Planned Exposure Situations Research Articles

Low doses of ionising radiation: definitions and contexts

The term 'low dose' is applied to different levels of dose depending on the circumstances of exposure, with the potential for confusion unless the reasoning is clear. The United Nations Scientific Committee on the Effects of Ionising Radiation has defined low absorbed doses of ionising radiation as below about 100 mGy, and low dose rates as below 0.1 mGy min-1 (6 mGy h-1). These values relate to the interpretation of scientific evidence from epidemiological and biological studies. The International Commission on Radiological Protection has used similar values of 100 mSv and 5 mSv h-1 and applied this categorisation directly to the specific situation of patients undergoing diagnostic procedures: doses below 100 mSv were referred to as 'low' and doses below 10 mSv as 'very low'. Consideration of other exposure situations suggest that the same terms can be used for exposures received by emergency workers. However, for workers and members of the public in planned exposure situations, it is suggested that the term 'low dose' applies to doses below 10 mSv and 1 mSv, respectively - that is, below the dose limits. In each case, dose is being used as a surrogate for risk - risks at low doses are uncertain and estimates may change, but order of magnitude considerations are sufficient in most cases. Doses of < 100 mSv, < 10 mSv and < 1 mSv correspond to life-time cancer risk estimates of the order of < 10-2, < 10-3 and < 10-4, respectively.&#xD.

Investigation of radiation doses and dose constraint values of nonmedical planned exposure radiation practices in Taiwan

In Taiwan, the Nuclear Safety Commission (NUSC) is the competent authority responsible for ensuring the safety of ionizing radiation operations. In recent years, the NUSC has introduced the concepts of ALARA and dose constraints (as recommended by the International Commission on Radiological Protection), to control the radiation safety of various radiation sources, and to review the protective control measures. Consideration of these concepts can help ensure that industry operators optimize radiation protection in planned exposure situations. This study investigated the occupational exposure of facility operators using nonmedical planned exposure radiation sources in Taiwan. The NUSC provided a sampling roster, and survey respondents were randomly selected. An on-site radiation safety survey was conducted using a calibrated handheld radiation survey meter to measure the doses that radiation workers were exposed to during normal operations. In addition, the dose constraints of multiple radiation practices were evaluated through the statistical analysis of dose data. From 2020 to 2023, on-site radiation dose surveys were conducted on 1614 radiation sources. Additionally, the average occupational exposure doses of workers in relation to multiple nonmedical radiation operations were evaluated, and recommended dose constraints for these operations were proposed.

Occupational radiological risk assessment and quantification of natural radionuclides present in Pakistani coal

ABSTRACT In this study, 47 coal samples from 16 selected coal mines from four provinces of Pakistan (Punjab, Sindh, Balochistan, and Khyber Pakhtunkhwa) were collected and analysed using a HPGe-based gamma spectrometry system. The objective of the study was to assess the occupational radiological risk from coal reserves in Pakistan. The 226Ra concentration values were found to be higher in coal samples collected from two locations in Meting-Jhumpir Coal Fields and one location of Chakwal Coal Field as compared to the recommended value by UNSCEAR (2000). The 232Th concentration values were found to be higher in coal samples collected from two locations in Padhrar Coal Field, one location in Dandot Coal Field and one location in Cherat Coal Field as compared to the recommended value by UNSCEAR (2000). The 40K values in all the analysed samples were found to be well below the recommended value by UNSCEAR (2000). From the radiological parameters, the values of the representative gamma index, which corresponds to an annual effective dose, were found to be higher than 1 Bq-kg−1 among the samples collected from Meting-Jhumpir coal fields, Chakwal coal field, Padhrar coal fields, Dandot coal fields, Hangu coal field, and Cherat coal fields. Excess lifetime cancer risk was estimated to be in the range of 0.07 × 10−3 − 0.34 × 10−3 with an average value of 0.18 × 10−3. The annual effective dose was estimated in the range of 0.01–0.07 µSv- y−1, which is below than the value established by the IAEA as the safe limit for the public in a planned exposure situation (1 mSv-y−1). It can be concluded that for some of the coal fields, the radionuclide concentration values and some of the radiological parameter values were found to be higher than the recommended values. Site-specific studies using direct radiation and radon measurement instruments are proposed for these coal fields to further investigate the radiological situation and its implications on workers and the public’s health. Furthermore, we have used a theoretical approach to estimate the occupational health hazard based on the activity concentration of radionuclides in the coal samples, which needs to be validated with the direct-dose measurement techniques.

