居室中放射性污染调查与辐射剂量估算

目的 探讨不同类型房屋中放射性污染水平。方法 于2003年仡太原市某社区内监测了23间不同类型房屋的室内、外氡浓度及氡子体潜能γ剂量率，以及地面和墙壁表面氡析出率。同时还测定了室内自来水和煤制气中氡浓度，地下室、平房、楼房居室中来源于土壤和建材、室外空气、水、煤制气的放射性水平。最后估算了室内、外氡暴露的年有效剂量当量。结果 室内氡浓度、氡子体潜能γ剂量率均高于室外。地面氧析出率高于墙壁。自来水和煤制气中氡浓度均值分别为4.39～7．36Bq／m^3和11．55～51．07Bq/m^3。室内放射性污染主要来源于土壤和建材中的氡析出，其次是室外宅气中的氡及γ辐射，室内用水和煤气中氡及γ辐射的贡献很小。个体暴露于室内、外氡的年总剂量当量为1．94mSv。结论本次调查的所有膳室均符合我国《：室内空气质量卫生规范》的要求。调查结果为进一步研究居住环境中放射性污染奠定了基础。     

室内氡的来源、日变化规律及防治措施

目的 本研究旨在通过实验测量找出室内氡浓度的日变化规律及室内氡的主要来源,再通过改变测量条件,分析各测量条件下的测量结果,提出降低室内氡浓度的办法。方法 运用ERS-2-S型氡析出率仪测量各种条件下室内小时氡浓度,建筑物地基、周围土壤、建筑材料的氡析出率及室外空气中氡浓度。结果 房间密封时间长短对氡浓度的测量结果的影响较大,室内氡浓度呈现早上高,下午低的日变化规律;在关闭门窗隔绝室内空气的情况下,室内氡浓度主要来源于建筑材料的贡献;在打开门窗的情况下,对室内氡浓度的主要贡献是室外氡浓度。结论 对建筑物施工前地基进行抗开裂措施和防水处理、使用放射性核素符合国家标准《建筑材料放射性核素限量》要求的建筑主体材料和装修材料及加强室内日常通风量均能够有效地降低室内氡浓度。     

土壤氡与室内氡浓度关系的研究

目的了解土壤氡对底层房间的贡献.方法采用ERS1000和RAD7环境测氡仪测量土壤氡及析出率,根据析出率与室内氡关系公式计算了室内氡浓度的变化范围,对所得结果进行了实验验证.结果调查区域土壤氡浓度为(18 000±3 100)Bq·m-3;氡析出率为(8.15±5.55)Bq·m-2·s-1;混凝土地面的氡析出率为(0.72±0.19)Bq·m-2·s-1,普通混凝土结构房屋中氡浓度理论计算范围为11.5～42.4Bq·m-3.实际测量结果(18.9～40.6)Bq·m-3,预测值与实测结果一致.结论在土壤氡浓度低于20000Bq·m-3地区,采用传统建筑方式,不会引起室内氡浓度增高.     

室内氡的水平与控制措施

目的 验证北京市室内氡水平的分布,提出控制室内氡浓度若干途径。方法 以清华大学工程物理系室内环境质量评价中心测量的室内氡浓度数据与中国疾病预防与控制中心辐射防护核安全医学所、北京东城区卫生防疫站环卫科等单位在北京的测量数据相互印证,分析了北京市室内氡浓度的大致范围。结果 上述三家单位的氡浓度测量数据一致性比较好。结论 我国制定的"室内氡浓度行动水平"与发达国家制定的标准基本相同。在国家综合实力许可的情况下,应降低干预室内氡的行动水平,把氡致肺癌危险度降到最优化水平。加强通风、降低氡的析出率和建材控制等是室内氡的水平的有效控制措施。     

室内氡污染与肺癌

氡是一种自然发生的放射活性气体.U系(238U)放射性衰变时所释放的氡气广泛存在于室内和室外空气一中.大量的地下矿场和动物实验流行病学研究证实在吸烟和非吸烟人群中氧可诱发肺癌.因此,从泥土、水和建筑材料释放到室内空气中的氡已被认为是一种诱发肺癌的潜在性重要因素.本文献综述对氡的来源,室内氡的水平,流行病学研究,室内氡污染原理以及室内氡与肺癌发生的关系进行综述.     

