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1.
提出了一个包括源项、照射途径、核素来源、剂量估算以及与释放限值比较等在内的非人类物种辐射剂量的评估框架;并选择大亚湾核电站所在的自然生态系统为研究对象,以对虾、黑鲷、毛蚶和小球藻4种水生生物为代表,建立它们的剂量学模型,并使用DOE GRADED和EU ERICA的非人类物种剂量计算软件以及Monte-Carlo方法对其剂量进行计算,对大亚湾的辐射环境提供评估参考。  相似文献   

2.
制定我国新辐射防护规定中值得研究的几个问题   总被引:9,自引:1,他引:8  
潘自强 《辐射防护》1998,18(4):269-279
本文描述了制定新辐射防护规定时值得研究的几个问题。1.明确规定人为活动引起的天然辐射照射的控制要求,包括地下矿山和矿物提取工业的职业照射,喷气飞机机组人员的职业照射,以及居室中氡的照射。2.明确和加强当前辐射防护工作需要解决问题的内容,包括流出物的控制,下水道中放射性物质的控制和监测。讨论了应用BSS豁免标准时的某些问题。3.吸取国际辐射防护的新经验,其中特别是ICRP的推荐书和IAEA的标准和导  相似文献   

3.
This report responds to a widely perceived need for professional advice on radiological protection measures to be undertaken in the event of a radiological attack. The report, which is mainly concerned with possible attacks involving 'radioactive dispersion devices', re-affirms the applicability of existing ICRP recommendations to such situations, should they ever occur. Many aspects of the emergency scenarios expected to arise in the event of a radiological attack may be similar to those that experience has shown can arise from radiological accidents, but there may also be important differences. For instance, a radiological attack would probably be targeted at a public area, possibly in an urban environment, where the presence of radiation is not anticipated and the dispersion conditions commonly assumed for a nuclear or radiological emergency, such as at a nuclear installation, may not be applicable. First responders to a radiological attack and other rescuers need to be adequately trained and to have the proper equipment for identifying radiation and radioactive contamination, and specialists in radiological protection must be available to provide advice. It may be prudent to assume that radiological, chemical, and/or biological agents are involved in an attack until it is proven otherwise. This calls for an 'all-hazard' approach to the response. In the aftermath of an attack, the main aim of radiological protection must be to prevent the occurrence of acute health effects attributable to radiation exposure (termed 'deterministic' effects) and to restrict the likelihood of late health effects (termed 'stochastic' effects) such as cancers and some hereditable diseases. A supplementary aim is to minimise environmental contamination from radioactive residues and the subsequent general disruption of daily life. The report notes that action taken to avert exposures is a much more effective protective measure than protective measure the provision of medical treatment after exposure has occurred. Responders involved in recovery, remediation and eventual restoration should be subject to the usual international standards for occupational radiological protection, which are based on ICRP recommendations, including the relevant requirements for occupational dose limitation established in such standards. These restrictions may be relaxed for informed volunteers undertaking urgent rescue operations, and they are not applicable for voluntary life-saving actions. However, specific protection measures are recommended for female workers who may be pregnant or nursing an infant. The immediate countermeasures to protect the public in the rescue phase are primarily caring for people with traumatic injuries and controlling access. Subsequent actions include respiratory protection, personal decontamination, sheltering, iodine prophylaxis (if radio-iodines are involved), and temporary evacuation. In the recovery phase, the relocation and resettlement of people may be needed in extreme cases. This phase may require remedial action, including cleanup, management of the resulting radioactive waste, management of any human remains containing significant amounts of radioactive substances, and dealing with remaining radioactive residues. The guidance given in relation to public protection is based solely on radiological protection considerations and should be seen as a decision-aiding tool to prepare for the aftermath of a radiological attack. It is expected to serve as input to a final decision-making process that may include other societal concerns, consideration of lessons learned in the past (especially these involving the public perception of the risks posed by radioactive contamination) and the participation of interested parties. A radiological attack could also be the cause of radioactive contamination of water, food, and other widely consumed commodities. This possible outcome is considered unlikely to lead to significant internal contamination of a large number of people owing to the large amounts of radioactive material that would be required to cause high levels of contamination of water, food, and other commodities. Nonetheless, the report recommends radiological criteria for restricting the use of commodities under such circumstances. The report concludes by re-iterating that the response to radiological attacks should be planned beforehand following the customary processes for optimisation of radiological protection recommended by ICRP, and that optimised measures should be prepared in advance. Such plans should result in a systematic approach that can be modified if necessary to take into account the prevailing conditions and to invoke actions as warranted by the circumstances. Many potential scenarios clearly cannot induce immediate severe radiation injuries. Therefore, in order to prevent over-reaction, response measures prepared in advance should reflect the real expected gravity of the various possible scenarios.  相似文献   

