Aerial Transmission of the SARS-CoV-2 Virus through Environmental E-Cigarette Aerosols: Implications for Public Policies

We discuss the implications of possible contagion of COVID-19 through e-cigarette aerosol (ECA) for prevention and mitigation strategies during the current pandemic. This is a relevant issue when millions of vapers (and smokers) must remain under indoor confinement and/or share public outdoor spaces with non-users. The fact that the respiratory flow associated with vaping is visible (as opposed to other respiratory activities) clearly delineates a safety distance of 1–2 m along the exhaled jet to prevent direct exposure. Vaping is a relatively infrequent and intermittent respiratory activity for which we infer a mean emission rate of 79.82 droplets per puff (6–200, standard deviation 74.66) comparable to mouth breathing, it adds into shared indoor spaces (home and restaurant scenarios) a 1% extra risk of indirect COVID-19 contagion with respect to a “control case” of existing unavoidable risk from continuous breathing. As a comparative reference, this added relative risk increases to 44–176% for speaking 6–24 min per hour and 260% for coughing every 2 min. Mechanical ventilation decreases absolute emission levels but keeps the same relative risks. As long as direct exposure to the visible exhaled jet is avoided, wearing of face masks effectively protects bystanders and keeps risk estimates very low. As a consequence, protection from possible COVID-19 contagion through vaping emissions does not require extra interventions besides the standard recommendations to the general population: keeping a social separation distance of 2 m and wearing of face masks.

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Reduction of exposure to simulated respiratory aerosols using ventilation, physical distancing, and universal masking

10.1101/2021.09.16.21263702 ◽

2021 ◽

Author(s):

Jayme P. Coyle ◽

Raymond C Derk ◽

William G Lindsley ◽

Theresa Boots ◽

Francoise M. Blachere ◽

...

Keyword(s):

Indoor Environment ◽

Respiratory Activity ◽

Aerosol Particles ◽

Inhalation Exposure ◽

Mitigation Strategies ◽

Engineering Controls ◽

Particle Exposure ◽

Adequate Ventilation ◽

Respiratory Droplets ◽

Indoor Spaces

To limit community spread of SARS-CoV-2, CDC recommends universal masking indoors, maintaining 1.8 m of physical distancing, adequate ventilation, and avoiding crowded indoor spaces. Several studies have examined the independent influence of each control strategy in mitigating transmission in isolation, yet controls are often implemented concomitantly within an indoor environment. To address the influence of physical distancing, universal masking, and ventilation on very fine respiratory droplets and aerosol particle exposure, a simulator that coughed and exhaled aerosols (the source) and a second breathing simulator (the recipient) were placed in an exposure chamber. When controlling for the other two mitigation strategies, universal masking with 3-ply cotton masks reduced exposure to 0.3-3 μm coughed and exhaled aerosol particles by > 77% compared to unmasked tests, whereas physical distancing (0.9 or 1.8 m) significantly changed exposure to cough but not exhaled aerosols. The effectiveness of ventilation depended upon the respiratory activity, i.e., coughing or breathing, as well as the duration of exposure time. Our results demonstrate that a combination of administrative and engineering controls can reduce personal inhalation exposure to potentially infectious very fine respiratory droplets and aerosol particles within an indoor environment.

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Effects of Building Microclimate on the Thermal Environment of Traditional Japanese Houses during Hot-Humid Summer

Buildings ◽

10.3390/buildings9010022 ◽

2019 ◽

Vol 9 (1) ◽

pp. 22 ◽

Cited By ~ 1

Author(s):

Ayaz Hosham ◽

Tetsu Kubota

Keyword(s):

Surface Temperature ◽

Thermal Environment ◽

Cooling Effect ◽

Shading Effect ◽

Indoor Thermal Environment ◽

Air Temperatures ◽

Outdoor Spaces ◽

Open Plan ◽

Indoor Spaces

The purpose of this study was to investigate the effects of building microclimate on the indoor thermal environment of traditional Japanese houses, focusing especially on the shading effect of trees as well as the cooling effect of spraying water. Basically, the indoor thermal environment was found to follow the outdoor conditions due to the open-plan and lightweight wooden structure. Nevertheless, air temperatures of the living rooms in the two case study houses were lower than the corresponding outdoors by approximately 0.5 °C and 2 °C, respectively. It was found that the semi-outdoor spaces acted as thermal buffers for promoting cross-ventilation as well as pre-cooling to provide “warm but breezy” conditions to the surrounding indoor spaces. The results showed that the surface temperature of semi-outdoor spaces can be reduced by shading and water spraying, among which shading has prolonged effects and water spraying can reduce the surface temperature during peak hours and the following night.

