十堰市城区居民室内氡浓度调查结果与分析

目的 对十堰市城区居民室内氡浓度进行监测,分析居民室内氡浓度水平及影响因素。方法 从2019年4月到7月,采用RSKS标准型探测器对十堰市城区共计125户居民室内氡浓度进行测量并分析。结果 2019年所监测的十堰城区居民室内氡浓度结果呈偏态分布,范围为13.8～145 Bq/m³,M(P₂₅,P₇₅)为38.3(29.0,62.0) Bq/m³,居民因吸入氡及其子体产生的年均有效剂量估算值为0.52～5.50 mSv,M(P₂₅,P₇₅)为1.45(1.10,2.36) mSv,与相关文献一致;不同建筑结构(H=14.10,P<0.001)、楼层(H=24.41,P<0.001)和地区(H=8.963,P<0.05)均是居民室内氡浓度水平的影响因素,且差异均有统计学意义。结论 十堰市城区居民室内氡浓度小于国家标准限值,但在日常生活中还是需要注意采取合适的方法,尽量降低家中氡浓度。     

新建高层毛坯房室内氡水平及影响因素研究

[目的]了解新建高层毛坯房室内氡污染水平,分析毛坯房室内氡水平的主要影响因素。[方法]采用Model1027型连续测氡仪对11套新建高层楼房室内氡浓度进行连续检测。[结果]本次调查的毛坯房室内氡浓度为(108.073±62.074)Bq/m3;毛坯房高层室内氡浓度远低于低层室内氡浓度,地基土壤氡对新建高层毛坯房楼层较高室内氡浓度影响较小;与建筑材料表面积相比,建筑物内部体积变化对室内氡浓度的影响较显著。[结论]新建高层毛坯房室内氡浓度远高于我国居民装修住宅室内氡浓度水平。室内墙体粉刷、地面铺设瓷砖、楼层高度、建筑物表面积、体积是影响毛坯房室内氡浓度的主要因素。     

某社区居民住宅室内氡浓度水平调查与分析

目的 为了解不同建筑结构、不同年代、不同装修材料、在不同密闭与通风状态下居民住宅室内氡浓度水平,为保障公众健康提出有效的氡的数据资料。方法 使用连续测氡仪,测量室内氡浓度,采用单因素方差、Dunnett统计方法分析。结果 调查36户居民室内氡浓度,范围在0.2~199.3 Bq·m^-3,几何均数为30.6 Bq·m^-3,不同建筑结构室内氡浓度差异有统计学意义,不同年代建筑室内氡浓度差异有统计学意义,不同密闭与通风状态下室内氡浓度差别有统计学意义。结论 被调查居民住宅室内氡浓度都在正常范围内,氡浓度主要受建筑结构及通风状态影响。     

长春市室内氡浓度水平及变化规律

目的 调查分析长春市室内氡浓度水平及变化规律.方法 采用累积测量方法,在长春市居民住宅内布放CR-39固体核径迹探测器,布放周期为3m.结果 长春市室内氡浓度水平范围为12～ 529 Bq/m3,室内氡浓度算数均数为80.64 Bq/m3,几何均数为52.05 Bq/m3.约有80％测量点室内氡浓度在100 Bq/m3...     

西藏居室内氡浓度调查及所致居民剂量估算

目的 在国内城市室内氡呈上升趋势的背景下,为了获取现阶段西藏地区室内氡浓度水平,开展本次西藏地区室内氡浓度调查工作。方法 采用KF606B型固体核径迹氡累积探测器,对西藏自治区居室氡浓度进行测量,测量周期6～12个月。结果 西藏地区138间居室内氡浓度范围为14～119 Bq·m^-3,均值为（47.8 ±23.0） Bq·m^-3。氡浓度大于100 Bq·m^-3房间有5个,占总调查房间数的4%。居室内氡所致西藏地区居民有效剂量范围为0.46～3.89 mSv·a^-1,均值为1.56 mSv·a^-1。文章还对不同调查地区、城镇/农村、不同建筑类型和不同建筑年代居室内氡浓度进行了比较分析。结论 本次居室内氡浓度调查结果比上世纪八九十年代西藏地区测量结果有显著增高。     

银川市室内氡浓度调查及公众剂量估算

目的 初步调查银川市城乡住宅室内氡浓度水平及估算有效剂量。方法 采用固体核迹径法，选择银川市城市49户、农村18户，共计67间居室累积测量3个月以上。结果 银川市城乡室内氡浓度算术平均值为64 Bq/m³，几何均值为59 Bq/m³，中位数为57 Bq/m³，范围为25～172 Bq/m³，室内氡浓度大于100 Bq/m³的测量点占7.5%。农村室内氡浓度高于城市。室内氡浓度呈冬季最高，夏季最低的特点。室内氡所致银川市居民有效剂量为1.86 mSv/a。结论 本次银川市室内氡浓度调查结果比上世纪九十年代测量结果有显著上升，年有效剂量高于世界及全国平均水平。     