4.
国际放射防护委员会(ICRP)提出了“防护量”这一概念。最常用的防护量,即有效剂量E,用于设定照射限值,并在实用辐射防护中使用,以实现最优化原则。然而,有效剂量不是一个可测量的量,基于此国际辐射单位与测量委员会(ICRU)为外照射的剂量测定提出了一个可测量的量,即实用量,用于估计有效剂量。目前使用的实用量定义于20世纪80年代,当时核工业是职业辐射防护的主要关注点。当前,在其他辐射领域,特别是高能辐射,实用量的不足之处变得很明显:可能高估或低估有效剂量。因此,ICRU和ICRP在全面研究的基础上,为外照射的剂量测定提出了新的实用量,以克服上述缺点。实用量的新定义与防护量(包括有效剂量)的定义更具相关性,特别是使用了相同的仿真体模。当前提出的实用量通过缩小防护量与实用量之间的定义差异简化了辐射防护量体系,并从整体上改进了对有效剂量的估计。本文讨论了提出的新实用量对实际剂量测定的影响。  相似文献   

5.
《Annals of the ICRP》2007,37(2-4):1-332
These revised Recommendations for a System of Radiological Protection formally replace the Commission's previous, 1990, Recommendations; and update, consolidate, and develop the additional guidance on the control of exposure from radiation sources issued since 1990. Thus, the present Recommendations update the radiation and tissue weighting factors in the quantities equivalent and effective dose and update the radiation detriment, based on the latest available scientific information of the biology and physics of radiation exposure. They maintain the Commission's three fundamental principles of radiological protection, namely justification, optimisation, and the application of dose limits, clarifying how they apply to radiation sources delivering exposure and to individuals receiving exposure. The Recommendations evolve from the previous process-based protection approach using practices and interventions by moving to an approach based on the exposure situation. They recognise planned, emergency, and existing exposure situations, and apply the fundamental principles of justification and optimisation of protection to all of these situations. They maintain the Commission's current individual dose limits for effective dose and equivalent dose from all regulated sources in planned exposure situations. They reinforce the principle of optimisation of protection, which should be applicable in a similar way to all exposure situations, subject to the following restrictions on individual doses and risks; dose and risk constraints for planned exposure situations, and reference levels for emergency and existing exposure situations. The Recommendations also include an approach for developing a framework to demonstrate radiological protection of the environment.  相似文献   

6.
The effect of ionising radiation is influenced by the dose, the dose rate, and the quality of the radiation. Before 1990, dose-equivalent quantities were defined in terms of a quality factor, Q(L), that was applied to the absorbed dose at a point in order to take into account the differences in the effects of different types of radiation. In its 1990 recommendations, the ICRP introduced a modified concept. For radiological protection purposes, the absorbed dose is averaged over an organ or tissue, T, and this absorbed dose average is weighted for the radiation quality in terms of the radiation weighting factor, w(R), for the type and energy of radiation incident on the body. The resulting weighted dose is designated as the organ- or tissue-equivalent dose, H(T). The sum of the organ-equivalent doses weighted by the ICRP organ-weighting factors, w(T), is termed the effective dose, E. Measurements can be performed in terms of the operational quantities, ambient dose equivalent, and personal dose equivalent. These quantities continue to be defined in terms of the absorbed dose at the reference point weighted by Q(L). The values for w(R) and Q(L) in the 1990 recommendations were based on a review of the biological and other information available, but the underlying relative biological effectiveness (RBE) values and the choice of w(R) values were not elaborated in detail. Since 1990, there have been substantial developments in biological and dosimetric knowledge that justify a re-appraisal of w(R) values and how they may be derived. This re-appraisal is the principal objective of the present report. The report discusses in some detail the values of RBE with regard to stochastic effects, which are central to the selection of w(R) and Q(L). Those factors and the dose-equivalent quantities are restricted to the dose range of interest to radiation protection, i.e. to the general magnitude of the dose limits. In special circumstances where one deals with higher doses that can cause deterministic effects, the relevant RBE values are applied to obtain a weighted dose. The question of RBE values for deterministic effects and how they should be used is also treated in the report, but it is an issue that will demand further investigations. This report is one of a set of documents being developed by ICRP Committees in order to advise the ICRP on the formulation of its next Recommendations for Radiological Protection. Thus, while the report suggests some future modifications, the w(R) values given in the 1990 recommendations are still valid at this time. The report provides a scientific background and suggests how the ICRP might proceed with the derivation of w(R) values ahead of its forthcoming recommendations.  相似文献   