建筑陶瓷地砖表面氡析出及其对室内空气中氡浓度的影响

目的 主要探讨建筑陶地砖表面析出的氡对室内环境空气中氡浓度的影响。方法 建立了一种采用局部静态法测量陶瓷表面氡析出率的测量方法,并根椐本实验模型推出了表面氡析出率的计算公式。结果 委托制作了系列高镭含量的建筑陶瓷砖样品,并测量了其表面氡析出率;研究了建筑陶瓷地砖镭含量同表面氡析出率的关系,估算了引入建筑陶瓷地砖对室内空气氡浓度的影响程度。结论 发现建筑陶瓷地砖的表面氡析出率小于0.003mBq·m^-2·s^-1,造成室内空气中氡浓度的增加量小于1Bq/m³。     

室内氡污染的研究进展

近年来,室内空气污染的研究已经逐步集中在氡及其子体和挥发性有机物上,该文就室内空气氡污染的研究现状作一综述,包括室内氡污染来源、影响室内氡浓度的因素、氡污染的健康效应和防氡降氡措施,为室内氡污染的研究提供理论依据。     

广州地区教学环境空气中氡浓度调查

目的 研究广州地区教学环境空气中氡浓度,探讨教学环境氡的来源.方法 于2005年3-4月,8-9月,运用瞬时测量和累积测量方法进行室内空气中的氡浓度测量,并调查教室面积、装修时间、通风条件对氡浓度的影响,昼夜、季节与氡浓度的关系.结果 广州地区教学环境室内空气中氡浓度为(34.2±21.17)Bq/m3,新建筑物室内空气中氡浓度[(36.6±25.5)Bq/m3]高于旧建筑室内氡浓度[(20.1±8.48)Bq/m3],夜晚室内空气中氡浓度高于白天,6:00-7:00为最高值(165.6Bq/m3),冬季室内空气中氡浓度[(54.2±15.11)Bq/m3]高于夏季室内氡浓度[(17.3±7.31)Bq/m3].结论 广州地区教学环境空气中氡浓度算术平均值在我国标准范围内,教学环境空气中氡浓度在外界条件改变时有差异.     

水氡的释放

水氡的释放孙军重庆市卫生防疫站６３００４２陈以彬四川省放射卫生防护所６１００４１近年来，国内外对室内氡研究较多，其主要研究方向为测定室内氧含量；考察室内氡含量的一系列影响因素，如房间通风量，建筑材料，以及氡进入室内的途径等；氡子体在室内空气中的行为。...     

西安市室内空气氡浓度水平及人体辐射暴露研究

目的 了解西安市室内氡浓度水平。方法 采用Model 1027连续测氡仪对西安市三环内室内氡浓度水平进行监测。室内氡浓度监测共选取西安市三环内样本数92个,每个采样点选取2~3个监测点,并且对监测点连续监测1 h,所有监测点的平均值即为该点的氡浓度水平。结果 西安市三环内室内氡浓度范围为3.70~525.40 Bq/m³,算术平均值为89.93 Bq/m³。冬季室内氡浓度水平高于春季。结论 除网吧外,西安室内空气氡浓度在国家规定范围之内,网吧室内氡浓度普遍偏高。     

黄山市环境辐射水平及居民受照剂量调查分析

目的研究黄山市环境辐射水平及居民受照剂量,为辐射防护和经济建设提供背景资料。方法采用FD-71型闪烁辐射仪,测量室内外、道路γ辐射剂量率;采用低本底闪烁测氡仪,测量氡浓度;采用γ能谱分析方法,测量建材中放射性核素226Ra、232Th、40K的含量。结果室内、室外、道路γ辐射剂量率均值分别为12.2×10-8Gy.h-1、8.5×10-8Gy.h-1、8.6×10-8Gy.h-1。地球γ辐射水平室内比室外高,平均比值为1.44,道路与室外的γ辐射水平差异无统计学意义。室内和室外宇宙射线辐射剂量率分别为2.7×10-8Gy.h-1和3.0×10-8Gy.h-1。室内、室外氡浓度均值分别为27.3 Bq.m-3和13.2 Bq.m-3。建筑材料除碳化砖及个别类型中的样品外,其他建材内、外照射指数均低于国家标准。结论黄山市环境辐射外照射所致居民人均年有效剂量当量为0.92mSv,其辐射水平属正常本底水平;室内、外氡浓度致居民受到的人均年有效剂量当量为1.88 mSv。在世界值范围内,传统建材放射性核素含量与世界建材典型值比较接近,其他建材有部分则高于世界建材典型值,应引起相关部门的注意。     

