某压水堆核燃料元件生产线辐射水平及对作业人员的健康影响

根据相关的放射卫生国家标准与方法,为保护放射工作人员和公众的健康,对某压水堆核燃料元件生产线工作场所进行了职业危害因素识别,对场所的γ剂量率、主工艺生产岗位α、β表面污染平均水平、α放射性气溶胶浓度进行了监测,对工作人员受照剂量及职业健康体检进行了调查。结果表明,该压水堆核燃料元件生产线属职业病因素危害严重的建设项目,在正常运行时,作业场所的放射性水平符合《电离辐射防护与辐射源安全基本标准》的要求,在正常运行条件下该生产线不会对工作人员的身体造成辐射危害。     

辐射监测及危害评估是核应急医学救援的先导

针对核与辐射突发事件的医学救援工作,出于减少核事故对工作人员和公众的损害,保证救援人员和公众的健康和安全的目的,本文就应急救援中放射源项识别和威胁类型的确定,从辐射监测及危害评估入手,讨论多学科沟通和多单位合作的框架、内容和意义,从而为更加高效、安全地做好核应急救援提供知识和决策基础。     

基于PSA分析事故序列场内工作人员辐射风险研究

从总风险控制的角度,提出了事故工况下场内工作人员剂量与辐射风险接受准则,并建立了相应的评估方法。以典型压水堆核电厂为例,采用概率安全分析（PSA）的全范围事故序列进行验证评价,评估了典型压水堆核电厂事故后场内工作人员的辐射剂量与辐射致死风险。通过验证结果可知,事故后场内工作人员总的辐射致死风险远低于公众由于自然灾害、疾病、交通事故及不同行业的总死亡风险值;事故后工作人员在燃料厂房进行操作时的辐射致死风险占比最高,故工作人员在燃料厂房进行相关操作时,可提前制定相应的辐射防护措施来降低辐射风险;工作群组中其他人员和意外受照人员事故后辐射致死风险占比较高,可通过采用气面罩等方式对气载放射性进行防护以降低其辐射风险。相应的分析结果可为后续核电厂事故后处理方案的制定和事故后场内工作人员辐射防护措施的制定提供借鉴。      

Radiation Accidents: Medical Consequences and Radiation Protection Experience

A generalization of scientific-practical experience with radiation accidents in our country is presented for the example of 175 incidents, three large-scale accidents – Tech River (1949–1952), Mayak combine (1957), the Chernobyl nuclear power plant (1986) – and irradiation of the public as a result of the first nuclear explosion on the Semipalatinsk test area (1949). The medical consequences of these accidents for professional workers and the public are analyzed. It is noted that the most efficient and effective system for organizing medical assistance to the public exposed to accidental irradiation is a differentiated approach to irradiated individuals. The effectiveness of counterradiation protection of people is assessed. Experience gained in this work shows that timely and accurate monitoring of adherence and especially nonadherence to the regulations for accidental and post-accident irradiation of the public and professional workers is one of the most important guarantees for minimizing the consequences of irradiation.     

Radiational impact of mining on the population at large

Conclusions The exploitation of mineral deposits containing natural radionuclides (even in concentrations too small for industrial use) may pose radiation hazards for the nearby population on account of radioactive discharge into the water and the atmosphere and the seeping of radon into living quarters. This risk is especially great if the protective belt around the mine is established incorrectly, settlements are laid out without paying attention to the radioecological conditions, or mine wastes are used without supervision in building houses. The technology and equipment here described permits investigation of the distribution of radioactive discharges at mineral deposits. Experience in monitoring the radiation hazards in the region of the Kovdorsk mining and enrichment combine, the Belaya Zima prospecting region, and elsewhere may be used wherever natural radionuclides are present as primary of secondary components. However, it is necessary to employ high-accuracy methods and equipment permitting the use of milligram samples; in particular, laser-luminescent analysis of uranium in the samples is recommended. It is important to develop and publish standard documents on estimating the radiation hazards of mineral deposits, both for the protection of the population and as a means of preventing irrational fear of radiation, which is often a greater threat to the public health than are natural radionuclides themselves. A. A. Logachev All-Russian Scientific-Research Institute of Exploratory Geophysics. Translated from Atomnaya énergiya, Vol. 84, No. 4, pp. 299–303, April, 1998.     

