阿坝州环境氡及氡子体浓度测量

阿坝州环境氡及氡子体浓度测量刘怡刚，秦木确，邓显国，邓福美，周致熙，张传富氡及其子体对人体的危害已被众多的研究所证实［１］［２］。那么，如何抵御或降低其对人类的危害，也就成为目前人们对氡及子体研究的重点。作者在阿坝州境内进行了大范围、多种环境条件下的...     

海南省西部地区氡及其子体浓度水平调查

氡是室内空气中最重要污染物之一,因此,加强对环境空气中氡及其子体浓度的监测工作是十分必要的。     

氡及其子体研究动态

氡及其子体是天然放射性铀系、钍系产生的,是人类受天然辐射的主要来源之一,每年约为1.3mSv,占天然辐射的54%,其中室内氡的贡献约为1mSv^[1]。     

我国长江口区域氡及其子体水平调查研究

我国长江口区域氡及其子体水平调查研究王维，刘望伟，邱箕扬（上海市宝山区卫生防疫站，上海２０１９００）杜开如，顾芳，钱志林，郭玲，虞凤英，俞云珍（上海市放射医学研究所）我国的长江口区域主要包括工业发达、人口密集的上海宝山、长江出口处崇明岛和江苏省南通市...     

本溪某地下商场内氡及其子体的浓度

本文简述用双滤膜法和三段法测量某地下商场内氡及其子体浓度的结果，测量结果和剂量估算表明，该地下商场工作人员所受氡气体内照射剂理仍在正常本底范围内，不会对工作人员造成不利于健康的影响。     

矿山粉尘和氡及氡子体的危害及其影响因素

尾矿处理产生的粉尘和井下的放射性物质是矿山危害工人健康的重要因素。我们通过现场职业卫生学调查和场所中职业病危害因素检测,对辽宁某金属矿山的破碎站、运输皮带附近的空气进行了粉尘浓度检测,检测结果显示,部分检测点的粉尘浓度>3 mg/m³,超过国家标准限值;25.32%的尾矿的粒度<15μm,属于可吸入粉尘;粉尘主要成分为SiO₂和Fe₂O₃。我们通过分别对崩落法、充填法开采的4座矿山的氡气及氡子体浓度检测,发现充填法开采的矿山(A、B)的氡及氡子体浓度远低于崩落法开采的矿山(C、D)的浓度。提示,许多矿山工人的健康状况受到工作环境影响,矿山企业应采取有效的措施改善工作环境,做好职业病防护和预防工作。     

苏州市部分地下商场氡及其子体水平的测定

苏州市部分地下商场氡及其子体水平的测定张友九俞荣生＊殷文红＊胡晓盘（苏州医学院，苏州２１５００７）我们选择了５家地下商场和一个暂未被开发利用地下室，对其中的氡及其子体浓度进行了监测，现报告如下：１调查方法氡浓度采用双滤膜法〔１〕。测量装置用２２６Ｒａ...     

海南省室内外空气中氡及其子体水平调查

海南省室内外空气中氡及其子体水平调查曾庆祥陈学胜李燕黄兆慧林智邓志宏张福彩刘爱华钟蔚文郭健杨旭（武汉市卫生防疫站，武汉４３００２２）人类生活在自然环境中不可避免地受到环境辐射，这些辐射有８０％来自天然辐射，而天然辐射剂量中又有３５％是氡及其子...     

涪陵地区环境氡及其子体水平与所致剂量调查

为摸清涪陵地区居室内外环境氡及其子体浓度和居民受照剂量水平,我们按照统一方案要求于1989年在其五县市开展了调查,现报告于下。调查与测量方法 1.采样点布置原则,按县市为单位,在政府所在地城镇和部分区乡及风景区设点调查测试。各县市设点八个以上。 2.采样与测量,用国产Ⅰ号滤膜和英国产1355B型空气采样器采集呼吸带高度的空气样品,     