建筑陶瓷放射性水平及卫生学评价

目的　研究建筑陶瓷的放射性水平及其所贡献的有效剂量。方法　采集 91个建筑陶瓷成品 ,用能谱仪测2 3 2 Th ,2 2 6Ra ,40 K含量 ,布放CR - 39氡浓度探测器测室内氡浓度。结果　 91个样品中有 1 5个接近国家B类标准 ,用建筑陶瓷装饰的居室室内氡浓度比对照组高 1 5 4 4Bq/m3 (P <0 0 5 )。广东产瓷砖所致居民年有效剂量为最高 ,达 1 0 1mSv/a ,附加年有效剂量为 0 2 4 2mSv/a,约为国家标准限值的 2 4 % ,其余省、市瓷砖所致附加有效剂量小一些。结论　不同地区生产的建筑陶瓷放射性水平相差悬殊 ,有的建筑陶瓷接近B类产品标准 ,用于居室内装修时应谨慎。建筑陶瓷在一定程度上可使室内氡浓度有所增加     

苏州市区居民住宅内氡水平及其影响因素分析

目的 了解苏州市居民住宅内氡水平。方法 采用双滤膜法,选用标准Pu-239源校正后的FT-648型测氡仪,效率为0.8,以40L/min的空气流速采样15min,间隔1min后记数15min,读取结果,经公式换算,得出氡浓度的数据。结果 本次调查的135户住房中氡浓度为41.4 Bq/m³。楼层、房屋结构、居住时间及装修材料对居民室内氡水平的有影响。结论 苏州市居住宅室内氡水平与世界范围的40.0 Bq/m³相当,保持良好通风是室内降低氡浓度的有效措施。     

浙江省居室内氡浓度和γ辐射水平的初步调查

目的 初步了解浙江省居室内的氡浓度和γ辐射水平及其分布特性,估算这两类辐射所致居民的受照剂量。方法 采用固体核径迹方法和热释光剂量方法测量氡浓度和γ辐射水平;根据地级市行政区域划分,随机抽取共490个卧室或客厅开展3个月以上的累积测量;在其中75个房间开展6个月以上测量以观察两类辐射水平的季节性变化;在开展调查过程中记录建筑物的结构、建筑年代、通风情况和楼层等信息。结果 全省居室内氡浓度和γ辐射水平均值为29.3 Bq·m^-3和105.8 nSv·h^-1,所致公众的平均年有效剂量分别为0.77和0.74 mSv;新建居室内的氡浓度较高,别墅内氡浓度明显高于其他类型的建筑物,居室内氡浓度水平随通风时间减少而升高;室内氡浓度和γ辐射水平没有明显的相关性,且随季节变化也不明显。结论 当前浙江省居室内的平均氡浓度和γ辐射水平虽然不高,但室内氡浓度已有增高的趋势,值得关注与控制。     

个旧市郊室内氡、钍射气浓度和地面γ辐射水平初步调查

目的调查个旧地区居室内氡（^222Rn）、钍射气（^220Rn）及其子体水平，明确钍射气的剂量贡献。方法考虑住宅类型和地理分布因素，从个旧市郊某村选取建筑结构有代表性的50户住宅的主卧室，采用氡-钍射气鉴别探测器测量氡、钍射气浓度，用沉积率装置测量钍射气子体浓度。其中14间居室采用连续性氡测量探测器和α谱氡、钍射气鉴别探测器测量氡、钍射气浓度，空气采样滤膜结合CR-39探测器测量钍射气衰变产物浓度，碘化钠闪烁计数器测量地表γ剂量率。结果50间居室的氡浓度为32～498Bq／m^3，平均136Bq／m^3；钍射气浓度为39～7908Bq／m^3，平均3297Bq／m^3；钍射气子体浓度为2．0～23．9Bq／m^3，平均10．2Bq／m^3。钍射气子体衰变产物致居民年平均有效剂量大于氡子体衰变产物的平均年有效剂量（2．9mSv vs 1．6mSv）。结论个旧市郊部分居室室内钍射气及其子体浓度高，钍射气子体的剂量贡献要高于氡子体的剂量贡献。在个旧开展氡致肺癌危险评价研究应当考虑钍射气子体的剂量贡献。     

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     

Intercomparison of retrospective radon detectors.

