient dose distributions in a selected dose quantity for the selected X-ray examinations. The aim of the current study was to assess the distributions of typical effective doses in representative Russian regions. Materials and methods: Typical patient effective doses for the 13 most common radiographic X-ray examinations were collected in 203 X-ray rooms in 101 hospitals in six regions of Russian Federation in 2009–2014. A differentiated approach was used for the estimation of the typical effective doses depending on the image acquisition technology. Effective doses were estimated using «EDEREX» (Russia) computational software. Results and discussion: Results of the dose data analysis indicate the lack of significant differences between the distributions of the typical effective doses between the selected regions, allowing merging the regional samples and further evaluating the pooled (joint) sample. A significant ratio of maximum to minimum (up to two orders of magnitude) due to a presence of X-ray units with abnormally high and low typical effective doses was observed for all 13 selected X-ray examinations. Abnormally high typical effective doses can be explained by performing the examinations using high values of tube current-time product (150–600 mAs) on a maximum field size (up 40×40 cm). Removal of the typical effective doses below 5%-percentile and above 95%-percentile of typical effective dose distributions for all examinations would result in a reduction of a mean effective dose by up to 30% and reduction of a 75%-percentile of the distributions by up to 15%. No significant differences between the distributions of TED for analogue and digital X-ray units were observed for the pooled sample for selected examinations except for the examination of the chest in posterior-anterior projection. Conclusions: These results should be considered in the process of establishing and implementing DRLs as well as in the cost-benefit analysis of the optimization in radiography. 

Objectives: Studying the influence of the method of selecting a control group in the radon case-control study on assessment of dose-effect dependence. Study the effect of additional additive or multiplicative risk factors on the results of the study. Materials and Methods: Simulation of a large-scale radon epidemiological case-control study. Analyzing of the influence of the representative value of the comparison subgroup on the results of calculating the odds ratio of the incidence of radiation-induced lung cancer. Analysis of different variants of standardization of the control group on the correctness of the dose-effect dependence. Development of methods for identifying risk factors that affect the incidence of lung cancer and determining the mechanism of their influence (additive or multiplicative). Results: It is shown that the insufficient representativeness of the comparison subgroup used in calculating the odds ratio can significantly distort the estimates of dose-effect dependence. In the presence of factors (sex, smoking, etc.), correlating both with the incidence of lung cancer and of radon concentration, complete standardization of such factors is necessary. Multiplicative risk factors without such correlation do not require additional standardization in the selection of a control group. Calculation of the odds ratio for various risk factors in subgroups differing in the levels of spontaneous cancer incidence allows to determine the significance of this factor for the incidence of lung cancer, and to establish the preferential mechanism of the influence of this factor (multiplicative or additive). Conclusions. When carrying out the radon case-control study, it is necessary to identify risk factors that correlate both with the incidence of lung cancer, and with the radon concentration, to assess the mechanism of action of these factors and to made the complete standardization of the control group for them.

The article is concerned with the scientific justification of approaches to the organization of the final radiation survey of facilities having radioactive contamination, after their rehabilitation. Scientific publications on the previous experience in rehabilitation of facilities contaminated with radionuclides, the organization and conducting a radiation survey before the start of the decontamination, during its implementation and after its completion were analyzed. The experience in the rehabilitation of the site for the temporary storage of spent fuel and radioactive waste in Andreeva Bay in the North-West region of Russia, the locations of peaceful nuclear explosions, experimental nuclear power plants, a radiochemical laboratory, and metallurgical plants, that do not belong to radiation facilities, has been studied. It has been established that, besides the surface contamination of the soil, areas of radioactive contamination on sites of decommissioned radiation facilities with significant depth up to 15 m along the profile are available. These local zones with depth soil contamination are persistent contaminants of the groundwater. The experience in the radiation survey of the peaceful nuclear explosions sites shows the removal of radionuclides from cavities, formed with the use of nuclear explosive technologies for peaceful purposes, on the earth’s surface. An optimized list of radionuclides to be monitored during the radiological survey of rehabilitated facilities was proposed based on the analysis of the composition of radionuclides detected at radiation sites subjected to decontamination. The optimized list includes 14 radionuclides with the half-lives of more than three years. 

The accident at the Chernobyl nuclear power plant was the largest nuclear accident in the world. It led to radioactive contamination of 14 regions of the Russian Federation. In 1991, 4540 settlements were attributable to areas with levels of soil contamination by ¹³⁷Cs of more than 1.0 Ci/km2. As of 2016, 3855 settlements with the population of more than 1,5 million people are carried to a zone of radioactive contamination according to the Government Directive No 1074 dated October 8, 2015 «On Approval of the List of settlements located within the boundaries of the zones of radioactive contamination from the Chernobyl disaster». In accordance with this Directive, in the Leningrad region 29 settlements were classified as zones of radioactive contamination. This article describes the dynamics of changes in the radiation situation and its current state in the territories of the Leningrad Region affected by the Chernobyl accident. The paper presents the dynamics of ¹³⁷Cs and ⁹⁰Sr contents in food products of local origin, the results of calculations of the current average annual effective doses used for the purposes of settlements’ zoning, and the average annual effective radiation doses actually received by the population, dating back to 1986. According to the results of laboratory studies, since 1987, there have been no exceedances of the permissible levels for ¹³⁷Cs s in agricultural products and food raw materials of local origin. However in the wild products (mushrooms) excesses of the permissible levels for ¹³⁷Cs have been periodically detected. The cases of exceeding the permissible levels for the content of strontium-90 in food, drinking water and water from open water bodies were not recorded for the entire observation period; the determined activity was at the level of tens and hundreds of times less than the permissible levels. In 2016, conservatively estimated average annual effective doses of exposure used for the purposes of settlements’ zoning, of residents of settlements in the Leningrad region, referred to the zones of radioactive contamination, do not exceed 0.090 mSv / year. The average annual dose actually received by the population in 2016, does not exceed 0.082 mSv / year. Thus, based on the results of the radiation monitoring, the situation associated with the impact of ionizing radiation sources in the Leningrad Region, formed as a result of the Chernobyl accident, currently is characterized as safe.