室内氡及氡子体的卫生学调查及致癌效应研究

天然放射性元素-铀、镭广泛地存在于自然界的土壤和岩石中,由于镭的衰变所形成的放射性气体(Ｒｎ—222)通过岩石裂缝、土壤间隙不断向空气中释放,成为人类本底辐射的重要来源。根据ＵＮＳＣＥＡＲ1993年报告书[1],人均年有效剂量当量为24ｍＳｖ,其中氡和氡子体的辐射造成的剂量贡献为12ｍＳｖ,占一半。从剂量学的观点来考虑,氡的短寿命子体是造成人体内照射剂量的最主要部分。已知氡有27种同位素,其中于人群健康密切相关的是222Ｒｎ,它是238Ｕ蜕变链的组成元素。218ＰＯ、214Ｐｂ、214Ｂｉ、214Ｐｏ是在蜕变过程中产生的4个短寿命的氡子体。…     

Comparative analysis of radon,thoron and thoron progeny concentration measurements

This study examined correlations between radon, thoron and thoron progeny concentrations based on surveys conducted in several different countries. For this purpose, passive detectors developed or modified by the National Institute of Radiological Sciences (NIRS) were used. Radon and thoron concentrations were measured using passive discriminative radon-thoron detectors. Thoron progeny measurements were conducted using the NIRS-modified detector, originally developed by Zhuo and Iida. Weak correlations were found between radon and thoron as well as between thoron and thoron progeny. The statistical evaluation showed that attention should be paid to the thoron equilibrium factor for calculation of thoron progeny concentrations based on thoron measurements. In addition, this evaluation indicated that radon, thoron and thoron progeny were independent parameters, so it would be difficult to estimate the concentration of one from those of the others.     

北京新镇地区室外氡子体水平调查

目的 调查北京新镇地区室外氡子体浓度水平及其变化规律,并估算其所致当地居民有效剂量。方法 运用德国BWLM-Plus-s、南华NR-200A和北大RPMD-SF01氡子体连续测量仪测量空气中氡子体浓度。结果 测量时间内新镇地区的室外平衡当量氡浓度平均值为9.1 Bq/m³,范围值为0.4~27.5 Bq/m³;室外氡子体致居民有效剂量为149 μSv,其中霾天附加剂量为9 μSv。结论 大气氡子体浓度受天气和气象因素影响,呈现上午高下午低的日变化规律;秋冬季较高,春夏季较低的季节变化规律。大气氡子体浓度霾天高于非霾天;霾可增加当地居民所受室外氡子体照射的有效剂量约6%。     

Dosimetry of radon progeny deposited on skin in air and thermal water

It is held that the skin dose from radon progeny is not negligibly small and that introducing cancer is a possible consequence under normal circumstances as there are a number of uncertainties in terms of related parameters such as activity concentrations in air and water, target cells in skin, skin covering materials, and deposition velocities. An interesting proposal has emerged in that skin exposure to natural radon-rich thermal water as part of balneotherapy can produce an immune response to induce beneficial health effects. The goal of this study was to obtain generic dose coefficients with a focus on the radon progeny deposited on the skin in air or water in relation to risk or treatment assessments. We thus first estimated the skin deposition velocities of radon progeny in air and thermal water based on data from the latest human studies. Skin dosimetry was then performed under different assumptions regarding alpha-emitting source position and target cell (i.e. basal cells or Langerhans cells). Furthermore, the impact of the radon progeny deposition on effective doses from all exposure pathways relating to ‘radon exposure’ was assessed using various possible scenarios. It was found that in both exposure media, effective doses from radon progeny inhalation are one to four orders of magnitude higher than those from the other pathways. In addition, absorbed doses on the skin can be the highest among all pathways when the radon activity concentrations in water are two or more orders of magnitude higher than those in air.     

湛江市部分住房室内外空气中氡浓度测定

采用活性炭吸附闪烁法测定了湛江市部分住房室内、外空气中的平衡当量氡浓度。结果表明 ,住房室内、外空气中平衡当量氡浓度平均值分别为 2 5 2 7Bq/m3 和 14 6 8Bq/m3 ,室内空气中平衡当量氡浓度显著高于室外 (P <0 0 1) ;不同装饰材料的住房室内空气中平衡当量氡浓度各有差异 ,其中以花岗岩为装饰材料的住房室内平衡当量氡浓度 (31 18Bq/m3 )为最高 ,水泥地板住房 (14 71Bq/m3 )最低     

地热田高氡建筑治理与效果评价

目的 探讨地热田高氡房屋氡的来源与治理.方法 α径迹探测器(ATD)分冬夏两个季节测量室内和土壤中的氡浓度.采用γ能谱法测量房屋主体建材放射性核素含量;采用6150 AD/6HX-γ剂量率仪测量房屋主体建材的外照射剂量率;对其中一栋房屋实施土壤减压技术的降氡改造.结果 夏冬季32个房间氡浓度均值分别为(106.4±63...     

