scholarly journals Improving the indoor air quality (IAQ) in naturally ventilated lecture hall with a single facade by solar chimneys

2021 ◽  
Vol 68 (1) ◽  
Author(s):  
Ahmed Fikry ◽  
Asmaa Elsayed
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Cross Section ◽  
Indoor Air ◽  
Natural Ventilation ◽  
Indoor Air Pollution ◽  
Lecture Hall ◽  
Air Velocity ◽  
Cross Section Area ◽  
Section Area

AbstractIn this paper, the indoor air pollution was investigated inside an educational building which contains air pollutants with elevated concentrations. A field study was conducted in a naturally ventilated, single-faceted lecture’s hall to evaluate the indoor air quality (IAQ). Both air velocity and carbon dioxide (CO2) concentrations were measured at the respiratory area level to compare these values with ASHRAE standard (62.01-2019). The computational fluid dynamics (CFD) 3D model was utilized to predict the air velocity, and CO2 concentrations, and to validate the measured air concentrations. The measured results fairly agree with the numerical CFD data with a 6.2% difference between both values. This paper deals with experimental work to study the effect of the cross-section area, the number, and the height of the solar chimneys. The results showed that using solar chimneys improved the natural ventilation in the hall and minimized the CO2 concentrations. Additionally, using the chimney cross-section area of 0.25*0.25 m, 0.30*0.30 m, and 0.40*0.40 to 0.50*0.50 m can reduce the CO2 concentrations to (3%, 6.2%, 6.4%, and 6.7%, respectively). While using three chimneys instead of only one, the ventilation flow rate increased from 61 to 70.9%. The effect of the height of the chimney on the average of CO2 concentrations inside the hall was examined. The modeled height rates (1, 3, 5, and 7 m, respectively) were improved to 26%, 33.6%, and 48.7%, respectively.

scholarly journals An Investigation on Natural Window Ventilation: Improving Indoor Air Quality and Energy Efficiency in an Office Building

2021 ◽  
Author(s):  
Emine Şen ◽  
◽  
Touraj Ashrafian ◽  
Keyword(s):  
Energy Efficiency ◽  
Air Quality ◽  
Indoor Air Quality ◽  
Air Temperature ◽  
Indoor Air ◽  
Natural Ventilation ◽  
Indoor Air Pollution ◽  
Climatic Conditions ◽  
Office Building ◽  
Building Energy Efficiency

With the increment in time spent indoors, the contingence between building occupants and indoor air pollution has been lengthened. Accordingly, indoor air quality became a significant factor since the poor conditions can influence the occupants’ health and efficiency. Indoor air quality is mainly concerned with physical and thermophysical factors in conditioned environments and is related to occupants’ satisfaction levels on a variety of variables such as fresh air adequacy, air temperature, odor, humidity, and air velocity. This paper aims to investigate natural ventilation occupant-control methods to improve indoor air quality and increase building energy efficiency considering clean air intake levels and indoor air temperature levels. For this, variables related to climatic conditions, ventilation systems, and occupant’s control on window opening were investigated to provide healthy and liveable conditions. To comply with these goals, in an open-plan office building, the levels of indoor air quality were determined with the help of DesignBuilder simulation by comparing obtained values under different case modeling variations.

scholarly journals Indoor Air Quality: Assessment of Dangerous Substances in Incense Products

2021 ◽  
Vol 18 (15) ◽  
pp. 8086
Author(s):  
Gabriela Ventura Silva ◽  
Anabela O. Martins ◽  
Susana D. S. Martins
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Indoor Air Pollution ◽  
Gaseous Emissions ◽  
Limit Values ◽  
Cone Type ◽  
Guideline Values ◽  
Taking Action ◽  
At Home

Indoor air pollution has obtained more attention in a moment where “stay at home” is a maximum repeated for the entire world. It is urgent to know the sources of pollutants indoors, to improve the indoor air quality. This study presents some results obtained for twelve incense products, used indoors, at home, and in temples, but also in spa centers or yoga gymnasiums, where the respiratory intensity is high, and the consequences on health could be more severe. The focus of this study was the gaseous emissions of different types of incense, performing a VOC screening and identifying some specific VOCs different from the usual ones, which are known or suspected to cause severe chronic health effects: carcinogenic, mutagenic, and reprotoxic. Thirteen compounds were selected: benzene, toluene, styrene, naphthalene, furfural, furan, isoprene, 2-butenal, phenol, 2-furyl methyl ketone, formaldehyde, acetaldehyde, and acrolein. The study also indicated that incense cone type shows a higher probability of being more pollutant than incense stick type, as from the 12 products tested, four were cone type, and three of them were in the group of the four higher polluters. Benzene and formaldehyde presented worrying levels in the major part of the products, above guideline values established by the WHO. Unfortunately, there are no limit values established for indoor air for all the compounds studied, but this fact should not exempt us from taking action to alert the population to the potential dangers of using those products. From this study, acetaldehyde, acrolein, furfural, and furan emerge as compounds with levels to deserve attention.