Derivation of dose constraint for the general public around nuclear power plants with operational data of radioactive effluent releases

For radiation protection optimization, ICRP proposed dose constraint as quantitative value for planned exposure situation based on representative person concept. The objective of this study is to derive dose constraints for the general public around nuclear power plants in Korea by applying representative person concept. The dose constraints for the general public around NPPs were derived through a total of six steps. The steps consisted of setting source terms, setting exposure pathways and scenarios, setting candidate groups for a critical group decision, setting habit data, calculating radiation doses, and proposing dose constraints. Through these steps, the radiation dose distribution of the general public around the NPPs was obtained, and dose constraints were proposed using the dose distribution. Radiation doses to the general public around all the Korea NPP sites ranged 1.63 × 10−2 to 1.32 × 10−1 mSv/y. Using the dose distribution, 0.15 mSv/y, 0.10 mSv/y, and 0.08 mSv/y were proposed as dose constraints. The dose constraint values derived in this study are proposals. Therefore, it is judged that the dose constraints should need furthermore discussion with regulators, licensees, and radiation protection experts considering societal and economic factors for radiation protection. The proposal for dose constraints developed in this study can be used to optimize radiation protection for the general public around the NPPs.

ОЦЕНКА РАДИАЦИОННЫХ РИСКОВ ЗАБОЛЕВАЕМОСТИ КАТАРАКТОЙ ЛИКВИДАТОРОВ ПОСЛЕДСТВИЙ АВАРИИ НА ЧЕРНОБЫЛЬСКОЙ АЭС С УЧЕТОМ ВЛИЯНИЯ СОПУТСТВУЮЩИХ БОЛЕЗНЕЙ

Purpose: To assess the radiation risk of cataracts among the Chernobyl clean-up workers (liquidators), considering the impact of concomitant diseases on this risk and to determine the dose threshold for the development of cataracts. Material and methods: Radiation risks of cataract incidence were studied in the cohort of liquidators of the consequences of the accident at the Chernobyl nuclear power plant, observed in the system of the National Radiation and Epidemiological Register (NRER) from 1986 to 2021. Among the 62,828 male liquidators, 9,461 new cases of cataracts were detected. The average age of the liquidators at the beginning of exposure was 34 years, the average absorbed dose of external gamma exposure of the whole body was 0.132 Gy, the maximum dose was 1.5 Gy, and the average duration of exposure was 2.5 months. To analyze the relationships of cataract incidence with other diseases and with the dose, a statistical method of link analysis, free from the type of distribution, as well as logistic regression models, were used. Results: The radiation risk of cataracts in the cohort of liquidators who did not have diagnoses of diabetes mellitus, hypoparathyroidism, malnutrition and myotonic disorders depends on the presence of concomitant diseases in the patient: glaucoma (ICD-10 H40–H42), hyperopia (H52.0), myopia (H52.1) or presbyopia (H52.4). For liquidators with comorbidities, radiation risk is statistically significant only 15 years after exposure, with an excess relative risk of ERR/Gy=0.46 with 90 % CI (0.06; 0.90). For liquidators without comorbidities, ERR/Gy decrease over time: from 4.42 with 90 % CI (0.72; 13.41) in the first 5 years, to zero risk 15 years after exposure. Nonparametric estimates of the relative risk (RR) of cataracts for the dose groups of liquidators are consistent with the estimates of ERR/Gy in the linear non-threshold (LNT) model. The determination of the dose threshold for cataracts according to the LNT model, in accordance with the recommendations of the ICRP, leads to estimates from 1.2 Gy to 13.3 Gy, depending on the presence or absence of cataract concomitant diseases in the liquidators. Conclusions: At present, there are no epidemiological evidence for reducing the equivalent dose limit for the lens of the eye for occupational exposure in planned exposure situations at the level of 150 mSv per year, previously established by the recommendations of the ICRP in 2007 and the current Russian radiation safety standards NRB-99/2009.