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Coronavirus Disease 2019 (COVID-19) Seropositivity and Asymptomatic Rates in Healthcare Workers Are Associated with Job Function and Masking

Clinical Infectious Diseases ◽

10.1093/cid/ciaa1684 ◽

2020 ◽

Cited By ~ 1

Author(s):

Matthew D Sims ◽

Gabriel N Maine ◽

Karen Lins Childers ◽

Robert H Podolsky ◽

Daniel R Voss ◽

...

Keyword(s):

Healthcare Workers ◽

Mitigation Strategies ◽

High Rate ◽

Blood Collection ◽

Nursing Support ◽

Direct Exposure ◽

Positive Individual ◽

Asymptomatic Individuals ◽

Major Donors ◽

Frontline Healthcare Workers

Abstract Background Although the risk of exposure to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is higher for frontline healthcare workers, not all personnel have similar risks. Determining infection rate is difficult due to the limits on testing and the high rate of asymptomatic individuals. Detection of antibodies against SARS-CoV-2 may be useful for determining prior exposure to the virus and assessing mitigation strategies, such as isolation, masks, and other protective equipment. Methods An online assessment that included demographic, clinical, and exposure information and a blood sample was collected from 20 614 participants out of ~43 000 total employees at Beaumont Health, which includes 8 hospitals distributed across the Detroit metropolitan area in southeast Michigan. The presence of anti-SARS-CoV-2 IgG was determined using the EUROIMMUN assay. Results A total of 1818 (8.8%) participants were seropositive between April 13 and May 28, 2020. Among the seropositive individuals, 44% reported that they were asymptomatic during the month prior to blood collection. Healthcare roles such as phlebotomy, respiratory therapy, and nursing/nursing support exhibited significantly higher seropositivity. Among participants reporting direct exposure to a Coronavirus Disease 2019 (COVID-19) positive individual, those wearing an N95/PAPR mask had a significantly lower seropositivity rate (10.2%) compared to surgical/other masks (13.1%) or no mask (17.5%). Conclusions Direct contact with COVID-19 patients increased the likelihood of seropositivity among employees but study participants who wore a mask during COVID-19 exposures were less likely to be seropositive. Additionally, a large proportion of seropositive employees self-reported as asymptomatic. (Funded by Beaumont Health and by major donors through the Beaumont Health Foundation) ClinicalTrials.gov number NCT04349202

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Treatment with Dry Hydrogen Peroxide Accelerates the Decay of Severe Acute Syndrome Coronavirus-2 on Non-porous Hard Surfaces

10.21203/rs.3.rs-448407/v1 ◽

2021 ◽

Author(s):

Yan-Jang S. Huang ◽

Ashley N. Bilyeu ◽

Wei-Wen Hsu ◽

Susan M. Hettenbach ◽

Joshua L. Willix ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Infectious Virus ◽

Mitigation Strategies ◽

Control Group ◽

Ambient Atmosphere ◽

Surface Areas ◽

Glass Slides ◽

Pathogen Reduction ◽

Indoor Spaces ◽

Hydrogen Peroxide Vapor

Abstract Background. Disinfection of contaminated or potentially contaminated surfaces has become an integral part of the mitigation strategies for controlling coronavirus disease 2019. Whilst a broad range of disinfectants are effective in inactivating severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), application of disinfectants has a low throughput in areas that receive treatments. Disinfection of large surface areas often involves the use of reactive microbiocidal materials, including ultraviolet germicidal irradiation, chlorine dioxide, and hydrogen peroxide vapor. Albeit these methods are highly effective in inactivating SARS-CoV-2, the deployment of these approaches creates unacceptable health hazards and precludes the treatment of occupied indoor spaces using existing disinfection technologies. Deployment of dry hydrogen peroxide (DHP) is an emerging pathogen reduction technology, which produces hydrogen peroxide in the ambient atmosphere at 5 and 25 parts per billion using a commercially available catalytic unit. The low concentration of hydrogen peroxide released using DHP technology has been found to be tolerated by humans in indoor spaces and is effective in inactivating bacterial pathogens responsible for nosocomial infections. In this study, the feasibility of using DHP in inactivating SARS-CoV-2 on contaminated surfaces in large indoor spaces was evaluated. Methods. Glass slides were inoculated with SARS-CoV-2 and treated with DHP for up to 24 hours. Residual infectious virus samples were eluted and titrated in African green monkey VeroE6 cells. Results. In comparison with the observed relatively high stability of SARS-CoV-2 on contaminated glass slides in the control group, residual infectious titers of glass slides inoculated with SARS-CoV-2 were significantly reduced after receiving 120 minutes of DHP treatment. Conclusions. The accelerated decay of SARS-CoV-2 on contaminated glass slides suggests that treatment with DHP can be an effective surface disinfection method for occupied indoor spaces.