scholarly journals Window operation behaviour and indoor air quality during lockdown: A monitoring-based simulation-assisted study in London

2021 ◽  
pp. 014362442110177
Author(s):  
Farhang Tahmasebi ◽  
Yan Wang ◽  
Elizabeth Cooper ◽  
Daniel Godoy Shimizu ◽  
Samuel Stamp ◽  
...  
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Energy Demand ◽  
Natural Ventilation ◽  
Probabilistic Models ◽  
Performance Model ◽  
Outdoor Environment ◽  
Ventilation Strategies ◽  
The Impact

The Covid-19 outbreak has resulted in new patterns of home occupancy, the implications of which for indoor air quality (IAQ) and energy use are not well-known. In this context, the present study investigates 8 flats in London to uncover if during a lockdown, (a) IAQ in the monitored flats deteriorated, (b) the patterns of window operation by occupants changed, and (c) more effective ventilation patterns could enhance IAQ without significant increases in heating energy demand. To this end, one-year’s worth of monitored data on indoor and outdoor environment along with occupant use of windows has been used to analyse the impact of lockdown on IAQ and infer probabilistic models of window operation behaviour. Moreover, using on-site CO2 data, monitored occupancy and operation of windows, the team has calibrated a thermal performance model of one of the flats to investigate the implications of alternative ventilation strategies. The results suggest that despite the extended occupancy during lockdown, occupants relied less on natural ventilation, which led to an increase of median CO2 concentration by up to 300 ppm. However, simple natural ventilation patterns or use of mechanical ventilation with heat recovery proves to be very effective to maintain acceptable IAQ. Practical application: This study provides evidence on the deterioration of indoor air quality resulting from homeworking during imposed lockdowns. It also tests and recommends specific ventilation strategies to maintain acceptable indoor air quality at home despite the extended occupancy hours.

scholarly journals Indoor Air Quality (IAQ): Accuracy of Natural Ventilation for Temperature, Air Flow Rate and Relative Humidity (RH) in School Building Classrooms

2018 ◽  
Vol 7 (3.9) ◽  
pp. 42
Author(s):  
Norsafiah Norazman ◽  
Adi Irfan Che Ani ◽  
Nor Haslina Ja’afar ◽  
Muhamad Azry Khoiry
Keyword(s):  
Air Quality ◽  
Relative Humidity ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Natural Ventilation ◽  
Air Flow ◽  
Weather Conditions ◽  
Potential Health ◽  
The Hours ◽  
Hot Weather

Indoor Air Quality (IAQ) is an essential matter in achieving students’ satisfaction for the learning process. Building’s orientation is a factor that may encourage sufficient natural ventilation for the classroom occupants. Inadequate ventilation is an issue for most existing classrooms. The purpose of this paper is to analyze the accuracy of natural ventilation in classrooms. Therefore, experimental on 20 classrooms has been conducted by using Multipurpose Meter at secondary school buildings in Malaysia. The findings indicated that the accuracy of natural ventilation testing was below the permissible limits throughout the hours monitored, thus this may cause potential health hazards to the students. Temperature and air flow rates were lower than 23 °C and 0.15 m/s respectively, it fulfilled the basic requirements as a standard learning environment. However, measurements taken showed the overall relative humidity (RH) in the classrooms can be categorized as acceptable with 40% to 70% range. On the basis of these findings, it is evident that naturally ventilated classrooms are important especially due to energy efficiency, whereas mechanical ventilation should only be installed as an alternative under extremely hot weather conditions.   

The Potential of Natural Ventilation in Single-Sided Ventilated Apartment to Improve Indoor Thermal Comfort and Air Quality

2011 ◽  
Author(s):  
M. F. Mohamed ◽  
M. Behnia ◽  
S. King ◽  
D. Prasad
Keyword(s):  
Air Quality ◽  
Thermal Comfort ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Natural Ventilation ◽  
Architectural Element ◽  
Flat Design ◽  
Effective Ventilation ◽  
Computational Fluid Dynamics Cfd ◽  
Ventilation Performance

Cross ventilation is a more effective ventilation strategy in comparison to single-sided ventilation. In the NSW Residential Flat Design Code1 (RFDC) the majority of apartments are required to adopt cross ventilation. However, in the case of studio and one-bedroom apartments, it is acknowledged that single-sided ventilation may prevail. Deep plan studio and one-bedroom apartments may achieve lower amenity of summer thermal comfort and indoor air quality where mechanical ventilation is not provided by air conditioning. Since compliance with the code may allow up to 40% of apartments in a development in Sydney to be single sided, it is important to understand the natural ventilation performance of such apartments. The objective of this paper is to investigate the natural ventilation potential in single-sided ventilated apartments to improve indoor air quality and thermal comfort. This investigation includes simulating various facade treatments involving multiple opening and balcony configurations. Balcony configurations are included in this study because, in Sydney, a balcony is a compulsory architectural element in any apartment building. The study uses computational fluid dynamics (CFD) software to simulate and predict the ventilation performance of each apartment configuration. This study suggests that properly configured balconies and openings can significantly improve indoor ventilation performance for enhanced indoor air quality and thermal comfort, by optimizing the available prevailing wind. However, it is important to note that inappropriately designed fac¸ade treatments also could diminish natural ventilation performance.

