防氡墙面漆:居室涂料的新宠

高科技专利产品--经典2000防氡墙面漆,通过添加有吸收和阻挡射线的稀土化合物,将射线能量转变为无害的热能从而消除放射性;同时它能够通过施工后形成的致密保护膜,为墙体提供有效的密封,防止氡气从墙体逸出。“密封”和“吸收”的结合起到了很好的防氡效果,为广大消费者提供了环保、健康的保证。由此,防氡墙面漆已经成了居室涂料的新宠。上个世纪60年代末期,人们发现了室内氡的危害,氡对人体的辐射伤害占到了人体所受全部环境辐射伤害的55%以上。这项研究结果引起了人们的高度关注,在自己的居家生活中如何免遭隐形杀手--氡的伤害,成为人们在…     

室内氡辐射的检测与防护

简要介绍了室内氡的危害,氡的来源及检测方法,并在此基础上针对不同的氡源提出了阻断污染源的方法     

对室内空气中氡的防治

随着生活水平的提高和环保意识的加强，人们越来越关注自己的生活和工作空间。但是在谈及室内环境污染时，大家容易马上联想到甲醛、苯或者射线的危害，而忽略了氡气。实际上氡气是存在于室内空气中的最危险的污染气体之一。研究表明，氡气普遍存在于我们的生活环境中，它无色无味，但衰变时产生的α粒子，在人体所受到的全部环境辐射中占到55％以上，对人体健康威胁很大。但也大可不必谈“氡”色变，只要我们对氡有了正确的认识，知道如何选择合格的建材来构筑我们的房屋，知道如何防护，那么，氡也就没什么可怕的了。     

对室内氡污染物的浅谈

文章阐述了人类赖以生存的环境中氡的来源、性质,进入人体的途径及致病机制和主要的危害,提出了为减少氡所带来的危害需采取的补救措施和降低室内氡的方法。     

防氡防辐射水泥砂浆的研究

通过在水泥砂浆中加入重晶石、沸石、氧化铁粉、高铝水泥、石膏等原料,探讨防氡、防辐射的最佳途径。研究表明在水泥砂浆中掺加高铝水泥的防氡、防辐射的总体效果最好,即使掺加普通的建筑材料,如石膏也有一定的防氡、防辐射功效。优选和试验防氡防辐射材料对水泥防氡防辐射能力和性能的影响。     

（二）谈室内环境中的氡污染问题

本文就室内环境中氡气的来源、对人体的危害及氡的防治等进行了较为详细的阐述。     

室内空气中氡的危害和控制

针对我国室内空气中氡的实际情况，从氡的理性特征、来源水平、危害几方面进行了论述，介绍了世界各国对室内氡的控制标准，提出了控制室内空气中氡的有效方法。     

新扩建民用建筑室内氡预防和防治

继 18世纪的工业革命煤烟污染 ,19世纪石油和汽车工业发展带来光烟雾污染之后 ,人类又进入以室内空气污染为主要标志的第三代污染时期。国际上公认 ,室内污染是对公众健康危害最大的环境污染因素。室内有害气体的含量比室外高 10～ 10 0倍。而室内有害气体之一的氡被世界卫生组织列为致癌的“第二大杀手”。1　氡的演变镭衰变产生自然界唯一无色无味的天然放射性惰性气体—氡 ,氡经过数天继续衰变产生了一些金属子体 :钋— 2 18,铅— 2 18,铋— 2 14 ,钋— 2 14 ,这些放射性金属粒子 ,易在空气中形成溶胶 ,被人的呼吸系统截留 ,产生内照射 ,…     

室内氡的危害及控制措施

介绍了氡的性质以及室内氡的主要来源，特别强调了氡对人体的危害，进而介绍了国内室内氡浓度控制的规范与标准，并根据国家标准和它的四大来源，提出了相应的解决办法和防治措施，如不要将居民住宅建造在地质断裂带或工业废渣堆场上，选择符合国家标准的建筑材料来装修等，以保证人的身体健康。     

室内氡污染的危害及防治

简要介绍了氡的产生和氡污染的来源以及室内氡浓度的影响因素,结合氡的物理化学性质分析了室内氡污染对人体健康的危害,并针对室内氡污染的来源具体阐述了室内氡污染的控制措施和治理方法,以期创造健康的室内环境。     

Influence of ventilation on indoor radon level

Detailed radon measurements were conducted at different residential units in Hong Kong in winter time when air-conditioners were off and also in summer time when air-conditioners were on. Ventilation rates were measured concurrently to investigate the influence of ventilation on indoor radon level. The ratio of indoor radon level to outdoor radon level was plotted against ventilation rate, and it was found that a critical value existed after which the indoor radon level could be considered identical to the outdoor level. This result is important for use in ventilation design to reduce indoor radon pollution.     