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Analytic modeling and risk assessment of aerial transmission of SARS-CoV-2 virus through vaping expirations in shared micro-environments

10.21203/rs.3.rs-340115/v1 ◽

2021 ◽

Author(s):

Roberto Sussman ◽

Eliana Golberstein ◽

Riccardo Polosa

Keyword(s):

Mechanical Ventilation ◽

Risk Model ◽

Case Scenario ◽

Direct Exposure ◽

Containment Measures ◽

Nicotine Consumption ◽

Contagion Risk ◽

Droplet Nuclei ◽

Respiratory Droplets ◽

Indoor Spaces

Abstract Background. E-cigarettes are an important harm reduction tool that provides smokers an alternative for nicotine consumption that is much safer than smoking. It is important to asses its safety under preventive and containment measures undertaken during the COVID-19 pandemic. Methods. We develop a theoretical risk model to assess the contagion risk by aerial transmission of the SARS-CoV-2 virus carried by e–cigarette aerosol (ECA) in shared indoor spaces, a home and restaurant scenarios, with natural and mechanical ventilation, with and without face masks. We also provide the theoretical elements to explain the visibility of exhaled ECA, which has important safety implications. Results. In a home or restaurant scenarios bystanders exposed to ECA expirations by an infectious vaper (and not wearing face masks) face a 1% increase of risk of contagion with respect to a “control case” scenario defined by exclusively rest breathing without vaping. This relative added risk becomes 5 - 17% for high intensity vaping, 44 - 176% and over 260% for speaking for various periods or coughing (all without vaping). Mechanical ventilation significantly decrease infective emissions but keep the same proportionality in risk percentages. Face masks of common usage effectively protect wearers from respiratory droplets and droplet nuclei possibly emitted by mask-less vapers as long as they avoid direct exposure to the visible exhaled vaping jet. Conclusions. Vaping emissions in shared indoor spaces involve only a minuscule added risk of COVID-19 contagion with respect to the already existing (unavoidable) risk from continuous breathing, significantly less than speaking or coughing. Protection of bystanders from this contagion does not require extra preventive measures besides those already recommended (1.5 meters separation and wearing face masks).

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A Relative Study of Contemporary Residential Landscape Architecture: From the Local to the Global Aspect

Journal of Art Architecture and Built Environment ◽

10.32350/jaabe.42.05 ◽

2021 ◽

Vol 4 (2) ◽

Author(s):

Shifa Rasul Khawaja ◽

Saad Mujahid ◽

Ayesha Mehmood Malik ◽

Memoona Rashid

Keyword(s):

City Planning ◽

Open Spaces ◽

Layout Planning ◽

Residential Landscape ◽

Outdoor Spaces ◽

Global Aspect ◽

Planning Strategies ◽

Main Component ◽

Residential Quarters ◽

Indoor Spaces

The location of residential quarters has a deep connection with the pattern of everyday life. It is not always significant for social activities; however, it is the main component in city planning. Along with the improvement of the society and economy, the landscape of residences is likewise changing. This paper aims to discuss the planning strategies of residential landscape from a socio-technical perceptive. A diverse approach was implemented for collecting data due to the uncertain situation around the world because of COVID19 including personal archival data, LDA authority, building regulations, research articles and interviews. The variables adapted for the current research are: drift from outdoor spaces to indoor spaces, orientation of design and spatial layout and practices diffusion. The study suggests that the dynamics of space and practices can normalize the unsustainable arrangements rooted in social organizations. The increased consumption of electrical appliances and specification of spaces has changed the culture into an unsuitable indoor layout planning and has neglected the use of outdoor areas in contemporary societies. This study can help to bring the implementation of house planning into a broader perspective globally as there is a comparison drawn between the local and international landscaped signing by a renowned landscape architect "Geoffrey Bawa". Keywords: architecture, contemporary and landscape, open spaces, orientation, residential planning

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Metagenomic Insights Into the Microbial Communities of Inert and Oligotrophic Outdoor Pier Surfaces of a Coastal City

10.21203/rs.3.rs-526930/v1 ◽

2021 ◽

Author(s):

Xinzhao Tong ◽

Marcus H. Y. Leung ◽

Zhiyong Shen ◽

Justin Y. Y. Lee ◽

Christopher E. Mason ◽

...