Cost evaluation of control measures for indoor radon progeny

Based on assumed conditions within a typical U.S. home, annualized costs for reducing indoor airborne radon progeny concentrations have been calculated for a variety of methods of control. These analyses were limited to methods for control in existing homes. Control through modified construction techniques was not evaluated. Methods assessed included increased air circulation, increased ventilation, particle removal using electrostatic precipitation and unipolar ion generation, and the application of sealants to room surfaces. Although surface sealants proved to be reasonably cost-effective per person- sievert dose reduction, such sealants are prone to cracking and the durability of their effectiveness is questionable. Use of ceiling fans for increased air circulation and particle deposition appears to be least cost-effective, but this method may be attractive in some cases for reasons of comfort. The use of unipolar ion generators appears to be the best approach from the standpoint of cost effectiveness. These devices are also easy to install and are esthetically readily acceptable.     

土壤氡测定的影响因素探讨

目的 探讨土壤氡的测定方法,试图找出影响土壤氡测定结果准确性相关因素,为制定有效的测定方法提供依据。方法 采用抽气-电离室法。结果 土壤氡浓度随采样体积增加而增加;在一定范围里也随测量深度而增加;采样深度达60cm以上时,土壤氡浓度变动较小;抽气时间影响不太明显;微波会对结果有严重影响;雨后测定结果偏低;植被对测定结果有一定的影响。测量仪器用干燥剂受潮使测定结果降低。结论 采样体积、深度、微波振动、土壤湿度、植被等因素影响测量结果,选择最佳采样和测量条件,才能较好地保证测定结果的准确性。     

Simulation of the radon and radon progeny detection by silicon photodiodes

The use of silicon photodiodes for field radon measurements requires the utilization of measuring cells for protection against environmental electromagnetic fields. It is very important to study and optimize the impact of geometry conditions (dimensions of the measuring cell) on the photodiode detection efficiency that can be reduced more than 10-30 times. Two models (for volume-distributed nuclides around the detector and for radon progeny deposited on the diode surface radon progeny) were applied for simulation of the photodiode detection in measuring cells of different sizes. Their use allows an optimal choice of the most appropriate cell regarding the measurement conditions. Thus, for soil gas measurements cells we use a cell of 3.6 cm in diameter by 20 cm in height; for determination of the radon exhalation rate we use a cell of 16 cm in diameter by 14 cm in height; and for measurements in dwellings and large spaces we use cells larger than 20 cm and lower than 4 cm.     

Measurement of the equilibrium factor between radon and its progeny in the underground mining environment

A scintillation cell and a portable radiation spectrometer for radon progeny were respectively employed to measure the concentration of radon and that of its progeny in the underground gold mine environment. The measured concentrations were subsequently used to calculate the equilibrium factor between radon and its progeny. The results obtained indicate that various locations underground have different values of radon concentration and ratios of radon concentration to its progeny concentration. The differences can be ascribed to variations in grades of uranium at different locations and to some environmental factors such as ventilation, particle concentration, and the deposition of the progeny on surfaces or on the atmospheric aerosol.     

汕头市环境中氡水平及所致居民剂量的分析

本文报道了汕头市室内外环境中氡土气浓度及其子体潜能浓度。研究结果显示：本市环境天然辐射水平较高,室内外氡浓度分别为２００４、１６０５Ｂｑ／ｍ３,土气浓度分别为４１８５、３１１５Ｂｑ／ｍ３,氡子体分别为０００２５４、０００２６８ＷＬ,土气子体分别为０００３３１、０００２４５ＷＬ。汕头市居民吸入氡土气及其子体所致的年有效剂量当量为１２６ｍＳｖ,其中２２２Ｒｎ及其子体贡献了０９０３ｍＳｖ,即氡及其子体所贡献的年有效剂量当量占７５％,较接近于温带地区而高于全球正常本底地区（０９７ｍＳｖ）的水平