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1.
Environ Sci Pollut Res Int ; 31(12): 18672-18682, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38349494

RESUMO

Decoupling cooling and ventilation tasks with an existing air conditioning methodology are a promising performance-enhancement technology. In this direction, different configurations of a desiccant-integrated independent ventilation element attached to a conventional cooling system are proposed in this study. This work establishes a quantitative comparative performance analysis among the different process air cooling (obtained through desiccant dehumidification) techniques for three different climates, namely, hot-dry, tropical, and Mediterranean. EnergyPlus simulations have been executed on a small-scale office building of 400-m2 area. The building constructional details and other required simulation input parameters follow benchmark standards. As the chemical dehumidification increases, the process air, i.e., supply air temperature that cannot be sent directly to the room, needs to be cooled. Three approaches for process air cooling have been considered: direct expansion (DX) cooling coil, indirect evaporative cooling (IEC), and sensible heat recovery wheel (SHRW). A solar collector assembly with a supporting heating arrangement is coupled with desiccant unit for regeneration. Outdoor air is used for regeneration in the case of the DX cooling coil and IEC, whereas return air is used in the heat recovery wheel case. Annual simulation results reveal that the SHRW-aided case performs superior than DX coil case for the pertinent climatic conditions, with 9.6 to 45.01% of annual energy savings. For the IEC, energy consumption was 1.8 to 18.38% less than that of DX coil. Also, using return air in this best-suited case reduces the net thermal energy requirement for regeneration by 14.63 to 71.65% with respect to DX coil.


Assuntos
Ar Condicionado , Energia Solar , Higroscópicos , Temperatura , Temperatura Alta
2.
Environ Pollut ; 345: 123550, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38355083

RESUMO

Due to the outbreak of COVID-19, an increased risk of airborne transmission has been experienced in buildings, particularly in confined public places. The need for ventilation as a means of infection prevention has become more pronounced given that some basic precautions (like wearing masks) are no longer mandatory. However, ventilating the space as a whole (e.g., using a unified ventilation rate) may lead to situations where there is either insufficient or excessive ventilation in localized areas, potentially resulting in localized virus accumulation or large energy consumption. It is of urgent need to investigate real-time control of ventilation systems based on local demands of the occupants to strike a balance between infection risk and energy saving. In this work, a zonal demand-controlled ventilation (ZDCV) strategy was proposed to optimize the ventilation rates in sub-zones. A camera-based occupant detection method was developed to detect occupants (with eight possible locations in sub-zones denoted as 'A' to 'H'). Linear ventilation model (LVM), dimension reduction, and artificial neural network (ANN) were integrated for rapid prediction of pollutant concentrations in sub-zones with the identified occupants and ventilation rates as inputs. Coordinated ventilation effects between sub-zones were optimized to improve infection prevention and energy savings. Results showed that rapid prediction models achieved an average prediction error of 6 ppm for CO2 concentration fields compared with the simulation under different occupant scenarios (i.e., occupant locations at ABH, ABCFH, and ABCDEFH). ZDCV largely reduced the infection risk to 2.8% while improved energy-saving efficiency by 34% compared with the system using constant ventilation rate. This work can contribute to the development of building environmental control systems in terms of pollutant removal, infection prevention, and energy sustainability.


Assuntos
Poluição do Ar em Ambientes Fechados , Poluentes Ambientais , Poluição do Ar em Ambientes Fechados/prevenção & controle , Poluição do Ar em Ambientes Fechados/análise , Ventilação , Ar Condicionado , Respiração
3.
Environ Sci Pollut Res Int ; 31(9): 14135-14155, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38270763