Operational radiation protection challenges for the LHC experiments.

Radiation protection physicists at CERN are often required to assess residual activation for the Large Hadron Collider (LHC) experiments during stop periods in order to ensure adequate optimization during planned exposure situations and to establish proper procedures for the radiological control of materials. Given the complexity of the facilities and of the high-energy and mixed fields inducing the activation, Monte Carlo transport codes are an essential tool to simulate both prompt and residual radiation. The present work highlights the challenges of assessing residual dose rates for the LHC experiments in shutdown configurations and of establishing residual activation zonings. For the latter, a method based on fluence conversion coefficients was developed and is efficiently employed. The practical example of the assessment of the activation of the 600 tons of austenitic stainless steel in the future Compact Muon Solenoid (CMS) High Granularity Calorimeter will be used to demonstrate how these challenges are dealt with and the capabilities of the method developed.

Application of the ALARA principle for radon at work: feedback from the European ALARA network

The Council Directive 2013/59/Euratom has introduced binding requirements for the management of radon in the workplace in Member States of the European Union. How does it work in practice? In 2021, the European ALARA Network created a working group on ALARA for Radon at Work with the objective of collecting and sharing experiences from the field. A survey was developed to detail each step of the national regulations for the control of radon and to describe case studies showing implementation. This article presents a qualitative analysis of the answers received from seven countries. There are no two similar national regulations and, at each step, different provisions, protocols, techniques etc are applicable or recommended. This diversity contributes to the richness of the results and can inform about interesting and good practices, where ‘good’ is defined by what is appropriate in the nationally and locally prevailing circumstances. All national regulations follow a graded approach, which is a key component for the implementation of the optimisation (ALARA) principle, yet several potential weak points that may be challenging to ALARA have been identified and are discussed, namely the radon risk assessment, the focus on numerical values, uncertainties in the measurement, how to obtain economically efficient remediation, and the interface with other regulations. Strengthening collaboration between risk prevention and radiation protection actors could help to provide and build expertise on radon management in the workplace, especially when exposure is managed as a planned exposure situation.

Assessing the need for radiation protection measures in artisanal and small scale mining of tantalite in Oke-Ogun, Oyo State, Nigeria

There is concern that work scenarios on the tantalite mining sites in Oke-Ogun, Oyo State, Nigeria may cause occupational radiation exposure of workers due to enhanced concentrations of naturally occurring radionuclides in some process materials. A prior radiological assessment of the mining activities was carried out to determine if and which exposure scenarios may require radiation protection measures. Samples of the materials involved, comprising tantalite (tantalum ores), soil and waste rock were collected and analyzed for activity concentrations of 40K, 226Ra, 238U and 232Th using a hyper pure germanium detector gamma-ray spectrometer. Radon concentrations in the mines were also measured using a continuous radon monitor - Radon-Scout Plus (Sarad, GmbH). Activity concentrations of 40K are below 10 Bqg-1 in all the samples but all the tantalite samples contain more than 1 Bqg-1 of 226Ra and 238U. Hence tantalite is regarded as naturally occurring radioactive material (NORM) and the mining activity as a practice. The requirements for planned exposure situations apply to all the mining sites but, on the basis of graded approach, the optimum radiation protection measures vary from one mine to another, ranging from exemption to authorization. Exposures to radon in the underground mines pose the greatest radiological risks and portend the greatest need for regulatory control in the mining operations. The results further underscore the need to integrate radiation protection with the other health and safety measures in the mining sector.

