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Journal articles on the topic 'Swimming pools – Water-supply'
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1
Mancic, Marko, Dragoljub Zivkovic, Pedja Milosavljevic, and Milena Todorovic. "Mathematical modelling and simulation of the thermal performance of a solar heated indoor swimming pool." Thermal Science 18, no. 3 (2014): 999–1010. http://dx.doi.org/10.2298/tsci1403999m.
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Buildings with indoor swimming pools have a large energy footprint. The source of major energy loss is the swimming pool hall where air humidity is increased by evaporation from the pool water surface. This increases energy consumption for heating and ventilation of the pool hall, fresh water supply loss and heat demand for pool water heating. In this paper, a mathematical model of the swimming pool was made to assess energy demands of an indoor swimming pool building. The mathematical model of the swimming pool is used with the created multi-zone building model in TRNSYS software to determine pool hall energy demand and pool losses. Energy loss for pool water and pool hall heating and ventilation are analyzed for different target pool water and air temperatures. The simulation showed that pool water heating accounts for around 22%, whereas heating and ventilation of the pool hall for around 60% of the total pool hall heat demand. With a change of preset controller air and water temperatures in simulations, evaporation loss was in the range 46-54% of the total pool losses. A solar thermal sanitary hot water system was modelled and simulated to analyze it's potential for energy savings of the presented demand side model. The simulation showed that up to 87% of water heating demands could be met by the solar thermal system, while avoiding stagnation.
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Kopp, Jan, Jindřich Frajer, and Marie Novotná. "New type of ponds? Changing of quantity and function of water bodies in rural built-up areas (Pilsen Region, Czechia)." European Countryside 9, no. 1 (March 1, 2017): 145–62. http://dx.doi.org/10.1515/euco-2017-0009.
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Abstract This study is focused on the changing of areas of water bodies in selected villages of the Pilsen Region (Czechia). We researched several different types of rural settlements and three time horizons with the help of old maps, orthophoto maps and GIS tools. To capture the influence of their location within the urban system, we chose 15 places from four categories (inner suburban area, outside suburban area, rural area, periphery rural area) depending on their distance to the core of the Pilsen agglomeration. There is no significant change in the amount of water bodies between the first reference period (1838-1839) and the second period (1957-1963) in the selected settlements. However, the third period (2013-2015) is characterized by the emergence of a large number of small water bodies - swimming pools and garden ponds. Based on the results of our research we identified the declining importance of public water bodies in some of the settlements. However, we have identified a notable prevalence of garden ponds which have a more positive ecological impact than pools. The proportion of private water bodies (covered and uncovered pools and garden ponds) in the total area of water bodies in the rural settlements in most cases is less than 20%, in the suburban settlements up to 100%. Peripheral settlements have a below-average share of these water bodies. The difference between the number of pools in different settlements is related to the proportion of newly built houses there. Although there are relatively fewer pools in rural settlements, the difference compared to the situation in suburban settlements is not pronounced due to the change in lifestyle in rural areas and the change in functions of some villages to recreational areas. Influence of pools on water consumption is dependent on the individual exchange technology of water in swimming pools. Filling of the pool before the season can overload the capacity of the local water supply.
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BRIGGS, A. D. M., N. S. BOXALL, D. VAN SANTEN, R. M. CHALMERS, and N. D. McCARTHY. "Approaches to the detection of very small, common, and easily missed outbreaks that together contribute substantially to human Cryptosporidium infection." Epidemiology and Infection 142, no. 9 (April 2, 2014): 1869–76. http://dx.doi.org/10.1017/s0950268814000673.
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SUMMARYWater supply-associated cryptosporidiosis outbreaks have decreased in England since the application of risk reduction measures to public water supplies. We hypothesized that smaller outbreaks were occurring which could be better detected by enhanced surveillance. Rolling analysis of detailed questionnaire data was applied prospectively in a population of 2·2 million in the south of England in 2009 and 2010. Detection of spatiotemporal clusters using SaTScan was later undertaken retrospectively. Together these approaches identified eight outbreaks, compared to an expectation of less than one based on national surveillance data. These outbreaks were small and associated with swimming pool use or, less commonly, direct (e.g. petting-farm) contact with animals. These findings suggest that frequent small-scale transmission in swimming pools is an important contributor to disease burden. Identification of swimming pool-level risk factors may inform preventative measures. These findings and the approaches described may be applicable to many other populations and to some other diseases.