RESUMO

COVID-19 and other respiratory infectious viruses are highly contagious, and patients need to be treated in negative pressure wards. At present, many negative pressure wards use independent air conditioning equipment, but independent air conditioning equipment has problems such as indoor air circulation flow, condensate water accumulation, and improper filter maintenance, which increase the risk of infection for healthcare workers and patients. The radiation air conditioning system relies on the radiation ceiling to control the indoor temperature and uses new air to control the indoor humidity and air quality. The problems caused by the use of independent air conditioning equipment should be avoided. This paper studies the thermal comfort, contaminant distribution characteristics, contaminant removal efficiency, and accessibility of supply air in a negative pressure ward with a radiation air conditioning system under three airflow patterns. In addition, the negative pressure ward was divided into 12 areas, and the infection probability of healthcare workers in different areas was analyzed. The results show that the application of radiation air conditioning systems in negative pressure wards can ensure the thermal comfort of patients. Stratum ventilation and ceiling-attached jets have similar effects in protecting healthcare workers; both can effectively reduce the contaminant concentrations and the risk of infection of healthcare workers. Ceiling-attached jets decreases the contaminant concentrations by 10.73%, increases the contaminant removal efficiency by 12.50%, and decreases the infection probability of healthcare workers staying indoors for 10 min by 23.18%, compared with downward ventilation.


Assuntos
Poluição do Ar em Ambientes Fechados , Poluição do Ar , Humanos , Poluição do Ar em Ambientes Fechados/análise , Isoladores de Pacientes , Ar Condicionado , Temperatura , Ventilação/métodos
4.
Int J Biometeorol ; 68(2): 289-304, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38047941

RESUMO

Passenger thermal comfort in high-speed train (HST) carriages presents unique challenges due to factors such as extensive operational areas, longer travel durations, larger spaces, and higher passenger capacities. This study aims to propose a new prediction model to better understand and address thermal comfort in HST carriages. The proposed prediction model incorporates skin wettedness, vertical skin temperature difference (ΔTd), and skin temperature as parameters to predict the thermal sensation vote (TSV) of HST passengers. The experiments were conducted with 65 subjects, evenly distributed throughout the HST compartment. Thermal environmental conditions and physiological signals were measured to capture the subjects' thermal responses. The study also investigated regional and overall thermal sensations experienced by the subjects. Results revealed significant regional differences in skin temperature between upper and lower body parts. By analyzing data from 45 subjects, We analyzed the effect of 25 variables on TSV by partial least squares (PLS), from which we singled out 3 key factors. And the optimal multiple regression equation was derived to predict the TSV of HST occupants. Validation with an additional 20 subjects demonstrated a strong linear correlation (0.965) between the actual TSV and the predicted values, confirming the feasibility and accuracy of the developed prediction model. By integrating skin wettedness and ΔTd with skin temperature, the model provides a comprehensive approach to predicting thermal comfort in HST environments. This research contributes to advancing thermal comfort analysis in HST and offers valuable insights for optimizing HST system design and operation to meet passengers' comfort requirements.


Assuntos
Ar Condicionado , Temperatura Cutânea , Humanos , Ar Condicionado/métodos , Sensação Térmica/fisiologia , Temperatura
5.
Environ Pollut ; 343: 123164, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38103710

RESUMO

The Coronavirus disease 2019 (COVID-19) pandemic demonstrated the threat of airborne pathogenic respiratory viruses such as the airborne Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The ability to detect circulating viruses in a workplace or dormitory setting allows an early warning system that can alert occupants to implement precautions (e.g. masking) and/or trigger individual testing to allow isolation and quarantine measures to halt contagion. This work extends and validates the first successful detection of SARS-CoV-2 virus in dormitory Heating, Ventilation, and Air Conditioning (HVAC) systems and compares different air sampling methods and media types combined with optimized quantitative Reverse-Transcription PCR (qRT-PCR) analysis. The study was performed in two environments; large dormitories of students who underwent periodic testing for COVID-19 (unknown environment) and the HVAC air from a suite with a student who had tested positive for COVID-19 (known dorm). The air sampling methods were performed using Filter Cassettes, BioSampler, AerosolSense Sampler and Button Sampler (with four media types with different pore sizes of 5 µm, 3 µm, 3 µm (gelatin), and 1.2 µm). The SARS-CoV-2 positive air samples were compared with the positive samples collected by individual student campus track tracing methods using PCR testing on saliva and nasopharyngeal samples. The results show a detection rate of 73% in the unknown environment and a 78% detection rate in the known dorm. Our data show that the virus was detectable with all the sampling methods we employed. However, the AerosolSense sampler and BioSampler performed the best at 63% and 61% detection rates, compared to 25% for the Filter Cassettes and 23% for the Button Sampler. Despite the success rate, it is not possible to definitively conclude which method is most sensitive due to the limited number of samples. These results show that with careful sampling and optimized PCR methods, pathogenic respiratory viruses can be detected in large buildings using HVAC return air.