The effect of natural ventilation strategy on indoor air quality in schools

2017 ◽  
Vol 595 ◽  
pp. 894-902 ◽  
Author(s):  
Luca Stabile ◽  
Marco Dell'Isola ◽  
Aldo Russi ◽  
Angelamaria Massimo ◽  
Giorgio Buonanno
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Natural Ventilation ◽  
Ventilation Strategy

scholarly journals Remote Work and the Environment: Exploratory Analysis of Indoor Air Quality of Commercial Offices and the Home Office

2021 ◽  
Author(s):  
Kamrie Sarnosky ◽  
Mark Benden ◽  
Leslie Cizmas ◽  
Annette Regan ◽  
Garett Sansom
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Indoor Air Pollution ◽  
Home Office ◽  
Adverse Health Effects ◽  
Home Based ◽  
Increased Risk ◽  
Carbon Dioxide Co2 ◽  
Total Volatile Organic Compounds

Abstract Background: The COVID-19 pandemic has accelerated an already existing trend of individuals increasingly working remotely. With the growing popularity of remote working, specifically in a home office, there is a critical need to better understand and characterize the potential environmental differences between these two spaces. Indoor air pollution can have adverse health effects and impair cognitive functioning. Methods: This small pilot cohort study (N=22) recruited home and office workers to better understand the indoor air quality between these spaces. Air contaminants collected and assessed included PM10 and PM2.5, carbon dioxide (CO2), and total volatile organic compounds (TVOCs). Results: Findings showed a strong statistically significant increase in all measured variables within homes in comparison to traditional offices (p<0.001). For instance, The mean PM2.5 level in the traditional office space was 1.93 µg/m3 whereas it was more than twice this amount (5.97 µg/m3) in home offices.Conclusion: These results indicate that those who work from home are at increased risk due to longer exposures to higher levels of certain contaminants, the importance to better develop interventions to mitigate this reality is underscored by the fact that many workers will be moving to home-based offices in the coming years.

scholarly journals Association between Human Health and Indoor Air Pollution in Saudi Arabia: Indoor Environmental Quality Survey

2020 ◽  
pp. 57-66
Author(s):  
Mohd Saleem ◽  
Mohd Adnan Kausar ◽  
Fahmida Khatoon ◽  
Sadaf Anwar ◽  
Syed Monowar Alam Shahid ◽  
...  
Keyword(s):  
Air Pollution ◽  
Air Quality ◽  
Indoor Air Quality ◽  
Human Health ◽  
Indoor Air ◽  
Indoor Air Pollution ◽  
Negative Impact ◽  
Natural Light ◽  
Common Symptom ◽  
Indoor Environmental Quality

In many aspects of life quality, bio-contaminants and indoor air quality have had catastrophic consequences, including a negative impact on human health with an increased prevalence of allergic respiratory reactions, asthma, and infectious diseases. We aimed to evaluate the quality of indoor air environment and find out the association between human health and indoor air pollution and also to assess the physical health status of a group of Saudi and non-Saudi populations during this pandemic. Also, we aimed to assess the most common health condition or symptoms associated with ventilation. A questionnaire was distributed online to test indoor air quality, ventilation status, common signs and symptoms of any allergy or mental status and their relationship to certain variables. A total of 362 respondents were included. Before living in the current home, flu or Influenza and chapped lips were more prevalent than allergies and chapped lips signs while living in the current home. (12.2% , 10.8% vs. 18.5% , 13.55% before and after respectively) Multiple colds were the second most common symptom (10.2%). Hoarse voice and headaches were the least common symptoms experienced; each constituted 4.4%. During the COVID-19 Pandemic, most respondents wore a facemask, approximately 76.5%; and almost one-third of respondents had bright natural light inside the current home (43.1%). The presence of natural light within the current home was significantly associated with symptoms experienced during living in the current house (p<0.05). Natural sunlight exposure could decrease allergic symptoms and minor health problems associated with poor ventilation and air quality indoors. In current living homes, the majority of respondents never used air purifiers (72.9 percent). In order to get attention from people to enhance the quality and ventilation mechanism of indoor air, special care and awareness of the effects of the use of air purifiers on human health is needed.

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