Indoor radon and well water radon in Virginia and Maryland

The domestic use of radioactive water has long been a cause for concern, but only a few studies have examined prolonged exposure to radionuclide concentrations found in natural settings. This paper reports on the indoor radon concentrations from 1,500 homes in northern Virginia and southern Maryland and well water radon from 700 homes in the same area. Indoor radon concentrations are almost all between 1 and about 40 pCi/L. The winter season shows the highest values with about 40% of the homes over the US EPA action level of 4.0 pCi/L. The summer season shows the lowest values with about 25% of the homes over this level. This seasonal variation is related to home ventilation. Waterborne radon in homes with private well ranges from about 100 pCi/L to about 8,000 pCi/L. In small homes, indoor radon can be significantly increased by outgassing of the home water supply, even at water radon levels of less than 10,000 pCi/L.     

Pollution of room air

In the last decade the significance of indoor air pollution to human health has increased because of improved thermal insulation of buildings to save energy: air turnover is reduced and air quality is impaired. The most frequent air pollutants are tobacco smoke, radioactive radon gas emanating from the soil, formaldehyde from furniture and insulation material, nitrogen oxides from gas stoves, as well as solvents from cleaning agents. The most important pollutants leading to health hazards are tobacco smoke and air pollutants which are emitted continuously from building materials and furniture. Such pollutants have to be eliminated by reducing the emission rate. A fresh air supply is necessary to reduce the pollutants resulting from the inhabitants and their activities, the amount depending on the number of inhabitants and the usage of the room. The carbon dioxide level should not exceed 1500 ppm.     

Prevention measures against radiation exposure to radon in well waters: analysis of the present situation in Finland

Naturally occurring radioactive elements are found in all groundwaters, especially in bedrock waters. Exposure to these radioactive elements increases the risk of cancer. The most significant of these elements is radon which, as a gas, is mobile and dissolves in groundwater. In Finland, water supply plants are obliged to carry out statutory monitoring of the water quality, including radon. Monitoring of private wells, however, is often neglected. In this paper, we outline the problem by reviewing the outcomes of the studies conducted in Finland since the 1960s. We also summarise the development of legislation, regulations and political decisions made so far that have affected the amount of public exposure to radon in drinking water. A review of the studies on radon removal techniques is provided, together with newly obtained results. New data on the transfer of radon from water into indoor air are presented. The new assessments also take into account the expanding use of domestic radionuclide removal units by Finnish households.     

个旧居民肺癌发病率与室内氡关系的探讨

目的 探讨云南个旧地区居民（不包括矿工和冶炼工）肺癌高发的原因。方法 应用固体核径迹探测器（简称SSNTD）方法对土壤、室内氡进行了测定。结果 发现纵贯个旧地区的个旧－小江断裂带提供了丰富的土壤氡的地下来源，在断裂带上测得土壤氡水平为世界土壤氡平均值的8．6倍，断裂带上的室内氡水平是远离断裂带室内氡水平的6．5倍。调查组室内氡平均值比对照组室内氡平均值高出44．5％。分组统计表明，室内氡水平越高，肺癌发病率（除一组例外）相应增高。结论 通过本次调查似乎可以认为肺癌发病率与室内氡水平有呈正相关的趋势。     

Indoor radon pollution in houses in the Apulian Region of Italy and evaluation of the probability of lung cancer in the population