Assuntos
COVID-19 , Vírus , Humanos , SARS-CoV-2 , COVID-19/diagnóstico , Ar Condicionado , Calefação , Teste para COVID-19
6.
AORN J ; 119(1): 93-98, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38149900

RESUMO

Off-label medication use and prescribing practices Key words: off-label, licensed prescriber, approved, unapproved, US Food and Drug Administration (FDA). Prophylactic, therapeutic, and empiric use of antimicrobial agents Key words: prophylactic, therapeutic, empiric, infection, antimicrobial. Perioperative RN administration of antineoplastic agents Key words: antineoplastic medication, chemotherapy, hyperthermic intraperitoneal chemotherapy (HIPEC), instillation device, perfusionist. Minimum efficiency reporting values, parameters, and testing for air filters in heating, ventilation, and air-conditioning systems Key words: heating, ventilation, and air-conditioning (HVAC); minimum efficiency reporting value (MERV); particle size removal efficiency; air filter; filtration.


Assuntos
Ar Condicionado , Filtros de Ar , Estados Unidos , Filtração , Ventilação
7.
AORN J ; 119(1): 72-80, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38149898

RESUMO

Hospital construction and renovation is an ongoing occurrence in the health care setting. The recently updated AORN "Guideline for design and maintenance of the surgical suite" provides perioperative nurses with information on the layout design and maintenance of perioperative spaces; safety measures to use during construction and renovation; monitoring and maintenance of the heating, ventilation, and air conditioning; and how to respond to unintended utility failures. This article provides an overview of the guideline and discusses recommendations for the interdisciplinary team, planning and designing the surgical suite, construction-related environmental contamination, ORs, and OR maintenance. It also includes a scenario describing specific concerns associated with the construction of an additional OR. Perioperative nurses should review the guideline in its entirety and apply the recommendations when participating in perioperative construction and renovation projects.


Assuntos
Ar Condicionado , Ventilação , Humanos
8.
Neuroreport ; 35(1): 1-8, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37942702

RESUMO

The impressions of heating, ventilation, and air conditioning (HVAC) sounds are important for the comfort people experience in their living spaces. Revealing neural substrates of the impressions induced by HVAC sounds can help to develop neurophysiological indices of the comfort of HVAC sounds. There have been numerous studies on the brain activities associated with the pleasantness of sounds, but few on the brain activities associated with the thermal impressions of HVAC sounds. Seven time-varying HVAC sounds were synthesized as stimuli using amplitude modulation. Six participants took part in subjective evaluation tests and MEG measurements. Subjective coolness of the HVAC sounds was measured using the paired comparison method. Magnetoencephalographic (MEG) measurements were carried out while participants listened to and compared the time-varying HVAC sounds. Time-frequency analysis and cluster-based analysis were performed on the MEG data. The subjective evaluation tests showed that the subjective coolness of the amplitude-modulated HVAC sounds was affected by the modulation frequency, and that there was individual difference in subjective coolness. A cluster-based analysis of the MEG data revealed that the brain activities of two participants significantly differed when they listened to cooler or less cool HVAC sounds. The frontal low-theta (4-5 Hz) and the temporal alpha (8-13 Hz) activities were observed. The frontal low-theta and the temporal alpha activities may be associated with the coolness of HVAC sound. This result suggests that the comfort level of HVAC sound can be evaluated and individually designed using neurophysiological measurements.


