The effect of increasing indoor ventilation on artificially generated aerosol particle counts

The COVID-19 global pandemic has caused millions of infections and deaths despite mitigation efforts that involve physical distancing, mask-wearing, avoiding indoor gatherings and increasing indoor ventilation. The purpose of this study was to compare ways to improve indoor ventilation and assess its effect on artificially generated aerosol counts. It was hypothesized that inbuilt kitchen vents would be more effective in reducing indoor aerosol counts than opening windows alone. A fixed amount of saline aerosol was dispersed in the experimental area using a nebulizer under constant temperature and a narrow range of humidity. A laser air quality monitor was used to record small particle counts every 30 minutes from baseline to 120 minutes for four different experimental groups for each combination of kitchen vents and windows. The results of the study demonstrate that aerosol counts were lowest with the kitchen exhaust vents on. This study suggests that liberal use of home exhaust systems like the kitchen vents could achieve significantly more air exchange than open windows alone and may present an effective solution to improving indoor ventilation, especially during the colder months when people tend to congregate indoors in closed spaces. There were no safety concerns involved when conducting this experiment.

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Impact on Air Quality of the COVID-19 Lockdown in the Urban Area of Palermo (Italy)

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17207375 ◽

2020 ◽

Vol 17 (20) ◽

pp. 7375 ◽

Cited By ~ 2

Author(s):

Marcello Vultaggio ◽

Daniela Varrica ◽

Maria Grazia Alaimo

Keyword(s):

Air Pollution ◽

Air Quality ◽

Urban Area ◽

Human Mobility ◽

Infected People ◽

National Crisis ◽

Global Pandemic ◽

Pm 10 ◽

The Impact

At the end of 2019, the first cases of coronavirus disease (COVID-19) were reported in Wuhan, China. Thereafter, the number of infected people increased rapidly, and the outbreak turned into a national crisis, with infected individuals all over the country. The COVID-19 global pandemic produced extreme changes in human behavior that affected air quality. Human mobility and production activities decreased significantly, and many regions recorded significant reductions in air pollution. The goal of our investigation was to evaluate the impact of the COVID-19 lockdown on the concentrations of the main air pollutants in the urban area of Palermo (Italy). In this study, the trends in the average concentrations of CO, NO2, O3, and PM10 in the air from 1 January 2020 to 31 July 2020 were compared with the corresponding average values detected at the same monitoring stations in Palermo during the previous five years (2015–2019). During the lockdown period (10 March–30 April), we observed a decrease in the concentrations of CO, NO2, and particulate matter (PM)10, calculated to be about 51%, 50%, and 45%, respectively. This confirms that air pollution in an urban area is predominantly linked to vehicular traffic.

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Aerosol particle and trace gas emissions from earthworks, road construction, and asphalt paving in Germany: Emission factors and influence on local air quality

Atmospheric Environment ◽

10.1016/j.atmosenv.2015.10.036 ◽

2015 ◽

Vol 122 ◽

pp. 662-671 ◽

Cited By ~ 14

Author(s):

Peter Faber ◽

Frank Drewnick ◽

Stephan Borrmann

Keyword(s):

Air Quality ◽

Aerosol Particle ◽

Road Construction ◽

Emission Factors ◽

Trace Gas ◽

Gas Emissions ◽

Trace Gas Emissions ◽

Asphalt Paving

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High resolution modelling of aerosol dispersion regimes during the CAPITOUL field experiment: from regional to local scale interactions

Atmospheric Chemistry and Physics ◽

10.5194/acp-11-7547-2011 ◽

2011 ◽

Vol 11 (15) ◽

pp. 7547-7560 ◽

Cited By ~ 4

Author(s):

B. Aouizerats ◽

P. Tulet ◽

G. Pigeon ◽

V. Masson ◽

L. Gomes

Keyword(s):

Air Quality ◽

High Resolution ◽

Field Experiment ◽

Aerosol Particle ◽

Pollutant Dispersion ◽

Local Scale ◽

Plume Dispersion ◽

Urban Dynamics ◽

The Impact ◽

Resolution Simulation

Abstract. High resolution simulation of complex aerosol particle evolution and gaseous chemistry over an atmospheric urban area is of great interest for understanding air quality and processes. In this context, the CAPITOUL (Canopy and Aerosol Particle Interactions in the Toulouse Urban Layer) field experiment aims at a better understanding of the interactions between the urban dynamics and the aerosol plumes. During a two-day Intensive Observational Period, a numerical model experiment was set up to reproduce the spatial distribution of specific particle pollutants, from the regional scales and the interactions between different cities, to the local scales with specific turbulent structures. Observations show that local dynamics depends on the day-regime, and may lead to different mesoscale dynamical structures. This study focuses on reproducing these fine scale dynamical structures, and investigate the impact on the aerosol plume dispersion. The 500-m resolution simulation manages to reproduce convective rolls at local scale, which concentrate most of the aerosol particles and can locally affect the pollutant dispersion and air quality.