Bounding uncertainties around the conceptual representation of species in radiological assessment in the context of routine atmospheric release

Wildlife protection has become of regulatory interest since the International Commission on Radiological Protection (ICRP) developed an approach to assess the level of radiological protection specifically for animals and plants. For the purpose of demonstrating compliance with regulation to protect the environment against routine authorised discharges from nuclear facilities, the wide variety of biota inhabiting an ecosystem needs to be condensed to a limited set of representative organisms, as proposed by the ICRP with a set of ‘reference animals and plants’ which can be considered representative of many other species. It is now recommended in the International Atomic Energy Agency Safety Standards, and internationally accepted, that the use of such a limited number of organisms to represent a pool of species is adequate for radiation protection purposes, particularly in planned exposure situations. Adding site-specific species to that set of surrogate species can respond to various interests, such as ensuring a site-specific context to the assessment that addresses stakeholder interests and can aid in stakeholder consultation and risk communication. Moreover, there is a need to question whether the use of the set of surrogate organisms is conservative enough to cover a wider range of biodiversity. Previous studies partially answered this question and this paper adds a range of test cases. A selection of hypothetical representations of possible site-specific species are assessed on the basis of possible variations in size (mass) and occupancy habits. Dose rates are evaluated to determine the greatest difference between hypothetical organisms and those for reference organisms (ROs), considering radionuclides (RNs) potentially discharged in atmospheric routine release from different nuclear facilities. Differences observed in the results between hypothetical organisms and ROs were less than one order of magnitude in all cases, the difference being dependent on the RNs considered. These findings do not preclude the inclusion of site-specific species in environmental radiological assessments if it is considered necessary, but they provide reassurance that using ROs for radiological impact assessments in the case of routine atmospheric discharges is sufficient.

Current status of eye-lens dosimetry in Canada

For occupational exposures in planned exposure situations International Commission on Radiological Protection (ICRP) publication 118 recommends an equivalent dose limit for the lens of the eye of 20 mSv yr−1 averaged over five years with no single year exceeding 50 mSv. This constitutes a reduction from the previous limit of 150 mSv yr−1. The Canadian nuclear regulator, the Canadian Nuclear Safety Commission, responded to the ICRP recommendation by initiating amendments to the Radiation Protection Regulations through a discussion paper which was published for comment by interested stakeholders in 2013. The revised equivalent dose limit of 50 mSv in a one-year dosimetry period for nuclear energy workers came into effect in January 2021. This paper presents the outcome of discussions with Canadian stakeholders in diverse fields of radiological work which focused on the implementation of the reduced occupational equivalent dose limit for the lens of the eye in their respective workplaces. These exchanges highlighted the existing practices for monitoring doses to the lens of the eye and identified current technological gaps. The exchanges also identified that, in many cases, the lens of the eye dose is anticipated to be well within the new dose limit despite some of the gaps in technology. The paper also presents the monitoring and eye-lens dose assessment solutions that are available based on different methods for eye-lens monitoring; presented together with criteria for their use.

Protection of the environment

The International Commission on Radiological Protection's (ICRP) system to protect the living components of the environment is designed to provide a broad and practical framework across different exposure situations. The framework recognises the need to be able to demonstrate an adequate level of protection in relation to planned exposure situations, whilst also providing an ability to manage existing and emergency situations in an appropriate way. In all three exposure situations, the release of radionuclides into the natural environment leads to exposures of non-human biota (wildlife), as well as having the potential for exposures of the public. How the key principles of the ICRP system of radiological protection apply in each of these exposure situations will be discussed. Using examples, we will demonstrate how the overall approach provides a mechanism for industry to assess and demonstrate compliance with the environmental protection objectives of relevant (national) legislation, and to meet stakeholder expectations that radiological protection of the environment is taken into consideration in accordance with international best practice. However, several challenges remain, and these will be discussed in the context of the need for additional guidance on the protection of the environment.