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Totaro, Michele, Orlando Vaselli, Barbara Nisi, Lorenzo Frendo, Jacopo Cabassi, Sara Profeti, Paola Valentini, Beatrice Casini, Gaetano Privitera, and Angelo Baggiani. "Assessment, control, and prevention of microbiological and chemical hazards in seasonal swimming pools of the Versilia district (Tuscany, central Italy)." Journal of Water and Health 17, no. 3 (April 2, 2019): 490–98. http://dx.doi.org/10.2166/wh.2019.208.
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Abstract Although in Europe the quality of swimming pools (SPs) is dictated by regulations, microbiological and chemical hazards are described in the literature. Environmental bacteria or toxic disinfection by-product (DBP) compounds may indeed be recovered in waters even after disinfection. We evaluated the water quality from 26 outdoor seasonal SPs of the Versilia district, according to requirements of Regional Decree 54R/2015. In spring 2017, supply and reinstatement waters were collected after shock hyperchlorination (10 mg/L) while in summertime, a second sampling of waters before entering the pools, as well as in the pools, was performed after SPs were open to the public. In all samples, microbiological and chemical parameters were determined as defined by Directive 98/83/EC and the Italian Health Ministry. Microbiological data were within suggested limits. The first chemical analyses showed that in 35% of the feeding-pool seawater samples, the halogenated organic compounds were higher than the maximum permissible concentrations (30 μg/L). Pool waters were then dechlorinated and re-treated with hydrogen peroxide (10 mg/L) to ensure the abatement of DBPs (from 164 ± 107 to 0.9 ± 0.8 μg/L; p = 0.002). Results highlighted the need of self-controlled procedures for the SPs waters to prevent waterborne diseases and suggested hydrogen peroxide as the most appropriate disinfection method.
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FURTADO, C., G. K. ADAK, J. M. STUART, P. G. WALL, H. S. EVANS, and D. P. CASEMORE. "Outbreaks of waterborne infectious intestinal disease in England and Wales, 1992–5." Epidemiology and Infection 121, no. 1 (August 1998): 109–19. http://dx.doi.org/10.1017/s0950268898001083.
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Following the introduction of an improved surveillance system for infectious intestinal disease outbreaks in England and Wales, the Public Health Laboratory Service Communicable Disease Surveillance Centre received reports of 26 outbreaks between 1 January 1992 and 31 December 1995 in which there was evidence for waterborne transmission of infection. In these 26 outbreaks, 1756 laboratory confirmed cases were identified of whom 69 (4%) were admitted to hospital. In 19 outbreaks, illness was associated with the consumption of drinking water from public supplies (10 outbreaks) or private supplies (9 outbreaks). The largest outbreak consisted of 575 cases. In 4 of the remaining 7 outbreaks, illness was associated with exposure to swimming pool water. Cryptosporidium was identified as the probable causative organism in all 14 outbreaks associated with public water supplies and swimming pools. Campylobacter was responsible for most outbreaks associated with private water supplies. This review confirms a continuing risk of cryptosporidiosis from chlorinated water supplies in England and Wales, and reinforces governmental advice to water utilities that water treatment processes should be rigorously applied to ensure effective particle removal. High standards of surveillance are important for prompt recognition of outbreaks and institution of control measures. As microbiological evidence of water contamination may be absent or insufficient to implicate a particular water supply, a high standard of epidemiological investigation is recommended in all outbreaks of suspected waterborne disease.
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Arakelyan, R. S., and G. L. Shendo. "Sanitary and parasitological state of water bodites in the Аstrakhan region." Bulletin of the Russian Military Medical Academy 22, no. 4 (December 15, 2020): 168–71. http://dx.doi.org/10.17816/brmma62824.