BACKGROUND: Radon-222 is a gaseous radioactive chemical which can be transformed into other radioactive chemicals, defined as "products of decay" or "radon's daughter". The modality of radon penetration into the buildings depends on the convection motion created in the ground, which suck it back, so causing the penetration. The principal effect on human health is the increase risk of lung cancer, in proportion to the concentration and the time people spend indoors with exposure to radon. OBJECTIVES: The study proposed to estimate the expected cases of radon-induced lung cancer in the population of Apulia due to contamination by indoor radon. METHODS: The study used the data obtained in a national survey made by ANPA (National Environmental Protection Agency) and ISS (High Health Institute), with the collaboration of the Regional Reference Centres for the Control of Environmental Radioactivity (CRR). In the Apulia Region 310 families (5000 nationwide) were involved, which were selected so as to constitute a representative sample both of the region and the country. Appropriate instruments for the measurement of mean concentrations of indoor radon (passive nuclear trace monitors were installed in the homes of the sample families in two different periods of year). We evaluated the variations of indoor radon concentration in the houses during spring-summer and autumn-winter periods, observing a predictable increase in the latter period. We assessed concentrations in relation to: 1. architectural features and location, 2. construction year, 3. building material, 4. presence of windows. RESULTS: We found higher contamination in the oldest non-cement buildings and on the lower floors. In Lecce and Castrì di Lecce we found a mean radon concentration higher than the national and the regional mean, which is equivalent to annual exposure of 0.54 and 0.46 WLM respectively. For these levels we estimated that the expected cases of radon-induced lung cancer will be 1.5 in Lecce and 1.3 in Castrì per 10,000 inhabitants. CONCLUSION: The results of our investigations confirm that indoor radon pollution is a significant problem as it is one of the main causes of lung cancer. Hence, precautionary measures to reduce as much as possible exposure to indoor radon are highly recommended.     

哈尔滨工程大学室内氡浓度水平及评价

目的 了解哈尔滨工程大学室内氡浓度的水平,并进行剂量水平评价。方法 采用双滤膜法连续测量哈尔滨工程大学室内氡浓度,并对氡的危害进行评价。结果 哈尔滨工程大学室内氡及其子体对人体造成的年辐射剂量为1.48 mSv,略高于我国平均水平。结论 哈尔滨工程大学室内氡浓度偏高,可以从"截源"、"消散"两个方面来降低室内氡浓度。     

建筑材料表面析出氡的监测方法研究

目的 研究建筑装饰材料(简称建材)表面析出氡的监测方法，主要是为人们安全使用建材提供依据。方法 为了解常见建材表面的氡析出水平，采用自行研制的静电收集装置及驻极体收集装置。依不同环境及现场条件，对24间工作用房、1个演播厅及1个计算机房实施联合监测。结果 利用这两种装置配合使用的综合测量方法，可以得出满意的监测结果。结论 这种联合监测方法适用于现场的常规监测，其监测结果还可为室内场所环境的放射性危害分析、所采取的相应防治措施以及氡水平评价等服务。     

Indoor radon exposure and lung cancer risk: a review of case-control studies

BACKGROUND: Radon is a radioactive gas that tends to accumulate in indoor environment. A causal relationship between lung cancer and radon exposure has been demonstrated in epidemiologic studies of miners. The objective of this paper is to present the results of case-control studies of lung cancer risk associated with indoor radon exposure. METHODS: Case-control studies published since 1990 are included in this review. This type of protocol is particularly well suited for studying the relationship between indoor radon exposure and lung cancer risk, taking into account possible confounding factors such as tobacco smoking. The characteristics and results of these studies are summarized. The limitations associated with each of these studies are also discussed. RESULTS: The results of available studies are relatively concordant and suggest a positive association between lung cancer risk and indoor radon exposure with an estimated excess relative risk of about 6 to 9% per 100Bq/m3 increase in the observed time-weighted average radon concentration. The order of magnitude of this estimation agrees with extrapolations from miners but some studies may suffer from inadequate statistical power. CONCLUSION: At present, efforts are underway to pool together the data from the existing studies of indoor radon. This pooling analysis with thousands of cases and controls will provide a more precise estimate of the lung cancer risk from indoor radon exposure and explore the effect of modifying factors, such as smoking.     

南宁市医院室内氡浓度及γ辐射水平所致工作人员剂量

目的 了解南宁市医院放射科与核医学科室内氡浓度和γ照射量率水平,估算工作人员受照剂量,为辐射防护管理提供依据。方法 采用ATD累积氡探测器和FH40G环境X、γ剂量率仪测量室内外氡浓度和γ照射量率。结果 核医学、放射科地下和地面工作场所、工作人员和居民受照剂量分别是1.98 mSv、1.84 mSv、1.62 mSv、1.48 mSv和1.49 mSv。结论 核医学科工作人员受到的附加剂量主要与放射性同位素的用量与防护条件有关。放射科工作人员剂量增高的原因主要来自氡污染产生的内照射。