Assuntos
Ar Condicionado , Calefação , Humanos , Análise por Pareamento , Som , Fenômenos Magnéticos , Estimulação Acústica
9.
Environ Sci Pollut Res Int ; 30(59): 123643-123656, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37991616

RESUMO

The global "copper-poor and aluminum-rich" situation has made the possibility of "copper saving with aluminum" an important topic. This study established a framework for analyzing multiple substances' coupled flows at the product level based on material flow analysis (MFA), and took the household air conditioning system of the Chinese mainland in 2020 as an example to characterize the coupled flows of aluminum and copper. The results showed that the system consumed 0.69 million tons of aluminum and 2.10 million tons of copper, and discharged 0.17 million tons of aluminum and 0.43 million tons of copper to the environment cumulatively to achieve 13.2 million terajoules of final heat exchanged and serve 1.24 billion square meters during lifetime in mainland China alone, secondary aluminum and copper accounted for only 22.61% and 24.83% of the total consumption, and the in-use stocks increased by 0.19 million tons of aluminum and 0.70 million tons of copper. The external dependency of copper ore was 92.83%, which was significantly higher than the 44.29% of bauxite. The comprehensive utilization efficiency of copper reached 77.88%, which was slightly higher than the 70.80% of aluminum. The conclusion indicates that under the premise of meeting use requirements, promoting "replacing copper with aluminum" can improve the stability and safety of China's material supply chain, but there is a need to further boost the production efficiency of aluminum in primary production.


Assuntos
Alumínio , Cobre , Alumínio/análise , Cobre/análise , Ar Condicionado , China , Óxido de Alumínio/análise
10.
Environ Int ; 181: 108310, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37951014

RESUMO

BACKGROUND: Air conditioning (AC) presents a viable means of tackling the ill-effects of heat on human health. However, AC releases additional anthropogenic heat outdoors, and this could be detrimental to human health, especially in urban communities. This study determined the excess heat-related mortality attributable to anthropogenic heat from AC use under various projected global warming scenarios in seven Japanese cities. The overall protection from AC use was also measured. METHODS: Daily average 2-meter temperatures in the hottest month of August from 2000 to 2010 were modeled using the Weather Research and Forecasting (WRF) model with BEP+BEM (building effect parameterization and building energy model). Risk functions for heat-mortality associations were generated with and without AC use from a two-stage time series analysis. We coupled simulated August temperatures and heat-mortality risk functions to estimate averted deaths and unavoidable deaths from AC use. RESULTS: Anthropogenic heat from AC use slightly augmented the daily urban temperatures by 0.046 °C in Augusts of 2000-2010 and up to 0.181 °C in a future with 3 °C urban warming. This temperature rise was attributable to 3.1-3.5 % of heat-related deaths in Augusts of 2000-2010 under various urban warming scenarios. About 36-47 % of heat-related deaths could be averted by air conditioning use under various urban warming scenarios. DISCUSSION: AC has a valuable protective effect from heat despite some unavoidable mortality from anthropogenic heat release. Overall, the use of AC as a major adaptive strategy requires careful consideration.