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The article analyzes the sanitary and parasitological state of water bodies in the Astrakhan region in 20152019. A total of 16683 laboratory studies of water samples were conducted during the analyzed period. The number of samples taken from various environmental objects was 15253 (91,4%), of which 2595 (17%) were water samples taken from various water bodies. Of the last 82 (3,2%), samples did not meet sanitary standards. Centralized water supply was tested for parasitic contamination in 666 (25,7%) samples, swimming pool water in 947 (36,5%) samples, open water (river water) in 696 (26,8%) and wastewater in 286 (11%) samples. Of the 635 (24,5%) water samples collected in 2015, 14 (2,2%) did not meet hygiene standards. Of the 671 (25,9%) samples taken in 2016, 32 (4,8%) samples showed positive findings. Percentage of water samples collected and examined in 2017 it accounted for 463 (17,8%) of all water samples studied during the analyzed period, of which 14 (3%) did not meet sanitary standards. The share of water samples selected and tested for parasitic indicators in 2018 was 518 (22,4%), of which 18 (3,5%) samples did not meet the hygiene standards. In 2019, compared to previous years, the number of water samples taken for parasitic indicators decreased several times and amounted to 308 (11,9%), of which positive findings were noted in 4 (1,3%) samples. The absence of positive findings in water samples taken from Central water supply facilities indicates high-quality filtration and prevention of these facilities. The presence of cysts of pathogenic intestinal protozoa, as well as eggs and larvae of helminths in water samples taken from swimming pools and open reservoirs indicates fecal contamination of these objects. The presence of positive findings in wastewater samples indicates that sewage treatment plants do not provide reliable deworming and disinfection of wastewater.
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Marciano-Cabral, Francine, Rebecca MacLean, Alex Mensah, and Laurie LaPat-Polasko. "Identification of Naegleria fowleri in Domestic Water Sources by Nested PCR." Applied and Environmental Microbiology 69, no. 10 (October 2003): 5864–69. http://dx.doi.org/10.1128/aem.69.10.5864-5869.2003.
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ABSTRACT The free-living amoeboflagellate Naegleria fowleri is the causative agent of primary amoebic meningoencephalitis (PAM), a rapidly fatal disease of the central nervous system. In the United States, the disease is generally acquired while swimming and diving in freshwater lakes and ponds. In addition to swimming, exposure to N. fowleri and the associated disease can occur by total submersion in bathwater or small backyard wading pools. In the present study, swipe samples and residual pipe water from homes in Arizona were examined for N. fowleri by nested PCR due to the death of two previously healthy children from PAM. Since neither child had a history of swimming in a freshwater lake or pond prior to the onset of disease symptoms, the domestic water supply was the suspected source of infection. Of 19 samples collected from bathroom and kitchen pipes and sink traps, 17 samples were positive for N. fowleri by PCR. A sample from a Micro-Wynd II filter was obtained by passing water from bathtubs through the filter. Organisms attached to the filter also tested positive by PCR. The two samples that tested negative for N. fowleri were one that was obtained from a kitchen sink trap and a swipe sample from the garbage disposal of one home.
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Pulido, Manuel, Jesús Barrena-González, Alberto Alfonso-Torreño, Rafael Robina-Ramírez, and Saskia Keesstra. "The Problem of Water Use in Rural Areas of Southwestern Spain: A Local Perspective." Water 11, no. 6 (June 25, 2019): 1311. http://dx.doi.org/10.3390/w11061311.
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Water is a key strategic resource, particularly in Mediterranean climate-type areas with impermeable rocks and shallow soils like Southwestern Spain. The region of Extremadura is commonly known by its large surface occupied by big dams (30% of water dammed in Spain) although this theoretical abundance of water does not hide other problems of use. In this study, we have interviewed 132 people from the municipality of Arroyo de San Serván in order to know what the problems related to water use are, especially those that concern local people the most. Regarding the use of water at home, 90% of interviewees spend less than 60 EUR per month for water and their mean degree of satisfaction about the service is 3.7 out of 7. The reason for this low value can be the excessive content of calcium and bad taste according to 82.1%. Therefore, 64.2% of people do not usually drink water from the tap. Around two thirds of these local people usually buy water in the supermarket or drink filtered water. Concerning agricultural activities, local people gave great importance to irrigation as a source of employment (5.6/7) and inputs (4.5/7), although their satisfaction decreases about the current price of water for agriculture (0.02 EUR m−3). In addition, they are really worried about the overuse of fertilizers and herbicides (5.4/7) and they think about the necessity of taking measures to reduce these problems (6.1/7) as well as to reduce some management problems such as supply cuts. In the last few years, private (swimming pools) and public leisure facilities (swimming pool and spa) have been built in spite of not being considered important by local people (3.6–4.0/7). Nevertheless, about 60% of them consider these common facilities very positive in terms of employment, tourism attractions and entertainment for local people.