Measurements of the doses of eye lens for the workers of Fukushima Daiichi Nuclear Power Plant

In Japan, the possibility to change the current dose limit of the lens of the eye for the radiation workers working in the planned exposure situation (normal controlled situations) to a new ICRP dose limit was discussed. It was further discussed how to appropriately monitor and manage the equivalent dose of the eye lenses for these workers exposed to radiation at their workplaces, such as nuclear and medical facilities. Among the workers exposed to a high-dose radiation at the water storage flange tank deconstructed 90Sr/90Y dominant areas and the nuclear reactor buildings (high dose gamma-ray) of the Fukushima Daiichi Nuclear Power Plant (1F-NPP), Hp(10), Hp(3), and Hp(0.07) at the head and the chest (or the upper arm) were estimated by passive personal dosimeters using thermoluminescence dosimeters (TLDs) and radio photoluminescence glass dosimeters (RPLGDs). The relationship between Hp(10), Hp(3), and Hp(0.07) along with the effects of the sites of wearing dosimeters on the head inside a full-face mask and the chest (or upper arm) were discussed.

An experiential approach to developing radiological content for public health nursing: Lessons from a nuclear disaster.

This study identified the radiological content required for PHNs and public health nursing students based on PHNs' experiences caring for people affected by the 2011 Fukushima Daiichi nuclear power plant accident. We used qualitative research, interviews, and content analysis. Participants were eight PHNs employed by local governments in Fukushima and neighboring prefectures. Six content themes regarding the nuclear disaster were identified: (a) basic knowledge about radiation, (b) public health nursing activities in emergency exposure situations, (c) management in emergency exposure situations, (d) consultation to support residents affected by the nuclear disaster, (e) activities in the existing exposure situations, and (f) disaster preparedness in the planned exposure situations. Necessary content shifted depending on the phase of the nuclear disaster recovery. The use of the experiences of PHNs after the nuclear power plant accident to inform PHNs and public health nursing students will enable PHNs to respond appropriately and support people without difficulties. Comprehensive radiation content is needed to address the range of situations caused by nuclear disaster.

Community‐Oriented Risk Communication in Recovery Efforts after Radiological Contamination/Accidents

The high levels of public worry and distrust of authorities, especially as associated with nuclear energy and radioactive waste, are well established in the literature and in the experience of risk communicators dealing with the general public. Though much of the experience with the heightened sense of worry that accompanies planned exposure situations associated with proposed radioactive/nuclear facilities (e.g., radioactive waste repositories, nuclear power plants, yet to be approved or built), there are also examples of existing exposure situations such as those following radiological accidents (e.g., Chernobyl or Fukushima). Some risk perception factors (e.g., trust, dread) are common to both planned and existing exposure situations, whereas others (e.g., volition, controllability) may be more prevalent in post‐accident exposure situations. Specific risk perceptions held by a given population and its various subgroups must be acknowledged and incorporated into successful risk communication and public engagement strategies. Post‐accident recovery programs and remediation projects, while in many countries requiring stakeholder and public acceptance to proceed, often fail to incorporate the specific risk perceptions held by the various affected groups in their risk communication and public involvement strategies. Such failures can foster a skeptical or angry public reaction, and hamper recovery in terms of both primary measures (radiological risk reduction interventions) and secondary measures (aiming at “return to normal life,” removal of stigmatization, health and well‐being, etc.). Existing exposure situations and the corresponding mitigations are often approached as local or national scale issues, but by their nature of following radiological emergencies or nuclear accidents, issues of multinational risk perceptions may also arise. Confronting risk perceptions featuring high levels of uncertainty, issue complexity, distrust, information asymmetry, and so forth, requires more interactive forms of governance and adaptive approaches to securing public acceptance. A suggestion is made to deploy an iterative continuous improvement model for incorporating specific risk perceptions into risk communication programs in concert with mutual‐gains‐based public engagement mechanisms.

Implementation of the integrated approach in different types of exposure scenarios.