7.
自2007年国际放射防护委员会(ICRP)发布一般性建议以来,在解决将这些建议付诸实践所面临的挑战方面取得了一些进展。值得注意的是,为放射防护管理而提出三类照射情况后(即,计划照射、现存照射及应急照射),我们进一步研究了它们在几个领域的应用,如涉及天然放射性物质的工业领域以及核事故发生后的应急与恢复领域。本文着重介绍了最近一些出版物提出的以及持续开展的工作中所涉及的主要问题,重点围绕与放射防护体系伦理基础有关的研究进展、放射防护体系在管理现存照射情况中的应用以及环境放射防护与ICRP防护体系的融合。最后,本文介绍了2022年ICRP成立的与放射防护体系应用相关的新工作组的工作目标。  相似文献   

8.
介绍了非人类物种辐射影响评价方法中参考生物的选择目的、准则等,选取了符合我国西南地区某核场址环境生态系统特征的多种陆生参考生物.参考动物包括鼠、鸟、蜜蜂,参考植物选取梧桐、柳杉、夹竹桃、荆条、野艾蒿,给出了上述各参考生物的生物学性状,为进一步评估其辐射剂量提供了重要的基础数据,最后给出此方面工作的建议.  相似文献   

9.
《Annals of the ICRP》1999,29(1-2):1-109
This report provides guidance on the application of the ICRP system of radiological protection to prolonged exposure situations affecting members of the public. It addresses the general application of the Commission's system to the control of prolonged exposures resulting from practices and to the undertaking of interventions in prolonged exposure situations. Additionally, it provides recommendations on generic reference levels for such interventions. The report also considers some specific situations and discusses a number of issues that have been of concern, namely: natural radiation sources that may give rise to high doses; the restoration and rehabilitation of sites where human activities involving radioactive substances have been carried out; the return to 'normality' following an accident that has released radioactive substances to the environment; and the global marketing of commodities for public consumption that contain radioactive substances. Annexes provide some examples of prolonged exposure situations and discuss the radiological protection quantities, radiation-induced health effects and aspects of the Commission's system of radiological protection relevant to prolonged exposure. Quantitative recommendations for prolonged exposures are provided in the report. They must be interpreted with extreme caution; Chapters 4 and 5 stress the upper bound nature of the following values: Generic reference levels for intervention, in terms of existing total annual doses, are given as < approximately 100 mSv, above which intervention is almost always justifiable (situations for which the annual dose threshold for deterministic effects in relevant organs is exceeded will almost always require intervention), and < approximately 10 mSv, below which intervention is not likely to be justifiable (and above which it may be necessary). Intervention exemption levels for commodities, especially building materials, are expressed as an additional annual dose of approximately 1 mSv. The dose limit for exposures of the public from practices is expressed as aggregated (prolonged and transitory) additional annual doses from all relevant practices of 1 mSv. Dose constraints for sources within practices are expressed as an additional annual dose lower than 1 mSv (e.g. of approximately 0.3 mSv), which could be approximately 0.1 mSv for the prolonged exposure component. An exemption level for practices is expressed as an additional annual dose of approximately 0.01 mSv.  相似文献   