Radiation consequences of a hypothetical failure of a dam at the coolant reservoir of the chernobyl nuclear power plant

Mathematical simulation is used to estimate the possible radiation consequences of an accidental failure of the protective dam of the coolant reservoir at the Chernobyl nuclear power plant. The dynamics of the emptying of the reservoir and the escape of radionuclides is calculated. The additional contamination of bottom deposits in the Dnepr River, which can be caused by the accidental escape of radioactive substances from the coolant reservoir, is estimated. The additional dose load to the public is estimated taking account of the food chains. A single-step mathematical model, taking account of the contamination of the water and the bottom deposits, is constructed to study the fish food chain. It is established that for an accidental failure of the protective dam of the coolant reservoir of the nuclear power plant the dose to the public will not exceed 2.5·10⁻³ Sv in the first year after the failure. Therefore, the destruction of the protective dam of the coolant reservoir of the Chernobyl nuclear power plant, if it occurs, will not be a radiation accident, 2. figures, 1 table, 9 references. Translated from Atomnaya énergiya, Vol. 88, No. 4, pp. 303–307, April, 2000.     

放射工作人员外周血淋巴细胞染色体畸变分析

为了解不同职业照射类型、年龄、工龄放射工作人员外周血淋巴细胞染色体的畸变情况,采集四川省1 612名放射工作人员(放射组)和248名健康人员(对照组)外周血,用微量全血培养法培养淋巴细胞,MetaSystems系统分析记录染色体畸变,统计分析染色体畸变率。结果表明,放射工作人员染色体总畸变率显著高于对照组;放射工作人员中,核燃料循环组、工业应用组染色体畸变率明显高于医学应用组,40岁以上人员染色体畸变率高于40岁以下,工龄20年以上人员染色体畸变率高于20年以下。结果提示,放射工作人员较健康人群外周血淋巴细胞染色体畸变明显增加,应进一步提高核燃料循环和工业应用人员的职业防护意识,加强个人辐射防护。     

Quantitative criteria for rehabilitation of the territory of shore servicing bases of the naval fleet

A variant of the application of the norms and regulations currently operating in our country which ensure radiation safety for workers, the general public, and the environment is presented to valdiate the criteria for rehabilitation of the territory of the shore servicing bases of the naval fleet. The main normative-legal documentation on the rehabilitation of the radiation dangerous objects is analyzed and the international and domestic experience in performing such work, including radiation accidents, is examined. The quantitative criteria used in practice for the residual radioactive contamination of industrial objects and housing developments and the environment are singled out, and an attempt is made, on the basis of a generalization of the information available, to adapt individual tenets in the interests of rehabilitation of radiation dangerous shore-based objects of the fleet. __________ Translated from Atomnaya énergiya, Vol. 101, No. 1, pp. 35–49, July, 2006.     

Spent fuel transportation risk assessment: routine transportation

Abstract

The RADTRAN model for calculating radiation doses is based on the well understood behaviour of ionising radiation. Absorption of ionising radiation depends on the energy and type of radiation and on the absorbing material. The casks that are used to transport spent nuclear fuel have walls that absorb most of the emitted ionising radiation and thereby shield the public and the workers. For routine transportation, RADTRAN models the cask as a sphere and assumes that the longest dimension of the trailer or railcar carrying the cask is the same as that of the cask. The dose rate in Sv/h at one metre from the cask is modelled as a virtual source at the centre of a sphere whose diameter is the longest dimension of the actual spent fuel cask. People who live along the cask’s route and the people in vehicles that share the route are exposed to external radiation from the cask. The dose to workers and the public from a cask during routine transportation depends on the time that the workers or public are exposed to the cask, the distance from the cask, and the cask’s external radiation. When the vehicle carrying the cask is travelling along the route, the faster the vehicle goes, the less exposure to anyone along the vehicle’s route. Therefore, an individual member of the public receives the largest dose from a moving vehicle when he or she is as close as possible to the vehicle, and the vehicle is travelling as slowly as possible. In the present analysis, these doses are in the range of four to seven nanosieverts. Collective doses along the route depend on the size of the exposed population. In this study, such doses were of the order of 0·1 person-millisieverts. The appropriate comparison between the collective dose from a shipment of spent fuel is not a comparison between the radiation dose from the shipment and zero dose, but between the background radiation dose in the presence and absence of a shipment, e.g. 8·810096 person-Sv if there is a shipment and 8·81000 person-Sv if there is no shipment.     