Assuntos
Ar Condicionado , Calor Extremo , Mortalidade , Humanos , Cidades , Japão
11.
Environ Sci Pollut Res Int ; 30(49): 108188-108200, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37749467

RESUMO

The main component of an air conditioning system is air filters. Over time, the filters of an air conditioning system in cars can turn into sources of emission of microbiological hazards. The aim of this study was to quantitatively and qualitatively assess the presence of infectious and toxic fungi in the AC filters in passenger cars. The studied non-woven filters were removed from passenger cars during the "winter"/"summer" seasons. The taxonomic identification of the fungi isolated from the filters was performed using both the culture-based and molecular methods. RT-PCR was applied to assess the presence of gene fragments regulating aflatoxin biosynthesis in the isolates obtained from fungal cultures. The average fungal concentrations in the filter samples collected during the summer/winter season were 5.4 × 104 cfu/m2 and 2.4 × 104 cfu/m2, respectively. Most of the filter samples, collected in both the studied seasons, revealed the presence of Aspergillus species including A. fumigatus, A. niger, A. terreus and/or A. flavus. The recorded levels of fungal contamination of AC filters in passenger cars indicate the necessity for more frequent filter replacement in this type of vehicle. Occupational exposure to moulds and the resulting health problems that may be experienced by professional drivers should be properly recognised in order to undertake effective preventive measures.


Assuntos
Filtros de Ar , Poluentes Ocupacionais do Ar , Poluição do Ar em Ambientes Fechados , Exposição Ocupacional , Automóveis , Poluentes Ocupacionais do Ar/análise , Ar Condicionado , Fungos , Exposição Ocupacional/análise , Microbiologia do Ar , Poluição do Ar em Ambientes Fechados/análise
12.
J Agric Food Chem ; 71(35): 12975-12985, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37625125

RESUMO

The allergen Mal d 1 is often responsible for adverse allergic reactions to fresh apples in northern and central Europe. The Mal d 1 content and isoallergen profile are proposed to have an impact on the allergenic potential of the fruit. Therefore, we investigated the impact of the cropping system on the Mal d 1 content and the isoallergen profile of apples by mass spectrometry for the varieties 'Jonagored' and 'Topaz'. To monitor the impact of storage time and conditions, apples of the varieties 'Santana' and 'Jonagold' were stored for up to 12 weeks under regular air (RA), under RA in combination with 1-methylcyclopropene (1-MCP) treatment, and under a controlled atmosphere (CA). The impact of the cropping system (integrated production vs organic production) was negligible. However, a significant increase in the Mal d 1 content during storage was observed, being higher when stored under CA conditions than under RA conditions. An additional treatment with 1-MCP prior to RA storage drastically reduced the level of Mal d 1 expression in the flesh of the apples by ∼50%. Furthermore, the content of isoallergens 1.03 and 1.06 increased disproportionately under CA conditions, while under RA conditions, only isoallergen 1.06 was affected. With the 1-MCP treatment, no changes in the isoallergen profile were obvious.


Assuntos
Malus , Frutas , Ar Condicionado , Clima
13.
J Hosp Infect ; 141: 33-40, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37640266

RESUMO

Guidelines for heating, ventilation, and air-conditioning systems have been developed for different settings. However, there is a lack of up-to-date evidence providing concrete recommendations for the heating, ventilation, and air-conditioning systems of an isolation room, which is essential to appropriately guide infection control policies. To highlight the guidelines for heating, ventilation, and air-conditioning systems in isolation rooms to inform relevant stakeholders and policymakers. A systematic search was performed based on Joanna Briggs Methodology using five databases (CINAHL, Embase, Joanna Briggs Institute, Medline, and Web of Science) and websites. Eight articles published by government departments were included in this review. Most studies recommended controlled airflow without recirculation, 12 air changes per hour, high-efficiency particulate air filtrate to exhaust contaminated air from the airborne isolation room, humidity ≤60%, and temperature in the range of 18-30 °C. This review provides further evidence that there is a need for interdisciplinary collaborative research to quantify the optimum range for heating, ventilation, and air conditioning system parameters, considering door types, anterooms, and bed management, to effectively reduce the transmission of infection in isolation rooms.


