scholarly journals Efficiency of the chimney effect controlling radon levels indoor

2019 ◽  
Vol 282 ◽  
pp. 02029
Author(s):  
Britt Haker Høegh ◽  
Torben Valdbjørn Rasmussen

According to the WHO the radioactive gas radon must be controlled indoors. E.g. by naturally driven suction systems based on thermal buoyancy, also denoted the chimney effect, which exploits the difference of indoor- and outdoor temperature to lower radon levels indoor. This paper presents four case studies showing that the efficiency of such systems to control radon level indoors varies, as the outdoor temperature varies throughout the year. The chimney effect was the driving force in the four single-family houses used as case studies. In two cases it was used to increase the indoor air change rate to dilute the radon concentration indoor, in one case it was used to drive a suction system under the ground slab to prevent radon from infiltrating through the ground slab, and in one case both techniques were used in combination. Measurements showed a correlation between a low radon level indoors and an increased difference between the indoor- and outdoor temperature, with the highest temperature indoor. Likely, the temperature difference can provide the needed suction in such systems. Without this driving force – out of the heating season – an increase of the indoor radon level was seen to occur. The needed suction to lower the radon level indoor did not occur in all cases. However, the efficiency of the system was seen to vary throughout the year, and was limited in periods with little difference between the indoor- and the outdoor temperature. Such needs to be taken into account, when the effect of naturally driven suction systems to reduce the radon level indoor are evaluated.

2021 ◽  
Vol 13 (4) ◽  
pp. 640
Author(s):  
Sadroddin Alavipanah ◽  
Dagmar Haase ◽  
Mohsen Makki ◽  
Mir Muhammad Nizamani ◽  
Salman Qureshi

The changing climate has introduced new and unique challenges and threats to humans and their environment. Urban dwellers in particular have suffered from increased levels of heat stress, and the situation is predicted to continue to worsen in the future. Attention toward urban climate change adaptation has increased more than ever before, but previous studies have focused on indoor and outdoor temperature patterns separately. The objective of this research is to assess the indoor and outdoor temperature patterns of different urban settlements. Remote sensing data, together with air temperature data collected with temperature data loggers, were used to analyze land surface temperature (outdoor temperature) and air temperature (indoor temperature). A hot and cold spot analysis was performed to identify the statistically significant clusters of high and low temperature data. The results showed a distinct temperature pattern across different residential units. Districts with dense urban settlements show a warmer outdoor temperature than do more sparsely developed districts. Dense urban settlements show cooler indoor temperatures during the day and night, while newly built districts show cooler outdoor temperatures during the warm season. Understanding indoor and outdoor temperature patterns simultaneously could help to better identify districts that are vulnerable to heat stress in each city. Recognizing vulnerable districts could minimize the impact of heat stress on inhabitants.


2003 ◽  
Vol 54 (1-2) ◽  
pp. 105-114
Author(s):  
Sukuman Sarikavanij ◽  
Montip Tiensuw

In this paper we discuss two case studies which clearly indicate the advantages of using a ranked set sample (RSS) over those of a simple random sample (SRS). The applications of RSS considered here cover single family homes sales data, and tree data. It is demonstrated that in each case RSS is much more efficient than SRS for estimation of population mean.


Purpose – This paper aims to review the latest management developments across the globe and pinpoint practical implications from cutting-edge research and case studies. Design/methodology/approach – This briefing is prepared by an independent writer who adds their own impartial comments and places the articles in context. Findings – Cooking is big business right now. Television cooking shows are highly popular and this in turn is generating interest in cooking as a pastime. As a result, many professional chefs are becoming celebrities, endorsing products and publishing books. Less obvious is their role as the leader of a team and the driving force behind the development of apprentice chefs. They set the pace and direction of learning in the kitchen and have an important role as a coach and facilitator. Practical implications – The paper provides strategic insights and practical thinking that have influenced some of the world’s leading organizations. Originality/value – The briefing saves busy executives and researchers hours of reading time by selecting only the very best, most pertinent information and presenting it in a condensed and easy-to-digest format.