Activation analysis of the water cooling system of the LIPAc beam dump

LIPAc stands for Linear IFMIF Prototype Accelerator. LIPAc generates a 9 MeV deuteron beam, which is stopped at a beam dump, depositing over 1 MW of thermal power. A water cooling system has been devised for extracting this energy while keeping operational temperatures within range. The existing high neutron fluxes in the beam dump during operation produce activation of both coolant and beam stopper, which also suffers from corrosion into the coolant. The presence of radioisotopes in the cooling water leads to a radiological hazard.Water purification systems are located outside the accelerator vault and accumulate activated products during filtration, requiring a specific radiological shield to comply with target dose rates. Also devices containing large volume of activated cooling water, like N-16 decay pipes, require specific radioprotection analysis and design. This work identifies the most relevant radiation sources due to the activated cooling fluid, which may result in radiation doses to workers, and propose radioprotection measures into the design to mitigate their effect.     

A Screening Model for Calculating the Risks of Transporting High Level Radioactive Waste

Abstract

In transporting high level radioactive waste (including spent nuclear fuel), shippers (and sometimes carriers) need to evaluate the risks of potential radiation exposure to the public and transport workers. A simple model is presented that can be applied to nuclear waste transport risk assessments. The model considers radiation risks arising from incident free exposure, accidental release-caused exposure to on-link population, off-link population, crew, transport workers, etc. Important parameters and factors that affect the radiation dose level are grouped using the physics of the different exposure phenomena. The total radiation risk (in person-rems) is given by a linear combination of the groups of these factors, each representing a different type of exposure. The radiation exposure risk assessment is reduced to the evaluation of a single linear algebraic equation containing five distinct terms and each term containing the groups of parameters and a constant coefficient. The estimation of the values of the constant coefficients was accomplished by selecting a sample of 65 origin-destination (0-D) pairs and simulating the shipment of high level nuclear waste or spent nuclear fuel between each O-D pair, and evaluating the radiation dose risks to each group of population. RADTRAN 4 was used in the detailed assessments. The coefficient values were tested for statistical robustness using a sampling hypothesis and t-statistics. These values are presented. The simplified model presented here represents a viable and economical option as a radiological risk assessment tool, to be used in mode or route options screening.     

一起工业探伤作业引起的辐射事件的处理及经验反馈

介绍了2017年浙江省宁波地区一起工业探伤作业中(⁷⁵Se放射源)射线误照射事件和该事件处理情况。根据调查及保守剂量估算结果,本次事件中现场非探伤作业人员所受误照射剂量估计值约为29.54 μSv,该估算剂量小于1 mSv的公众年有效剂量当量限值,也小于0.25 mSv每年的管理限值,管理部门根据调查和计算结果将本次误照射定性为辐射事件并通过该事件经验反馈提出监管建议。     

8省1系统实施常见职业性放射性疾病诊断标准的调查

为评估常见放射性疾病诊断标准在职业性放射性疾病诊断医师、放射工作人员、放射卫生监督人员中的贯彻落实情况,了解诊断标准技术性内容及实施过程中存在的问题,采用调查问卷方式,抽调四川、江苏、内蒙、山东、河南、天津、安徽、浙江8省(市、自治区)和核工业系统进行调研,调查问卷分为A、B、C卷,分别对应职业性放射性疾病诊断医师、放射工作人员、放射卫生监督人员。调查结果表明:(1)A卷140人次,B卷2 815人次,C卷310人次,标准掌握及知晓率由高到低依次为职业性放射性疾病诊断医师、放射卫生监督人员、放射工作人员;(2)设定五项标准的综合评分满分为100,职业性放射性白内障的诊断、职业性外照射急性放射病诊断、职业性外照射慢性放射病诊断、职业性放射性皮肤损伤诊断和职业性放射性肿瘤判断规范5项标准的满意评分分别为68.8、74.8、73.5、74.1和72.4。调查结果认为,8省1系统实施五项职业性放射性疾病诊断标准情况较好。     

辐射生物学效应基础与医源性辐射防护

减轻公众医源性辐射负担的当务之急是要求医务工作者在了解辐射生物学效应和辐射防护研究的基础上,尽可能优化各种放射诊疗方案,减少不必要的照射。本文介绍近年来辐射生物效应基础研究、辐射危害的流行病学调查、医源性照射等方面的研究进展,供医源性辐射防护领域的研究和应用借鉴。     