10.
国际原子能机构(IAEA)在国际放射防护委员会(ICRP)第103号建议书的基础上,完成了《国际电离辐射防护与辐射源安全基本标准》(IBSS)的修订并于2014年发布,原来的实践与干预体系改变为现在的计划照射、应急照射和现存照射三种照射情况。关于应急照射情况的要求主要有:根据与源有关的辐射危险的性质和规模制定应急计划、应急程序和应急安排;参考水平用于应急照射情况下的防护和安全最优化;政府须确保建立和维护一个综合并协调的应急管理体系;对于公众照射,政府须确保在规划阶段制定防护策略并使其正当化和最优化;政府须制定关于管理、控制和记录应急人员在紧急情况下所受剂量的计划。IAEA保护人类和环境安全标准GSR第七部分《核与辐射应急准备和响应安全标准》是基于原安全标准丛书GS-R-2(2002)和IBSS修订发布的,本文给出了在要求、术语、概念等方面的变化。我国现行标准《电离辐射防护与辐射源安全基本标准》等效采用了1996版IBSS,在参考水平、公众应急防护行动准则、应急工作人员的受照控制等方面都与新IBSS不同,应及时开展研究并修订我国标准。  相似文献   

11.
The biological effectiveness of fission neutrons relative to low dose rate photon radiations with energies in excess of 400 keV lies in the range from 10 to possibly in excess of 100 depending upon the effect studied; in contrast to the quality factor used in radiological protection for those neutrons of about 10. However, for the majority of genetic effects, tumour induction and life shortening in rodents, the value would appear to lie in the region of 20 to 30. One consistent biological observation is that the effectiveness of photon radiation is decreased at low dose rates. Bearing in mind that human risk estimates have almost all been derived from high dose, high dose rate exposures, it does not seem likely that the current risks to humans from either photon or neutron radiation at low doses and low dose rates have been grossly underestimated. This conclusion is reached after making allowances for the possible effects of a revision of the dosimetry of the Japanese atomic bomb survivors.The recent ICRP recommendation that the quality factor for neutrons should be increased by a factor of two has to be seen in a context in which the concept used in the measurement and control of individual exposures to neutron radiation overestimates the dose limiting quantity also by a factor of about two or three. Therefore, there does not appear to be any urgency in altering the current techniques of controlling exposures to neutron radiation to accommodate the ICRP recommendation, particularly since the ICRP may revise the physical basis for the specification of quality factor in the not too distant future.  相似文献   

12.
放射防护领域的新进展   总被引:1,自引:0,他引:1  
郑钧正 《辐射防护》2016,36(6):393-407
根据国际辐射单位与测量委员会(ICRU)、联合国原子辐射影响科学委员会(UNSCEAR)和国际放射防护委员会(ICRP)等权威国际组织不断演进的新出版物,归纳揭示出电离辐射量体系、放射生物学效应和放射防护体系等构成放射防护三大重要基础的新进展;同时本文第四部分扼要评述影响面很广的热点课题医疗照射防护的新进展。  相似文献   

13.
ICRP放射防护基本建议书的演进及其启示   总被引:4,自引:1,他引:3  
不断演进的国际放射防护委员会(ICRP)的基本建议书,具体阐述了各个历史时期放射防护的总指导方针与原则,是国际组织和世界各国制定放射防护法规与标准的基本依据。ICRP基本建议书的最新更迭是,2007年底出版的第103号出版物——《国际放射防护委员会2007年建议书》取代了其第60号出版物。本文从放射防护体系,防护体系的应用,权重因子和标称危险系数的更新,剂量评价方法,放射防护最优化,医疗照射防护,环境的放射防护等7方面介绍了2007年建议书的更新特点;同时,从更新取决于认识的深化,完善防护体系没有止境,区别对待是重要的防护方针,正确运用剂量限值,培植安全文化等5方面讨论了建议书不断演进的启示。  相似文献   