The International Commission on Radiological Protection (ICRP) recognises three types of exposure situations: planned, existing, and emergency. In all three situations, the release of radionuclides into the natural environment leads to exposures of non-human biota, as well as the potential for exposures of the public. This paper describes how the key principles of the ICRP system of radiological protection apply to non-human biota and members of the public in each of these exposure situations. Current work in this area within ICRP Task Group 105 is highlighted. For example, how simplified numeric criteria may be used in planned exposure situations that are protective of both the public and non-human biota. In emergency exposure situations, the initial response will always be focused on human protection; however, understanding the potential impacts of radionuclide releases on non-human biota will likely become important in terms of communication as governments and the public seek to understand the exposures that are occurring. For existing exposure situations, there is a need to better understand the potential impacts of radionuclides on animals and plants, especially when deciding on protective actions. Understanding the comparative impacts from radiological, non-radiological, and physical aspects is often important in managing the remediation of legacy sites. Task Group 105 is making use of case studies of how exposure situations have been managed in the past to provide additional guidance and advice for the protection of non-human biota.

Dose estimation to eye lens of industrial gamma radiography workers using the Monte Carlo method

The ICRP Statement on Tissue Reactions (2011), based on epidemiological evidence, recommended a reduction for the eye lens equivalent dose limit from 150 to 20 mSv per year. This paper presents mainly the dose estimations received by industrial gamma radiography workers, during planned or accidental exposure to the eye lens, Hp(10) and effective dose. A Brazilian Visual Monte Carlo Dose Calculation program was used and two relevant scenarios were considered. For the planned exposure situation, twelve radiographic exposures per day for 250 days per year, which leads to a direct exposure of 10 h per year, were considered. The simulation was carried out using a 192Ir source with 1.0 TBq of activity; a source/operator distance between 5 and 10 m and placed at heights of 0.02 m, 1 m and 2 m, and an exposure time of 12 s. Using a standard height of 1 m, the eye lens doses were estimated as being between 16.3 and 60.3 mGy per year. For the accidental exposure situation, the same radionuclide and activity were used, but in this case the doses were calculated with and without a collimator. The heights above ground considered were 1.0 m, 1.5 m and 2.0 m; the source/operator distance was 40 cm, and the exposure time 74 s. The eye lens doses at 1.5 m were 12.3 and 0.28 mGy without and with a collimator, respectively. The conclusions were that: (1) the estimated doses show that the 20 mSv annual limit for eye lens equivalent dose can directly impact industrial gamma radiography activities, mainly in industries with high number of radiographic exposures per year; (2) the risk of lens opacity has a low probability for a single accident, but depending on the number of accidental exposures and the dose levels found in planned exposures, the threshold dose can easily be exceeded during the professional career of an industrial radiography operator, and; (3) in a first approximation, Hp(10) can be used to estimate the equivalent dose to the eye lens.

Assessment of indoor radon levels in Portuguese thermal spas

The concentration of radon was assessed in the indoor air of 14 thermal spas and in the home of a selected worker from each thermal spa. The measurements of the indoor radon concentration were carried out using CR-39 detectors, placed in both the workplaces and workers’ homes, exposed for an average period of 45 days, in different seasons of the year. For the thermal spas, the indoor radon concentration ranged between 73 and 4335 Bq m -3 , with a geometric mean of 445 Bq m -3 and an arithmetic mean of 687 Bq m -3 , and within the workers’ homes ranged between 68 and 4051 Bq m -3 , with a geometric mean of 410 Bq m -3 and an arithmetic mean of 785 Bq m -3 . The annual effective doses due to radon inhalation were calculated considering two different exposure scenarios for the thermal spas. For the worst-case scenario, assuming that workers do not have job rotation, the values varied between 1 and 31 mSv y -1 , while for an exposure scenario considering job rotation, the calculated dose ranged between 0.6 and 16 mSv y -1 . For workers’ homes, the calculated dose ranged between 2 and 102 mSv y -1 . The results showed that the EU reference level of 300 Bq m -3 (Directive 2013/59/EURATOM) was exceeded in several cases. In 36% of the thermal spas the exposure of the workers is likely to exceed the effective dose of 6 mSv y -1 and in this case, according to the Directive, it should be considered as “a planned exposure situation”.

