scholarly journals Experimental investigation to verify if excessive plastic sheeting shielding produce micro clusters of SARS-CoV-2

2021 ◽  
Author(s):  
Yo Ishigaki ◽  
Yuto Kawauchi ◽  
Shinji Yokogawa ◽  
Akira Saito ◽  
Hiroko Kitamura ◽  
...  
Keyword(s):  
Experimental Investigation ◽  
Indoor Air ◽  
Fluid Simulation ◽  
Local Infection ◽  
Tracer Technique ◽  
Plastic Sheet ◽  
Office Space ◽  
Exhaled Air ◽  
Negative Effect ◽  
Air Ventilation

We experimentally investigated indoor air ventilation using the CO2 tracer technique to verify the infection cluster of SARS-CoV-2 that erupted at an office space. Multi-placed observations revealed extremely low air change rates (0.1/h) at the site. The local infection clusters were observed several meters away from a door that is the only ventilation in the office, which suggests a negative effect of plastic sheeting shielding. The thermo-fluid simulation showed that the plastic sheet blocked the airflow and trapped the exhaled air in each partition cell. As risk suppression methods, improving air ventilation by opening windows and using fans were verified, and significant improvements (10-28/h) were observed for each partition cells.

scholarly journals Air Ventilation Performance of School Classrooms with Respect to the Installation Positions of Return Duct

2021 ◽  
Vol 13 (11) ◽  
pp. 6188
Author(s):  
Sungwan Son ◽  
Choon-Man Jang
Keyword(s):  
Air Quality ◽  
Numerical Analysis ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Three Dimensional ◽  
Cross Infection ◽  
School Students ◽  
Height Range ◽  
Air Ventilation ◽  
Ventilation Performance

For students, who spend most of their time in school classrooms, it is important to maintain indoor air quality (IAQ) to ensure a comfortable and healthy life. Recently, the ventilation performance for indoor air quality in elementary schools has emerged as an important social issue due to the increase in the number of days of continuous high concentrations of particulate matter. Three-dimensional numerical analysis has been introduced to evaluate the indoor airflow according to the installation location of return diffusers. Considering the possibility of the cross-infection of infectious diseases between students due to the direction of airflow in the classroom, the airflow angles of the average respiratory height range of elementary school students, between 1.0 and 1.5 m, are analyzed. Throughout the numerical analysis inside the classroom, it is found that the floor return system reduces the indoor horizontal airflow that causes cross-infection among students by 20% compared to the upper return systems. Air ventilation performance is also analyzed in detail using the results of numerical simulation, including streamlines, temperature and the age of air.

scholarly journals Indoor Air Quality Real-Time Monitoring in Airport Terminal Areas: An Opportunity for Sustainable Management of Micro-Climatic Parameters

Sensors ◽  
2018 ◽  
Vol 18 (11) ◽  
pp. 3798 ◽  
Author(s):  
Sara Zanni ◽  
Francesco Lalli ◽  
Eleonora Foschi ◽  
Alessandra Bonoli ◽  
Luca Mantecchini
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Real Time ◽  
Indoor Air ◽  
Electronic Monitoring ◽  
Ventilation System ◽  
Real Time Monitoring ◽  
Airport Terminal ◽  
Air Ventilation ◽  
Gaseous Contaminants

Indoor air quality (IAQ) management in public spaces is assuming a remarkable importance. Busy environments, like airport terminals, are currently regarded as possible hotspots and IAQ is a crucial element for passengers and staff protection, as well as a key aspect of airport passenger experience. A one-month monitoring period has been performed on IAQ in the airport of Bologna (Italy), as prototypal example of large regional airport. Four strategic areas within the airport have been equipped with electronic monitoring platforms, including different contaminants and two microclimatic sensors. Data suggest that daily variation in IAQ parameters typically follow the activity pattern of the different environments under study (i.e., passengers’ flows) for gaseous contaminants, where particulate matter counts oscillate in a definite range, with a significant role played by ventilation system. Gaseous contaminants show a correlation between indoor and outdoor concentrations, mainly due to airside activities. Micro-climatic comfort parameters have been tested to match with standards for commercial environments. As results appears in line with typical households IAQ values, the current air ventilation system appears to be adequate. Nevertheless, an integrated air management system, based on real-time monitoring, would lead to optimization and improvement in environmental and economical sustainability.

scholarly journals Quality of life control by selected methods of air exchange in a typical apartment building

2021 ◽  
Author(s):  
Iveta Bullová ◽  
Peter Kapalo ◽  
Dušan Katunský
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Allergic Diseases ◽  
Well Being ◽  
Indoor Climate ◽  
Apartment Building ◽  
Change Rate ◽  
Air Change Rate ◽  
Negative Effect

Air change rate is an important parameter for quantification of ventilation heat losses and also affects the indoor climate of buildings. Indoor air quality is significantly associated with ventilation. If air change isn't sufficient, trapped allergens, pollutants and irritants can degrade the indoor air quality and affect the well-being of a building's occupants. Many studies on ventilation and health have concluded that lower air change rates can have a negative effect on people’s health and low ventilation may result in an increase in allergic diseases. Quantification of air change rate is complicated, since it is affected by a number of parameters, of which the one of the most variable is the air-wind flow. This study aims to determination and comparison of values of the air change rate in two methods - by quantifying of aerodynamic coefficient Cp = Cpe - Cpi – so called aerodynamic quantification of the building and the methodology based on experimental measurements of carbon dioxide in the selected reference room in apartment building.