14.
《Annals of the ICRP》2007,37(6):1-63
This report was prepared to underpin the Commission's 2007 Recommendations with regard to the medical exposure of patients, including their comforters and carers, and volunteers in biomedical research. It addresses the proper application of the fundamental principles (justification, optimisation of protection, and application of dose limits) of the Commission's 2007 Recommendations to these individuals. With regard to medical exposure of patients, it is not appropriate to apply dose limits or dose constraints, because such limits would often do more harm than good. Often, there are concurrent chronic, severe, or even life-threatening medical conditions that are more critical than the radiation exposure. The emphasis is then on justification of the medical procedures and on the optimisation of radiological protection. In diagnostic and interventional procedures, justification of procedures (for a defined purpose and for an individual patient), and management of the patient dose commensurate with the medical task, are the appropriate mechanisms to avoid unnecessary or unproductive radiation exposure. Equipment features that facilitate patient dose management, and diagnostic reference levels derived at the appropriate national, regional, or local level, are likely to be the most effective approaches. In radiation therapy, the avoidance of accidents is a predominant issue. With regard to comforters and carers, and volunteers in biomedical research, dose constraints are appropriate. Over the last decade, the Commission has published a number of documents that provided detailed advice related to radiological protection and safety in the medical applications of ionising radiation. Each of the publications addressed a specific topic defined by the type of radiation source and the medical discipline in which the source is applied, and was written with the intent of communicating directly with the relevant medical practitioners and supporting medical staff. This report consolidates that advice.  相似文献   

15.
ICRP94年人类呼吸道模型介绍   总被引:6,自引:0,他引:6  
周永增 《辐射防护》1996,16(4):278-289
本文简要介绍了国际放射防护委员会(ICRP)1994年发表的用于辐射防护目的的人类呼吸道模型,与ICRP以往的模型进行了比较,还讨论了ICRP94年人类呼吸道模型在实际中的应用。  相似文献   

16.
空勤人员辐射剂量的估算与测定   总被引:1,自引:0,他引:1  
1991年,ICRP建议将空勤人员列入职业受照人群;2002年,我国颁布实施了《空勤人员宇宙辐射控制标准》。本文介绍航空飞行高度上的辐射环境及空勤人员辐射剂量的估算方法和常用的测量手段,并比较了不同方法的计算和测量结果。  相似文献   

17.
本文详细介绍了美国核管理委员会(NRC)对轻水堆的设计目标基准的修订方案和策略,并在此基础上,考虑到我国核电厂址向内陆发展所致公众照射途径的变化,提出了需要明确核动力厂设计目标值的建议,以及应用现行辐射防护相关标准需要关注的问题:(1)ICRP第103号出版物从以前基于过程的实践和干预的方法发展为基于辐射照射情况性质(计划照射、应急照射和现存照射)的方法,应当注意区分不同的照射情况;(2)ICRP第103号出版物在数值上更新了当量剂量和有效剂量的辐射权重因子和组织权重因子,因此,实施剂量评估所采用的剂量转换因子也需要更新。  相似文献   

18.
This report compiles the various numerical protection level values published by the International Commission on Radiological Protection (ICRP) since its 1990 Recommendations (Publication 60). Several terms are used to denominate the protection levels: individual dose limit, 'maximum' individual dose, dose constraint, exemption level, exclusion level, action level, or intervention level. The reasons provided by the Commission for selecting the associated numerical values is quoted as far as available. In some cases the rationale is not totally explicit in the original ICRP report concerned; in such cases the Task Group that prepared the present report have proposed their own interpretation. Originally, this report was prepared by a Task Group at CEPN, a French research and development center, in behalf of IRSN, a French public expert body engaged in radiological protection and nuclear safety. It is published here with kind permission by CEPN and IRSN.  相似文献   

19.
对天然照射的控制问题   总被引:2,自引:0,他引:2  
夏益华 《辐射防护》2001,21(5):300-303,313
近年来,对天然照射的控制问题越来越受到社会各方面的关注。可能产生天然照射增高的所谓“NORM”问题的方面很多,本文在介绍国际上上对天然照射控制原则演变的基础上提出了在加强天然照射防护方面应注意的问题,特别介绍了ICRP第82号建议书中的有关定量参考水平。  相似文献   

20.
国际放射防护委员会(ICRP)提出在辐射防护中采用有效剂量当量,本文对能量在62keV 至10MeV 范围内的 X、γ射线,在不同的照射几何条件下,计算了有效剂量当量与自由空气场照射量或个人剂量仪读数的比值,并讨论了有关的应用问题。  相似文献   

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