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Altayeva, F. A. "Growing commodity tilapia in various experimental conditions." Rybovodstvo i rybnoe hozjajstvo (Fish Breeding and Fisheries), no. 10 (October 1, 2020): 26–36. http://dx.doi.org/10.33920/sel-09-2010-03.
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The article presents the results of growing tilapia to marketable weight in experimental sites (Chilikskoye pond pond farms LLP, KATU named after S. Seifullin JSC and Kapshagai spawning farm — 1973 LLP). In the process of carrying out research works, the methods generally accepted in fish farming, hydrochemistry, hydrobiology, hydrology, ichthyology, as well as foreign normative and technical guidelines and methodological instructions on the technology of growing commercial tilapia in industrial conditions were used. Monitoring of hydrochemical analyses of water in ponds, swimming pools, and closed water supply installations is given. Fish-breeding and biological indicators of tilapia grown in various experimental conditions are presented. The results of the studies have shown the real possibility of growing tilapia in various conditions of fish farms in Kazakhstan. Based on the results of the work, the following conclusions were made: — satisfactory fish-breeding indicators were obtained with various cultivation technologies (as when growing tilapia in polyculture and monoculture in ponds, in pools, as well as cultivation in the recirculation system); — the cultivation of tilapia in the experimental ponds of the fish farm of the Almaty region of the Republic of Kazakhstan has shown the possibility of obtaining high fish-breeding biological indicators of tilapia and the ability to grow to marketable mass in a short time; — as a result of experimental cultivation in various conditions, it was found that the survival rate was not lower than 97%; — as a result of the analysis of the profitability indices of the developed technologies, it was found that the most profitable was the technology of growing marketable tilapia products in monoculture ponds on water with a natural thermal regime in Chilik Pond Economy LLP.
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Arakelyan, Rudolf S., Gennadiy L. Shendo, Viktoria A. Irdeeva, Tatyana M. Deeva, and Elizaveta V. Galkina. "Sanitary and parasitologic state of environmental objects. Analysis of work of the center for hy-giene and epidemiology in astrakhan region for 2015–2019." Perm Medical Journal 38, no. 1 (April 22, 2021): 115–22. http://dx.doi.org/10.17816/pmj381115-122.
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Objective. To study the sanitary and parasitologic state of environmental objects in Astrakhan Region for 20152019 at the example of studying the samples of soil, water and solid surface washes.
Materials and methods. Over the period from 2015 to 2019, at the laboratory departments of The Center for Hygiene and Epidemiology in Astrakhan Region, 15253 samples from different environmental objects were taken, 21850 studies were carried out. The number of samples, which did not satisfy the hygienic norms, was 2.5 % (383 samples).
Results. For the analyzed period, 4002 samples (26.2 %) of soil from the territory of Astrakhan and Astrakhan Region were taken and studied; 8004 investigations were performed. The number of samples, which did not satisfy the hygienic standards, was 7.5 % (300 samples). The number of samples of the washes from the solid surfaces was 56.7 % (8656 samples). Unsatisfactory samples made up 0.01 % (1 sample) in this sample, teniid oncospheres were detected (2019). The study of water samples taken from different water objects formed 17.0 % (2595 samples) out of the number of all sanitary and parasitologic studies carried out in 20152019. Water was taken from different sources of water supply including centralized water supply, water from swimming pools, water from open reservoirs and wastewater.