Assuntos
Poluição do Ar em Ambientes Fechados , Calefação , Humanos , Ventilação/métodos , Ar Condicionado , Fenômenos Fisiológicos Respiratórios , Atenção à Saúde
15.
Health Rep ; 34(7): 19-26, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37470464

RESUMO

Background: Household air conditioning is one of the most effective approaches for reducing the health impacts of heat exposure; however, few studies have measured the prevalence of household air conditioning in Canada. Data and methods: Data were obtained from the 2017 Canadian Community Health Survey and the 2017 Households and the Environment Survey. Statistics Canada linked the survey respondents and created survey weights. Four heat-vulnerable populations were defined: older adults, older adults living alone, older adults with at least one health condition associated with reduced thermoregulation and older adults living alone and with a health condition associated with reduced thermoregulation. Weighted ratios and logistic regression models were used to analyze person-level air conditioning rates for national, regional and heat-vulnerable populations. Results: Approximately 61% of the national population had household air conditioning. Regional rates ranged between 32% in British Columbia and 85% in Ontario. People living alone and people who did not own a home were significantly less likely to have air conditioning in Canada and in most regions. One heat vulnerable group, older adults living alone, had significantly lower air conditioning rates compared with the national and Ontario averages, at 56% and 81%, respectively. Interpretation: This study is the first to quantify air conditioning prevalence in Canada at the person-level. The results of this study may inform heat-health policies and climate change adaptation strategies that aim to identify populations with high risks of heat-related mortality or morbidity and low access to household air conditioning.


Assuntos
Ar Condicionado , Temperatura Alta , Humanos , Idoso , Canadá/epidemiologia , Prevalência , Saúde Pública , Ontário
16.
Sensors (Basel) ; 23(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37447806

RESUMO

Due to energy constraints and people's increasing requirements for indoor thermal comfort, improving energy efficiency while ensuring thermal comfort has become the focus of research in the design and operation of HVAC systems. This study took office rooms with few people occupying them in Wuhan as the research object. The EnergyPlus-Fluent co-simulation method was used to study the impact of 12 forms of air distribution on the thermal environment and air-conditioner energy consumption. The results indicate that 3 m/s supply air velocity and 45° supply air angle are more suitable for the case model in this study. The EnergyPlus-Fluent co-simulation method used in this paper provides a reference for the study of indoor environments in offices with few people occupying them.


Assuntos
Poluição do Ar em Ambientes Fechados , Fenômenos Fisiológicos , Humanos , Ar Condicionado/métodos , Simulação por Computador
17.
Int J Biometeorol ; 67(8): 1335-1344, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37347280

RESUMO

In this paper, the future prediction of predicted mean vote (PMV) index of indoor environment is studied. PMV is the evaluation index used in this paper to represent the thermal comfort of human body. According to the literature, the main environmental factors affecting PMV index are temperature, humidity, black globe temperature, wind speed, average radiation temperature, and clothing surface temperature, and there is a complex nonlinear relationship between the six variables. Due to the coupling relationship between the six parameters, the PMV formula can be simplified under specific conditions, reducing the monitoring of variables that are difficult to observe. Then, the improved grey system prediction model GM(1,1) with optimized selection dimension is used to predict the future time of PMV. Due to the irregularity, uncertainty and fluctuation of PMV values in time series, based on the original GM(1,1) time series prediction, an adaptive GM(1,1) improved model is proposed, which can continuously change with time series and enhance its prediction accuracy. By contrast, the improved GM(1,1) model can be derived from the sliding window of the adaptive model through changes in the dataset and get better model grades. It lays a foundation for the future research on the predicted index of PMV, so as to set and control the air conditioning system in advance, to meet the intelligence of modern intelligent home and humanized function of sensing human comfort.