Spatial indoor radon distribution in Mexico City

We present a spatial analysis of residential radon concentrations in the Mexico City Metropolitan Area, which we intend to use to assign radon exposure in an ongoing case-control study. As part of a probabilistic household survey, carried out between May and June 1999, 501 dwellings were selected for indoor placement of solid state nuclear track detectors (LR 115) in a cup array over a period of approximately 90 days. As part of the sampling design, the city was grid partitioned into nine zones and a sample of dwellings was selected in each zone. All zones were simultaneously surveyed. The stratified sampling design allowed us to obtain radon geometric means, adjusted for household characteristics, week of detector placement and number of days of measurement for these zones. Additionally, adjusted geometric means were estimated for the 100 census tracts surveyed and this information was used to obtain a more detailed spatial distribution of residential radon levels through kriging interpolation and surface contouring. Radon levels depended on the room of placement, the floor level and the ventilation habits but not on building materials. Regarding the city zone, the highest adjusted geometric mean was found in the southwest (136 Bqm(-3)), where 46% of the households had an estimated radon level in excess of 200 Bqm(-3). In the rest of the city, the geometric mean concentration ranged between 41 and 98 Bqm(-3). A more detailed spatial distribution showed that, in general, most of the eastern and middle zones of the city had estimated radon geometric means below 74 Bqm(-3), while the western ones had geometric means above this concentration. Very high geometric means, exceeding 111 Bqm(-3) and even reaching 288 Bqm(-3), are estimated for some areas located in the southern and western zones of Mexico City. The obtained spatial distribution shows that the areas with very high estimated residential radon concentrations are close to inactive volcanic mountains. We believe that the geo-statistical techniques, we have used, offer reasonably good estimates of the average spatial residential radon distribution in Mexico City under average ventilation in homes. The use of this indirect approach for radon exposure measurement in epidemiological studies is an inexpensive alternative to direct radon exposure measurement but may be subject to non-differential misclassification error. The effect of such error on the detection of a real increase in lung cancer risk from indoor radon remains to be determined.     

Studies of high indoor radon areas in Finland

Solid state nuclear track detectors were used in a regional survey of radon in indoor air. The study area comprises seven rural municipalities and two towns in an area of 80×50 km² with a population of about 65,000. Measurements were made in 754 houses in 31 subareas.The highest and lowest subarea means were 1,200 Bq/m³ and 95 Bq/m³, respectively. The estimated mean for the whole area was 370 Bq/m³. The concentrations 2,000 Bq/m³ and 800 Bq/m³ were exceeded in 32 and 90 houses, respectively.The present lung cancer incidence does not differ significantly from the national mean.     

The Italian national survey of indoor radon exposure

An investigation is being developed by the Camitato Nazionale per la Ricerca e per lo Sviluppo dell'Energia Nucleare e delle Energie Alternative, ENEA, to assess the indoor exposure of the Italian population. The programme, which started in 1982, includes regional and local surveys in all the administrative districts and intensive investigations of factors which influence indoor radon levels. The survey is organized by statistical areas of sampling to obtain representative samples of houses. The definition of the areas takes into account basic parameters e.g. geolithological environments, radon soil gas from underlying soils and rocks, specific activities of local building materials, climatic and seasonal variations, building technology, types of houses and town planning. The collected data may also be used for the compilation of radon risk maps to plan special monitoring and remedial actions if needed. Preliminary results concerning the above items are discussed.     

Risk assessment for indoor exposure to radon daughters

Approaches to and results for the estimation of healths risks from indoor exposure to radon and its daughter products are discussed. Particular weight is given to the derivation of exposure-time-effect relationships using a modified proportional hazard model which has been adapted to account for relevant epidemiological data.The results of this analysis indicate that about (10±5) % of the lung cancer rate observed in the general public might be correlated to the enhanced exposure to radon daughters in dwellings(at 10 – 20 Bq/m³ (Rn-eq)) and in outdoor air. A chronic exposure to indoor Rn-levels at home of about 300 – 500 Bq/m³ (Rn-eq) might possibly double the normal lung cancer rates. The relative fractions of radiogenic lung cancer rates might be nearly the same for smokers and non-smokers, and for men and women.     

Main sources of indoor radon in the swiss central Alps

To estimate the amount of radon gas transferred from the water to the indoor atmosphere of dwellings in the Swiss Central Alps, the radon concentrations of tap water of about 50 public water supplies were analysed. The radon levels of water in alpine communities fit a lognormal distribution with a geometric mean of 26.5 bq/1 and a geometric standard deviation of 3.15.Radon monitoring in typical homes in the Swiss Midland revealed a significant influence of wind velocity and temperature difference indoor/outdoor on the indoor radon-daughter levels during the winter period.     

Soil gas measurements below foundation depth improve indoor radon prediction

A soil gas measurement method developed earlier, [Nucl Tracks Radiat Meas, 22(1-4) (1993) 468] was applied to boreholes drilled to below foundation depth. Radon concentration and permeability were measured at 50-cm intervals. In radon prone areas, permeability showed an increase with depth over several orders of magnitude, indicating a low permeability top layer with a thickness of 0.5 m and more. A radon availability index (RAI) was empirically defined and the maximum RAI of each boring proved to be a reliable indicator for radon problems in nearby houses. The permeability of the top layer also proved to be an important factor for a better understanding of soil gas transport and the influence of rain. Implications for radon mitigation are derived.