We performed both a laboratory and a field intercomparison of two novel glass-based retrospective radon detectors previously used in major radon case-control studies performed in Missouri and Iowa. The new detectors estimate retrospective residential radon exposure from the accumulation of a long-lived radon decay product, (210)Pb, in glass. The detectors use track registration material in direct contact with glass surfaces to measure the alpha-emission of a (210)Pb-decay product, (210)Po. The detector's track density generation rate (tracks per square centimeter per hour) is proportional to the surface alpha-activity. In the absence of other strong sources of alpha-emission in the glass, the implanted surface alpha-activity should be proportional to the accumulated (210)Po, and hence to the cumulative radon gas exposure. The goals of the intercomparison were to a) perform collocated measurements using two different glass-based retrospective radon detectors in a controlled laboratory environment to compare their relative response to implanted polonium in the absence of environmental variation, b) perform collocated measurements using two different retrospective radon progeny detectors in a variety of residential settings to compare their detection of glass-implanted polonium activities, and c) examine the correlation between track density rates and contemporary radon gas concentrations. The laboratory results suggested that the materials and methods used by the studies produced similar track densities in detectors exposed to the same implanted (210)Po activity. The field phase of the intercomparison found excellent agreement between the track density rates for the two types of retrospective detectors. The correlation between the track density rates and direct contemporary radon concentration measurements was relatively high, considering that no adjustments were performed to account for either the residential depositional environment or glass surface type. Preliminary comparisons of the models used to translate track rate densities to average long-term radon concentrations differ between the two studies. Further calibration of the retrospective detectors' models for interpretation of track rate density may allow the pooling of studies that use glass-based retrospective radon detectors to determine historic residential radon exposures.     

Factors underlying residential radon concentration: results from Galicia, Spain

Radon causes lung cancer when inhaled for prolonged periods of time. A range of factors influence residential radon concentration and this study therefore sought to ascertain which dwelling-related factors exert an influence on radon levels. A cross-sectional study was conducted from 2001 to 2003 which analyzed 983 homes of as many subjects randomly selected from the 1991 census. Sampling was carried out by district and stratified by population density to ensure that more detectors were placed in the most heavily populated areas. Radon concentration and different dwelling characteristics were measured in each of the homes selected. Bivariate and multivariate analyses were performed to ascertain which factors influenced radon concentration. The geometric mean of radon concentration was 69.5 Bq/m3, and 21.3% of homes had concentrations above 148 Bq/m3. Factors shown to influence radon concentration in the bivariate analysis were: age of dwelling; interior building material; exterior building material; and storey on which the detector was placed. Explanatory variables in the multivariate analysis were: age of dwelling; number of storeys; distance off floor; and interior building material. The model was significant, but the variability explained was around 10%. These results highlight the fact that the study area is an area of high radon emission and that factors other than those directly related with the characteristics of the dwelling also influence radon concentration.     

湖北省2010-2013年艾滋病时空分布特征分析

目的 了解2010-2013年湖北省HIV/AIDS的时空分布特征,为艾滋病防控提供科学依据。方法 采用GeoDa软件进行空间自相关分析,采用SatScan 9.2软件进行时空扫描统计分析,最后运用地理信息系统实现结果的可视化。结果 2010-2013年湖北省累计报告HIV/AIDS病例6 952例,累计报告病例数的全局Moran''s I指数为0.266,P<0.05,表明2010-2013年湖北省HIV/AIDS存在正向空间自相关。全局Moran''s I值在2010-2013年逐年增加,且P值均<0.05,说明2010-2013年湖北省HIV/AIDS全局空间聚集性呈上升趋势。局部相关自相关分析发现湖北省艾滋病“高高”聚集区主要位于武汉市,2010-2013年聚集区数目逐年增加,且从武汉市区向周边县区扩散。时空扫描分析显示武汉、黄石、鄂州、咸宁的19个区（县）为一级时空聚集区,时间跨度为2012-2013年,辐射半径为60.01 km（LLR=625.14,RR=3.23）,结果具有统计学意义。结论 2010-2013年湖北省HIV/AIDS空间变化具有规律性,全局空间聚集性逐年增强,“高高”聚集区从武汉市区逐年向周边区（县）扩散,武汉及其周边区（县）为湖北省近几年艾滋病防控的重点区域。     

Radon concentrations in elementary schools in Kuwait

Measurements of indoor radon concentrations were performed in 25 classrooms in the capital city of Kuwait from September 2003 to March 2004 using track etch detectors. The investigation was focused on area, ventilation, windows, air conditioners, fans, and floor number. All the schools have nearly the same design. Mean indoor radon concentration was higher for case subjects (classrooms) than for control subjects (locations in inert gas, p < 0.001). The mean alpha dose equivalent rate for case subjects, 0.97 +/- 0.25 mSv y, was higher than the radiation dose equivalent rate value of control subjects, 0.43 +/- 0.11 mSv y. The average radon concentrations were found to be 16 +/- 4 Bq m for the first floor and 19 +/- 4.8 Bq m for the second floor after subtraction of the control. These values lead to average effective dose equivalent rates of 0.40 +/- 0.10 and 0.48 +/- 0.12 mSv y, respectively. The equilibrium factor between radon and its progeny was found to be 0.6 +/- 0.2.     