Contaminated sites from the past: experience of the US Environmental Protection Agency.

The purpose of this paper is to provide an overview of the experience of the US Environmental Protection Agency (EPA) in cleaning up radioactively contaminated sites. In the USA, EPA regulates the radiological clean-up of uranium mill tailings sites, some Department of Energy legacy sites within the US nuclear weapons complex, and Superfund National Priorities List sites. The approach to site remediation decisions, including the determination of clean-up levels, varies according to the enabling legislation granting EPA these authorities. Past practices that gave rise to many of the existing exposure situations at legacy sites were permissible before the advent of environmental clean-up legislation. The Uranium Mill Tailings Radiation Control Act of 1978 authorised EPA to set applicable radioactivity concentration standards for soil clean-up at inactive uranium mill sites and vicinity properties. For the other categories of sites mentioned above, remediation goals are typically based on not exceeding a target excess cancer risk range established under the Comprehensive Environmental Response, Compensation, and Liability Act (also known as 'Superfund'). EPA's regulations for cleaning up various contaminated sites in existing exposure situations often result in residual doses that are typical of optimised doses in planned exposure situations. Although the clean-up levels selected may differ from those adopted in other countries, recommendations from the International Commission on Radiological Protection are reflected in the exposure assessment methodologies used in their establishment.

On problems of the lens of the eye radiation dose monitoring

According to results of in-depth studies, the risk of the radiation-induced cataract is higher than it was considered earlier. In April 2011, ICRP released a statement on the tissue reactions. The statement recommends that for the case of for occupational exposure in planned exposure situations, an equivalent dose for the lens of the eye should be less than 20 mSv in a year, averaged over the defined periods of 5 years, with no single year exceeding the value of 50 mSv. In this regard, the new standard IAEA № GSR Part 3 provides the dose limit of 20 mSv in a year for occupational exposure for the lens of the eye. The dosimetric data on levels of exposure for personnel in the Russian Federation is practically absent. This paper performs a preliminary evaluation of equivalent dose for the lens of the eye for personnel working in X-ray operating rooms of medical facilities in Saint Petersburg and Kazan. This group of personnel was selected because of the fact that methodic of carrying out procedures forces medical staff to be not only in the zone of scattered radiation but also in the X-ray beam. This fact significantly increases exposure doses for the personnel. It is shown that actual annual dose can exceed the new dose limit (the highest recorded value Нр(3) in 3 months of work was 8,6 mSv). We made a conclusion on the necessity of the lens of the eye dose monitoring amongst interventional specialists on conditions that new limits will be established in the Russian Federation. The Russian and foreign dosimeters for measurement of individual dose equivalent for the lens of the eye Нр(3) which have been registered in the Russian State Register of Measuring Instruments, are descrivebed in the paper.

A universal radiation protection system based on individual standardised integrated doses.

A 'Universal Radiation Protection System' (URPS) is proposed in this paper with a novel philosophy, concept and methodology. It applies a 'Standardised Integrated Dose System' (SIDS) based on health risk limits for workers and public, no matter where they live in the world. The URPS assigns equal radiation health risk limit to an individual by integrating doses from national natural background (NBG) radiation and from man-made sources. For public, the SIDS integrates doses from planned exposure situations within a dose limit (e.g. 1 mSv y(-1)) on top of the mean national NBG dose in a country. For workers, the SIDS integrates within a dose limit (e.g. 20 mSv y(-1)) of occupational dose and doses from mean national NBG and from planned exposure situations as a member of public within the public dose limit. A panorama overview and the rationale in support of the URPS are presented and discussed with a hope to ignite further thoughts and ideas towards establishing the URPS for universal use.