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Indoor aerosol particle deposition and distribution: Numerical analysis for a one-zone ventilation system

Building Services Engineering Research and Technology ◽

10.1177/014362449501600304 ◽

1995 ◽

Vol 16 (3) ◽

pp. 141-147 ◽

Cited By ~ 10

Author(s):

W. Lu ◽

A.T. Howarth

Keyword(s):

Numerical Analysis ◽

Aerosol Particle ◽

Particle Deposition ◽

Ventilation System ◽

Indoor Aerosol

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Comparison of indoor aerosol particle concentration and deposition in different ventilated rooms by numerical method

Building and Environment ◽

10.1016/j.buildenv.2003.08.002 ◽

2004 ◽

Vol 39 (1) ◽

pp. 1-8 ◽

Cited By ~ 209

Author(s):

Bin Zhao ◽

Ying Zhang ◽

Xianting Li ◽

Xudong Yang ◽

Dongtao Huang

Keyword(s):

Numerical Method ◽

Aerosol Particle ◽

Particle Concentration ◽

Indoor Aerosol

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Machine Learning on the COVID-19 Pandemic, Human Mobility, and Air Quality: A Review

10.20944/preprints202103.0396.v1 ◽

2021 ◽

Author(s):

Md Mokhlesur Rahman ◽

Kamal Chandra Paul ◽

Md. Amjad Hossain ◽

G. G. Md. Nawaz Ali ◽

Md. Shahinoor Rahman ◽

...

Keyword(s):

Machine Learning ◽

Air Quality ◽

Urban Form ◽

Human Mobility ◽

Virus Transmission ◽

Past Research ◽

Policy Implications ◽

Viral Spread ◽

Global Pandemic ◽

Review Study

The ongoing COVID-19 global pandemic is affecting every facet of human lives (e.g., public health, education, economy, transportation, and the environment). This novel pandemic and citywide implemented lockdown measures are affecting virus transmission, people’s travel patterns, and air quality. Many studies have been conducted to predict the COVID-19 diffusion, assess the impacts of the pandemic on human mobility and air quality, and assess the impacts of lockdown measures on viral spread with a range of Machine Learning (ML) techniques. This review study aims to analyze results from past research to understand the interactions among the COVID-19 pandemic, lockdown measures, human mobility, and air quality. The critical review of prior studies indicates that urban form, people's socioeconomic and physical conditions, social cohesion, and social distancing measures significantly affect human mobility and COVID-19 transmission. During the COVID-19 pandemic, many people are inclined to use private transportation for necessary travel purposes to mitigate coronavirus-related health problems. This review study also noticed that COVID-19 related lockdown measures significantly improve air quality by reducing the concentration of air pollutants, which in turn improves the COVID-19 situation by reducing respiratory-related sickness and deaths of the people. It is argued that ML is a powerful, effective, and robust analytic paradigm to handle complex and wicked problems such as a global pandemic. This study also discusses policy implications, which will be helpful for policymakers to take prompt actions to moderate the severity of the pandemic and improve urban environments by adopting data-driven analytic methods.

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Temperature-induced microbubbles within natural marine samples may inflate small-particle counts in a Coulter Counter

Marine Ecology Progress Series ◽

10.3354/meps09513 ◽

2012 ◽

Vol 450 ◽

pp. 275-280

Author(s):

EJ Rice ◽

C Panzeca ◽

GM Stewart

Keyword(s):

Small Particle ◽

Coulter Counter ◽

Marine Samples ◽

Particle Counts

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In-depth characterization of submicron particulate matter inter-annual variations at a street canyon site in northern Europe

Atmospheric Chemistry and Physics ◽

10.5194/acp-21-6297-2021 ◽

2021 ◽

Vol 21 (8) ◽

pp. 6297-6314

Author(s):

Luis M. F. Barreira ◽

Aku Helin ◽

Minna Aurela ◽

Kimmo Teinilä ◽

Milla Friman ◽

...

Keyword(s):

Particulate Matter ◽

Air Quality ◽

Aerosol Particle ◽

Street Canyon ◽

Particle Number ◽

Large Fraction ◽

Northern Europe ◽

Time Resolved ◽

Inorganic Species ◽

Pollution Episodes

Abstract. Atmospheric aerosols play an important role in air pollution. Aerosol particle chemical composition is highly variable depending on the season, hour of the day, day of the week, meteorology, and location of the measurement site. Long measurement periods and highly time-resolved data are required in order to achieve a statistically relevant amount of data for assessing those variations and evaluating pollution episodes. In this study, we present continuous atmospheric PM1 (particulate matter < 1 µm) concentration and composition measurements at an urban street canyon site located in Helsinki, Finland. The study was performed for 4.5 years (2015–2019) and involved highly time-resolved measurements by taking advantage of a suite of online state-of-the-art instruments such as an aerosol chemical speciation monitor (ACSM), a multi-angle absorption photometer (MAAP), a differential mobility particle sizer (DMPS), and an Aethalometer (AE). PM1 consisted mostly of organics, with mean mass concentrations of 2.89 µg m−3 (53 % of PM1) followed by inorganic species (1.56 µg m−3, 29 %) and equivalent black carbon (eBC, 0.97 µg m−3, 18 %). A trend analysis revealed a decrease in BC from fossil fuel (BCFF), organics, and nitrate over the studied years. Clear seasonal and/or diurnal variations were found for the measured atmospheric PM1 constituents. Particle number and mass size distributions over different seasons revealed the possible influence of secondary organic aerosols (SOAs) during summer and the dominance of ultrafine traffic aerosols during winter. The seasonality of measured constituents also impacted the particle's coating and absorptive properties. The investigation of pollution episodes observed at the site showed that a large fraction of aerosol particle mass was comprised of inorganic species during long-range transport, while during local episodes eBC and organics prevailed together with elevated particle number concentration. Overall, the results increased knowledge of the variability of PM1 concentration and composition in a Nordic traffic site and its implications on urban air quality. Considering the effects of PM mitigation policies in northern Europe in the last decades, the results obtained in this study may be considered illustrative of probable future air quality challenges in countries currently adopting similar environmental regulations.

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