Conclusions. The presence of moving larvae of palisade worms and toxocar eggs in the soil confirms the infested animal fecal contamination of this object, and the presence of ascarid, opisthorchis, Hymenolepis nana, teniid oncospheres eggs and dysentery amoeba cysts in the soil the infested human fecal contamination. The presence of teniid oncospheres in the solid indoor washes demonstrates the contact of the infested person with this object. The presence of helminth eggs and larvae, typical for animals and human being in the samples taken from the open reservoirs indicates, first of all, contamination of these objects by feces of infested human beings and/or animals as well as the supposed version of water contamination by wastewater. The presence of eggs and larvae of helminths in the wastewater, dangerous for animals and human beings, testifies to a low-quality work of treatment facilities.
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Ferrández, Daniel, Carlos Moron, Jorge Pablo Díaz, and Pablo Saiz. "Aplicaciones del Captador Solar de Placa Plana y del Captador de Tubo de Vacío en la Edificación = Applications of the Flat Plate Solar Collectors and the Vacuum Tube Solar Collectors in Building." Anales de Edificación 4, no. 3 (September 15, 2018): 25. http://dx.doi.org/10.20868/ade.2018.3797.
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ResumenEl actual Código Técnico de la Edificación (CTE) pone de manifiesto la necesidad de cubrir parte de la demanda energética requerida para el abastecimiento de agua caliente sanitaria y climatización de piscinas cubiertas mediante sistemas de aprovechamiento de la energía solar térmica. En este artículo se presenta una comparativa entre las dos principales tipologías de captadores solares térmicos que existen en el mercado: el captador de placa plana y el captador de tubo de vacío, atendiendo a criterios de fracción solar, diseño e integración arquitectónica. Todo ello a fin de discernir en qué circunstancias es más favorable el uso de uno u otro sistema, comparando los resultados obtenidos mediante programas de simulación con la toma de medidas in situ.AbstractThe current Technical Building Code (CTE) highlights the need to cover part of the energy demand required for the supply of hot water and heating of indoor swimming pools using solar thermal systems. This article presents a comparison between the two main types of solar thermal collectors that exist in the market: the flat plate solar collector and the vacuum tube solar collector, according to criteria of solar fraction, design and architectural integration. All of this in order to discern in what circumstances the use of one or the other system is more favourable, comparing the results obtained through simulation programs with the taking of measurements in situ.
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Diniş, C. M., G. N. Popa, and A. Iagăr. "Automation of water supply and recirculation-filtration of water at a swimming pool using Zelio PLC." IOP Conference Series: Materials Science and Engineering 294 (January 2018): 012052. http://dx.doi.org/10.1088/1757-899x/294/1/012052.
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López, R., M. Vaca, H. Terres, A. Lizardi, J. Morales, and S. Chávez. "Experimental evaluation of a heat pump for the water-supply heating of a public swimming pool." Journal of Physics: Conference Series 792 (January 2017): 012020. http://dx.doi.org/10.1088/1742-6596/792/1/012020.
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Sousa, Ana, Pedro Figueiredo, David Pendergast, Per-Ludvik Kjendlie, João P. Vilas-Boas, and Ricardo J. Fernandes. "Critical Evaluation of Oxygen-Uptake Assessment in Swimming." International Journal of Sports Physiology and Performance 9, no. 2 (March 2014): 190–202. http://dx.doi.org/10.1123/ijspp.2013-0374.
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Swimming has become an important area of sport science research since the 1970s, with the bioenergetic factors assuming a fundamental performance-influencing role. The purpose of this study was to conduct a critical evaluation of the literature concerning oxygen-uptake (VO2) assessment in swimming, by describing the equipment and methods used and emphasizing the recent works conducted in ecological conditions. Particularly in swimming, due to the inherent technical constraints imposed by swimming in a water environment, assessment of VO2max was not accomplished until the 1960s. Later, the development of automated portable measurement devices allowed VO2max to be assessed more easily, even in ecological swimming conditions, but few studies have been conducted in swimming-pool conditions with portable breath-by-breath telemetric systems. An inverse relationship exists between the velocity corresponding to VO2max and the time a swimmer can sustain it at this velocity. The energy cost of swimming varies according to its association with velocity variability. As, in the end, the supply of oxygen (whose limitation may be due to central—O2 delivery and transportation to the working muscles—or peripheral factors—O2 diffusion and utilization in the muscles) is one of the critical factors that determine swimming performance, VO2 kinetics and its maximal values are critical in understanding swimmers’ behavior in competition and to develop efficient training programs.