医用质子/重离子加速器辐射屏蔽设计概述

近年来我国医用质子/重离子加速器治癌产业开始飞速发展。粒子加速器运行时会产生次级辐射从而危及环境、公众及工作人员的辐射安全,可靠的辐射屏蔽设计是装置运行时辐射安全的必要保障。本文简要分析了医用质子/重离子加速器辐射屏蔽设计的一般考虑因素;介绍了几种常用的屏蔽计算方法并给出了计算实例。本文的研究内容对未来将要建造的医用质子/重离子加速器的辐射屏蔽设计具有一定的参考意义。     

起草《辐射防护规定》中的某些考虑

本文介绍在结合我国具体情况尽量采用ICRP和IAEA等国际权威组织的有关建议及先进国家的标准的原则下,制定我国《辐射防护规定》中考虑和研究的一些问题。其中主要是:辐射防护最优化原则在辐射防护规定中如何具体化;加强和明确对可能造成天然辐射水平增高的实践的限制的必要性;确定公众成员年有效剂量当量限值和婴儿、儿童的ALI的依据;明确和强调流出物监测的意义;对流出物排放的控制,要将过去单纯的浓度控制改变为既控制浓度又控制总量;明确辐射防护评价的基本要求、主要内容和上报评价报告规定的必要性;对辐射工作人员的医学监督必须根据一般职业医学原则进行等。还介绍了与这些问题有关的近期的一些研究进展。     

某核电站放射工作人员外周血淋巴细胞微核检测结果分析

对2021年在本院体检的某核电站858名放射工作人员外周血淋巴细胞微核检测结果进行了分析。结果表明,放射工作人员的微核细胞率为4.57‰,微核率为4.89‰;不同年龄段放射工作人员的微核细胞率、微核率差异显著,且随年龄增长呈递增趋势;女性放射工作人员的微核细胞率、微核率均高于男性,但差异无统计学意义;不同放射工龄人员的...     

Analysis of the radioactive contamination of the environment due to decommissioned objects of the nuclear-powered fleet in northwestern Russia

The risk of radioactive contamination of the environment is assessed using a comprehensive approach and examination of the questions, including analysis of the structure of the objects and the interaction between them, determination of the sources of the real and potential danger, development of scenarios for accidents and assessment of their probability, the radiation consequences of exposure of workers, the general public, and the environment during salvaging of the nuclear-powered fleet in the Russian northwest. A systematization of the risk is made and the distribution according to the degree of danger is determined. __________ Translated from Atomnaya énergiya, Vol. 101, No. 1, pp. 23–34, July, 2006.     

Transport of radioactive material in Bangladesh: a regulatory perspective

Abstract

Radioactive material is transported in Bangladesh in various types of packages and by different modes of transport. The transport of radioactive materials involves a risk both for the workers and members of the public. The safe transport of radioactive material is ensured in Bangladesh by compliance with Nuclear Safety and Radiation Control (NSRC) Act-93 and NSRC Rules-97. The Bangladesh Atomic Energy Commission is the competent authority for the enforcement of the NSRC act and rules. The competent authority has established regulatory control at each stage to ensure radiation safety to transport workers, members of the general public and the environment. An overview is presented of the activities related to the transport of radioactive material in Bangladesh. In particular, the applicable legislation, the scope of authority and the regulatory functions of the competent authority are discussed. The categories of radioactive materials transported and the packaging requirements for the safe transport of these radioactive materials are also described.     

江苏省实施常见职业性放射性疾病诊断标准的调查

采取问卷调查方式,对江苏省内职业性放射性疾病诊断医师、放射工作人员、放射卫生监督人员开展问卷调查,评估5项常见职业性放射性疾病诊断标准在江苏省的实施情况。结果表明:(1)职业性放射性疾病诊断医师对标准的掌握率为61%～89.6%;参加培训率为59.7%～92.2%;标准应用率为62.3%～68.8%,其培训率和应用率显著高于放射卫生监督人员。(2)放射工作人员除《职业性放射性皮肤疾病诊断》的知晓率同放射卫生监督人员有明显差别外,其余标准知晓率两者无统计学差异。(3)放射卫生监督人员标准的培训率为3.2%～48.0%,显著低于职业性放射性疾病诊断医师和放射工作人员,差异有统计学意义。(4)放射工作人员对职业性放射性疾病认知情况的问题回答正确率为34.7%～89.7%,且医疗机构和非医疗机构无明显差别,放射工作人员对申请职业性放射性疾病提交材料的认知情况为73.6%～100%。(5)职业性放射性疾病诊断医师、放射工作人员、放射卫生监督人员对标准中部分条款的认可度尚可。