Author(s):  
Eny Nor Syahira Mohamad Hashim ◽  
◽  
Norhafizah Salleh ◽  
Noor Azlina Abdul Hamid ◽  
◽  
...  

This paper proposes a cooling house system that can promote thermal comfort in buildings without air-conditioning. The cooling panel wall forms a part of an Integrated Building System (IBS), and is essentially made of tubes filled with either water or glycerin as the coolant. Target strength for the panel wall was designed based on the Malaysian Standard (MS) while the building ventilation system followed the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) standard. The results are reported based on indoor and outdoor temperature difference together with relative humidity to identify the best performing house model and also coolant. The outcome of this research is expected to add value to design concepts with a better promotion of air flow and circulation in the building, without over-usage of natural resources and higher building cost to achieve the same objective.


2008 ◽  
Vol 5 (4) ◽  
pp. 605-611
Author(s):  
Baghdad Science Journal

The present work aims to investigate approaches, measures and detection of indoor radon level in buildings of the department of physics in college of science of Baghdad University. CR-39 solid state nuclear track detectors were used to measure the radon concentrations inside the rooms, including five laboratories and five workplace rooms in ground and first storey of the department. The average radon concentration at first storey was found to be 43.1±13.2 Bq/m3 and 40.1±13.4 Bq/m3 at the ground storey. The highest level of radon concentration at the first storey in the radioactive sources store was 87.5±29 Bq/m3 while at the ground storey in room(2) was 70.2±24 Bq/m3 which is due to the existence radioactive sources in some selected places at the buildings.


2021 ◽  
Vol 19 (4) ◽  
pp. 921-941
Author(s):  
Yanrong Wang ◽  
Qizhi Wu ◽  
Xiang Zhang ◽  
Xiangbing Qiao

Agricultural industrialization consortium is a key policy tool to promote agricultural development for local governments in China. However, a stylized fact is that various consortia showed promising organizational performance at start, but then the performance deteriorated at later stages. The driving force behind is the dual paradox inherent in development and institution. The consortium is overly development oriented; yet as an institution it cannot adapt to the strong development impulses. Case studies show that the dual paradox inevitably led to the decline in organizational performance.


Author(s):  
Francesco Maggio ◽  
Starlight Vattano

For twenty years, the architecture of Italian rationalism through the digital modelling has been investigated. Very often, the production of a model and the consequent representation of tridimensional views, in many case studies, as outcome of the research on architecture have been considered. Actually, the digital model, intended as a critical tool, has to be conceived as a ‘starting point' for graphic analysis of architecture and not as the outcome. Indeed, it is associated to other graphics, sometimes not ‘deducted' from the model, useful for the understanding/translation of architecture. The construction of the model is not the construction of a simple image, operation, which is often carried out for the representation of the project, but it is the hermeneutic and critical result of the drawing tending to the analysis of the form, which is the true object of ‘imitation'. This study wants to contribute to the construction of a digital archive on the topic of the single-family house investigated by Piero Bottoni and Luigi Vietti.


2020 ◽  
Vol 191 (2) ◽  
pp. 219-222
Author(s):  
Tatiana Petrova ◽  
Petr Miklyaev

Abstract Continuous indoor radon measurements were carried out in two traditional Russian rural houses located in different villages of the Moscow region in summer of 2017 and 2018. In additional, in the summer of 2017, continuous measurements of soil gas radon activity concentration at depth 0.8 m and radon exhalation rate from the ground surface near the house were performed simultaneously. It was found that the indoor radon concentration in rural houses is subject to strong daily variations, which are characterized by highs at night and lows during the day. Indoor radon concentration is directly proportional to indoor and outdoor temperature difference and inversely proportional to wind speed. While the radon exhalation rate from the ground surface, as well as the ventilation of premises (opening doors and windows) practically do not affect the concentration of radon in Russian rural wooden houses.


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