基于ESDA的湖北省新冠肺炎疫情分析

目的 分析湖北省新型冠状病毒肺炎疫情趋势及时空聚集性,为防控工作提供依据。方法 收集湖北省1月22日—3月25日新冠肺炎发病、死亡与治愈数据,描述疫情趋势,并通过GeoDa1.14.0软件进行空间自相关分析。结果 2020年1月22日 - 3月25日期间,湖北省共报告新冠肺炎67 801例,新增确诊病例数总体呈先上升后下降趋势,2月12日当天新增人数激增;累计确诊和死亡人数较高地区集中在湖北省东北部,武汉市为确诊及死亡人数最多的地区;湖北省累计确诊全局自相关不显著（Moran’s I≠0,P＞0.05）,累计死亡则在1月22日存在全局空间负相关（Moran’s I = - 0.01306,z = - 1.7797,P = 0.01）,此后全局自相关不显著（P＞0.05）;累计确诊及死亡人数局部空间自相关均存在显著聚集与异常情况（P＜0.05）,武汉市呈“高—低”异常,其周围地区（黄冈市、鄂州市、黄石市）呈“低—高”异常。结论 湖北省新冠肺炎疫情未存在显著的空间聚集性,武汉市作为疫情高值区未发生转移。建议 湖北省的防控工作仍应将武汉市作为重点,复工复产要采取差异化策略,应当分区、分时进行。     

Role of the number of stories in the radiation-sanitary assessment of residential buildings

Upon long-term exposure, the radioactive gas radon-222 and its decay products in increased doses adversely affect human health. Since the human being spends about 65% of his time in the buildings, it is necessary to evaluate air radiation purity in the rooms, which can be obtained by making a sanitary radiological survey of residential buildings. The scope of the rooms in many-storeyed buildings to be examined can be considerably reduced if the regularities in radon distribution are known. This paper deals with searches for regularities in the distribution of radon levels by the floors of many-storeyed buildings in Tomsk. The room air concentrations of radon were measured for 18 residential buildings with tract detectors upon 1-3--month exposure. The findings showed a different pattern in the distribution of radon levels by the floors in relation to the structural features of a building and to the type of a building material. The wooden and slag-concrete buildings show a 2-3--fold increase in radon levels on the lower floors as compared to the upper ones. A statistical analysis of measurements in the bearing-wall and brick buildings revealed no association of the concentration of radon with the level of a floor, the distribution is near-uniform with 15-30% standard deviation, which is within the limits of measurement error.     

Residential radon and risk of lung cancer: a combined analysis of 7 North American case-control studies

BACKGROUND: Underground miners exposed to high levels of radon have an excess risk of lung cancer. Residential exposure to radon is at much lower levels, and the risk of lung cancer with residential exposure is less clear. We conducted a systematic analysis of pooled data from all North American residential radon studies. METHODS: The pooling project included original data from 7 North American case-control studies, all of which used long-term alpha-track detectors to assess residential radon concentrations. A total of 3662 cases and 4966 controls were retained for the analysis. We used conditional likelihood regression to estimate the excess risk of lung cancer. RESULTS: Odds ratios (ORs) for lung cancer increased with residential radon concentration. The estimated OR after exposure to radon at a concentration of 100 Bq/m3 in the exposure time window 5 to 30 years before the index date was 1.11 (95% confidence interval = 1.00-1.28). This estimate is compatible with the estimate of 1.12 (1.02-1.25) predicted by downward extrapolation of the miner data. There was no evidence of heterogeneity of radon effects across studies. There was no apparent heterogeneity in the association by sex, educational level, type of respondent (proxy or self), or cigarette smoking, although there was some evidence of a decreasing radon-associated lung cancer risk with age. Analyses restricted to subsets of the data with presumed more accurate radon dosimetry resulted in increased estimates of risk. CONCLUSIONS: These results provide direct evidence of an association between residential radon and lung cancer risk, a finding predicted using miner data and consistent with results from animal and in vitro studies.     

Estimate of annual average radon concentration in the normal living area from short-term tests

Most residential radon guidelines refer to annual average radon concentration in the normal living area. However, decisions on whether a house needs mitigation are usually based on short term radon tests. Depending on where detectors are placed and when tests are performed, results of those measurements can differ significantly from the annual average radon concentration in the normal living area. We provide a practical method based on survey results in 5486 Canadian houses to estimate annual average radon levels from results of screening tests. The average ratio of radon concentration in the basement to that of the upper floors in a house is determined, and the average relative seasonal variations of radon levels in the basement and of the upper floors are identified. Based on these relative quantities, estimate factors are derived for four different combinations of detector location and the living area and tabulated for different calendar periods of radon testing. The annual average radon level can be estimated by multiplying the result of a short-term screening test with the appropriate estimate factor given in this study.