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CHALMERS, R. M., R. SMITH, K. ELWIN, F. A. CLIFTON-HADLEY, and M. GILES. "Epidemiology of anthroponotic and zoonotic human cryptosporidiosis in England and Wales, 2004–2006." Epidemiology and Infection 139, no. 5 (July 12, 2010): 700–712. http://dx.doi.org/10.1017/s0950268810001688.
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SUMMARYIn order to monitor epidemiological trends, Cryptosporidium-positive samples (n=4509) from diarrhoeic patients were typed. Compared to the previous 4 years, the proportion of Cryptosporidium hominis cases in 2004–2006 increased to 57·3%, while 38·5% were C. parvum. The remaining 4·2% cases included mixed C. parvum and C. hominis infections, C. meleagridis, C. felis, C. ubiquitum and a novel genotype. When the typing results were combined with enhanced surveillance data to monitor risk exposures, C. hominis was linked to urban dwelling, previous diarrhoea in the household, any travel especially abroad, and using a swimming or paddling pool. C. parvum was linked to having a private water supply, contact with surface water, visiting or living on a farm, and contact with farm animal faeces. The proportion of laboratory-confirmed indigenous cases acquired from direct contact with farm animals was estimated to be 25% for C. parvum and 10% of all reported Cryptosporidium cases.
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"Fire-Related Aspects." Earthquake Spectra 11, no. 2_suppl (April 1995): 419–35. http://dx.doi.org/10.1193/1.1585853.
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The Northridge earthquake caused high shaking intensities for several million persons in the northern Los Angeles region, centered in the San Fernando Valley. Fire protection for the heavily damaged area is furnished primarily by Los Angeles City Fire Department and, to a lesser extent, Los Angeles County, Santa Monica, and other departments. The earthquake resulted in about 110 fires, about 80% of which were structure fires. Of these, most were in single-or multi-family dwellings. All of the initial fires were out before noon despite impaired communications, wide-scale failure of firefighting water supply in large parts of the San Fernando Valley, and other problems. Alternative water supplies, such as backyard swimming pools, were employed in some cases. Mutual aid was requested by fire departments in the affected area, but resources from outside the Los Angeles metropolitan area were not required.
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Almutairi, Khalid, Ali Mostafaeipour, Negin Baghaei, Kuaanan Techato, Shahariar Chowdhury, Mehdi Jahangiri, Mostafa Rezaei, Seyyed Jalaladdin Hosseini Dehshiri, Hossein Goudarzi, and Alibek Issakhov. "Techno-Economic Investigation of Using Solar Energy for Heating Swimming Pools in Buildings and Producing Hydrogen: A Case Study." Frontiers in Energy Research 9 (May 19, 2021). http://dx.doi.org/10.3389/fenrg.2021.680103.
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Solar energy is a free and environmentally friendly supply of power that has negligible impact on the environment, and it has long been used by humans through different methods. However, solar energy technology would use for heating water for buildings as an alternative resource, which would help reduce CO2 reduction and safe environment. A data analysis was performed using the RETScreen software, and the financial outcomes that were calculated using two methods. Clearly, the software is operational with two different methods. Both methods indicate that this project is economically feasible. The aim of this study is to evaluate the utilization of solar energy for household and commercial purposes. The first goal is to explore the technical, economic, and environmental aspects of using evacuated glass tube solar collectors to heat water in an indoor pool in the building, having an area of 50 m2, in the city of Yazd, Iran. The second goal is to evaluate the amount of hydrogen that can be obtained from the installation photovoltaic systems in the province. The results also show that this project will decrease greenhouse gas emissions by 142 ton-CO2 over 20 years of the useful life of a collector, thereby indicating the possible significant role of such collectors in the reduction of greenhouse gas emissions. Furthermore, the findings indicate that installing a single X21-345 photovoltaic system with a performance rate of 20% can result in the production of 2.1 kg of hydrogen annually.