Assuntos
Ar Condicionado , Vento , Humanos , Fatores de Tempo , Temperatura , Umidade
18.
Front Public Health ; 11: 1164817, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37361169

RESUMO

Introduction: Prolonged exposure of train drivers to thermal discomfort can lead to occupational safety and health (OSH) risks, causing physical and mental injuries. Traditional method of treating human skin as a wall surface fail to observe accurate skin temperature changes or obtain human thermal comfort that adapts to the thermal environment. Methods: This study employs the Stolwijk human thermal regulation model to investigate and optimize the thermal comfort of train drivers. To minimize the time-consuming design optimization, a pointer optimization algorithm based on radial basis function (RBF) approximation was utilized to optimize the train cab ventilation system design and enhance drivers' thermal comfort. The train driver thermal comfort model was developed using Star-CCM+ and 60 operating conditions were sampled using an Optimal Latin Hypercube Design (Opt LHD). Results and Discussion: We analyzed the effects of air supply temperature, air supply volume, air supply angle, solar radiation intensity and solar altitude angle on the local thermal sensation vote (LTSV) and overall thermal sensation vote (OTSV) of the train driver. Finally, the study obtained the optimal air supply parameters for the Heating Ventilation and Air Conditioning (HVAC) in the train cabin under extreme summer conditions, effectively improving the thermal comfort of the driver.


Assuntos
Ar Condicionado , Temperatura Cutânea , Humanos , Temperatura , Ar Condicionado/métodos , Calefação , Sensação Térmica
19.
Sci Rep ; 13(1): 10149, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37349368

RESUMO

A three-dimensional CFD simulation model was established to study the characteristics of flow, drifts and salt deposition from 6 super-large seawater cooling towers in a power station. In the model, site meteorological data, design parameters of cooling tower, general layout, environmental characteristics, are considered. The results show that: (1) when the wind direction is parallel to the towers, the streams overlap, reducing deposition of drifts and salt onto the ground. (2) The drifts with particle size greater than 550 µm cannot float out of cooling towers. (3) In normal operation of 6 such cooling towers, the resulting salt deposition will not cause serious damage to plants.


Assuntos
Ar Condicionado , Microbiologia da Água , Temperatura Baixa , Água do Mar , Rios
20.
HERD ; 16(4): 56-68, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37365804

RESUMO

AIM: Establish the influence of the terminal or nonterminal position of High Efficiency Particulate Air (HEPA) filters in the Heating, Ventilation, and Air Conditioning (HVAC) system on the presence of airborne fungi in controlled environment rooms. BACKGROUND: Fungal infections are an important cause of morbidity and mortality in hospitalized patients. METHODS: This study was realized from 2010 to 2017, in rooms with terminal and nonterminal HEPA filters, in eight Spanish hospitals. In rooms with terminal HEPA filters, 2,053 and 2,049 samples were recollected, and in rooms with nonterminal HEPA filters, 430 and 428 samples were recollected in the air discharge outlet (Point 1) and in the center of the room (Point 2), respectively. Temperature, relative humidity, air changes per hour, and differential pressure were recollected. RESULTS: Multivariable analysis showed higher odds ratio (OR) of airborne fungi presence when HEPA filters were in nonterminal position (OR: 6.78; 95% CI [3.77, 12.20]) in Point 1 and (OR: 4.43; 95% CI [2.65, 7.40]) in Point 2. Other parameters influenced airborne fungi presence, such as temperature (OR: 1.23; 95% CI [1.06, 1.41]) in Point 2 differential pressure (OR: 0.86; 95% CI [0.84, 0.90]) and (OR: 0.88; 95% CI [0.86, 0.91]) in Points 1 and 2, respectively. CONCLUSIONS: HEPA filter in terminal position of the HVAC system reduces the presence of airborne fungi. To decrease the presence of airborne fungi, adequate maintenance of the environmental and design parameters is necessary in addition to the terminal position of the HEPA filter.


Assuntos
Filtros de Ar , Poluição do Ar em Ambientes Fechados , Humanos , Filtros de Ar/microbiologia , Ar Condicionado , Calefação , Poluição do Ar em Ambientes Fechados/prevenção & controle , Poluição do Ar em Ambientes Fechados/análise , Ventilação , Poeira/análise , Fungos
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