Association of Indoor Air Pollution with Rhinitis Symptoms, Atopy and Nitric Oxide Levels in Exhaled Air

2010 ◽  
Vol 153 (4) ◽  
pp. 403-412 ◽  
Author(s):  
Lars-Georg Hersoug ◽  
Lise Lotte N. Husemoen ◽  
Simon Francis Thomsen ◽  
Torben Sigsgaard ◽  
Betina H. Thuesen ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Air Pollution ◽  
Indoor Air ◽  
Indoor Air Pollution ◽  
Exhaled Air

scholarly journals The Fabrication of Geopolymer Foam Composites Incorporating Coke Dust Waste

Processes ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 1052
Author(s):  
Buczkowska Katarzyna ◽  
Chi Hiep Le ◽  
Petr Louda ◽  
Szczypiński Michał ◽  
Totka Bakalova ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Experimental Investigation ◽  
Residual Strength ◽  
Elevated Temperatures ◽  
Composite Foam ◽  
Coke Dust ◽  
Composite Foams ◽  
Negative Effect ◽  
Geopolymer Binder

This paper reports the results of an experimental investigation on the mechanical properties of geopolymer foams incorporating filler from the coke dust waste (CDW). In this work, CDW was used to replace a part of geopolymer paste at 5%, 10%, 20%, and 30% by geopolymer binder mass. The physico-mechanical properties and thermal resistance against high temperatures of CDW/geopolymer foams are presented. The primary results obtained show that the use of CDW in the production of geopolymer foam composites made it possible for them to achieve relatively good mechanical properties. However, the incorporation of the CDW into the geopolymer had a slightly negative effect on thermal conductivity, but significantly improved the mechanical strength of the final product. Moreover, this waste also helped the composite foam to achieve a structure with more uniform open pores distribution, compared to the pure foam. After exposure to elevated temperatures, the residual strength of the composite foams maintained well compared to the pure foams.

scholarly journals Overview of HOMEChem: House Observations of Microbial and Environmental Chemistry

2019 ◽  
Vol 21 (8) ◽  
pp. 1280-1300 ◽  
Author(s):  
D. K. Farmer ◽  
M. E. Vance ◽  
J. P. D. Abbatt ◽  
A. Abeleira ◽  
M. R. Alves ◽  
...  
Keyword(s):  
Experimental Investigation ◽  
Indoor Air ◽  
Large Scale ◽  
Environmental Chemistry

The House Observations of Microbial and Environmental Chemistry (HOMEChem) study was a large-scale collaborative experimental investigation probing indoor air composition and chemistry.

Monitoring of Selected Indoor Air Quality Parameters and Cooling Energy Usage in Hotel Restaurant Malaysia

2014 ◽  
Vol 564 ◽  
pp. 250-255
Author(s):  
M.M. Syafiq Syazwan ◽  
Mohammad Zainal M. Yusof ◽  
C.K. Chang ◽  
M.D. Amir Abdullah
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Quality Parameters ◽  
Internal Source ◽  
Energy Usage ◽  
Code Of Practice ◽  
Loads Analysis ◽  
Air Ventilation ◽  
Psychrometric Chart

Sensible (temperature) and latent (moisture) loads are the common load an air-conditioning (AC) system need to handle. Both loads are generated from conditioned space, internal source and outdoor air ventilation. This study is to monitor the indoor air quality IAQ in hotel restaurant and the results are compared with Malaysian standard MS1525 and Industry Code of Practice (COP) on IAQ 2010, Department of Safety and Health (DOSH) Malaysia. The AC system performance was also monitored to identify the actual cooling energy usage base on standard operations. Psychrometric chart was used to analyse the actual cooling energy required and identified the latent and sensible loads significantly. The result of the study shows the mean air temperature, relative humidity (RH), carbon dioxide (CO) and carbon monoxide (CO2) levels were within range as stipulated by standard and code of practice. Heat loads analysis on a psychrometric chart showed the total cooling energy as 296.2 kW; of which 196.3 kW was contributed to primary air unit (PAU) and 99.9 kW to air handling unit (AHU) respectively. The primary contribution for sensible and latent loads and recommendation of potential energy saving also been discussed to meet energy efficient in AC system while maintaining good indoor air quality in the restaurant.

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