Keyword(s):

Microbial Communities ◽

Bacterial Species ◽

Gene Clusters ◽

Taxonomic Composition ◽

Metagenomic Sequencing ◽

Biosynthetic Gene Clusters ◽

Metabolic Functions ◽

Outdoor Spaces ◽

Genomic Characterization ◽

Indoor Spaces

Abstract Background: Studies of the microbiomes on surfaces in built environment have largely focused on indoor spaces, while outdoor spaces have received far less attention. Piers are engineered infrastructures commonly found in coastal areas, and due to their unique locations at the interface between terrestrial and aquatic ecosystems, pier surfaces are likely to harbor interesting microbiology. In this study, the microbiomes on the metal and concrete surfaces at nine piers located along the coastline of Hong Kong were investigated by metagenomic sequencing. The roles played by different factors in shaping the taxonomic composition and functional traits of the pier surface microbiomes were determined. Metagenome-assembled genomes were reconstructed and their putative biosynthetic gene clusters were characterized in detail.Results: Surface material was found to be the strongest factor in structuring the taxonomic and functional compositions of the pier surface microbiomes. Corrosion-related bacteria were significantly enriched on metal surfaces, consistent with the pitting corrosion observed. The differential enrichment of taxa mediating biodegradation suggests differences between the metal and concrete surfaces in terms of specific xenobiotics being potentially degraded. Genome-centric analysis detected the presence of many novel species, with the majority of them belonging to the phylum Proteobacteria. Genomic characterization showed that the potential metabolic functions and secondary biosynthetic capacity were largely governed by taxonomy, rather than surface attributes and geography. Conclusions: Pier surfaces are a rich reservoir of abundant novel bacterial species. Members of the surface microbial communities use different mechanisms to counter the stresses under oligotrophic conditions. A better understanding of the outdoor surface microbiomes located in different environments should enhance the ability to maintain outdoor surfaces of infrastructures.

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MAKNA AMBATIK – PALMERAH

Jurnal Sains, Teknologi, Urban, Perancangan, Arsitektur (Stupa) ◽

10.24912/stupa.v2i1.6845 ◽

2020 ◽

Vol 2 (1) ◽

pp. 901

Author(s):

Indra Lesmana ◽

Petrus Rudi Kasimun

Keyword(s):

Open Space ◽

Public Spaces ◽

Open Spaces ◽

Outdoor Spaces ◽

Recreation Areas ◽

Public Areas ◽

Local Residents ◽

Ray Oldenburg ◽

The City ◽

Indoor Spaces

The existence of an open space, is truly important to nowadays urban society. Because basically, community of a city has been bounded to open spaces around that city. The need of a thirdplace in a city, now, is way more than just a regular, it became a lifestyle. This thirdplace phenomena give impacts to the usage of outdoor spaces in the city which used to be indoor spaces, now became outdoor ones (public areas). What used to be a mall and a café that are favorites, now turning into outdoor spaces such as parks, streets (pedestrians), public spaces for children, recreation areas, and so on. Jakarta, especially in Palmerah, open spaces are very rarely found. In the other side, Palmerah used to be known for its batik, but now it’s already all gone. Batik as the main program that supports this thirdplace is expected to be able to accommodate the work or activities of local residents. Hold on to Ray Oldenburg’s theory about the third place criteria, batik in this design is intended as a medium for local residents to meet, greet, and interact. With this, batik media is able to accommodate the need of a thirdplace itself. However still, open spaces in this design has the largest percentage as public spaces for local residents to do some activities and interactions. Batik phases are realized in creating existing spaces; starting from seeing, then feeling, and finally doing. Batik produced by locals can be resold and later become their income. Plots of spaces, materials, wall tears, and batik carvings are also highlighted in this building to create characteristic of this Ambatik building. With Ambatik, all ages, all genders, all types of ethnicity, culture, and race, can be united without any difference.AbstrakKeberadaan ruang luar sangatlah penting bagi masyarakat kota saat ini. Pada dasarnya, masyarakat memiliki keterikatan pada ruang-ruang terbuka kota. Sekarang, Kebutuhan tempat ketiga di dalam suatu kota sudah lebih dari sekedar kebutuhan biasa, tetapi sudah menjadi gaya hidup. Fenomena tempat ketiga berdampak pada penggunaan ruang luar yang pada awalnya dari penggunaan ruang dalam, mulai beralih ke ruang luar (ruang publik). Yang semula mall dan kafe menjadi ruang favorit, sekarang beralih ke ruang luar publik seperti taman, jalan (pedestrian), RPTRA, tempat rekreasi dan sebagainya. Di Jakarta, tepatnya di Palmerah, ruang-ruang terbuka bagi warga sekitar sangatlah jarang ditemui. Di satu sisi, Palmerah yang dalam sejarah dikenal oleh batiknya, sekarang sudah menghilang. Ambatik hadir untuk menunjang tempat ketiga di kawasan Palmerah, yang diharapkan mampu mewadahi kegiatan ataupun aktivitas dari warga sekitar, sekaligus menghidupkan kembali identitas batik di Palmerah. Dengan teori Ray Oldenburg mengenai kriteria sebuah tempat ketiga, batik dalam rancangan ini dimaksudkan sebagai media bagi warga sekitar untuk bertemu, bersapa dan berinteraksi. Ruang-ruang terbuka dalam rancangan ini juga berguna sebagai ruang publik bagi warga sekitar untuk beraktivitas, berinteraksi untuk melakukan kegiatan seni dan budaya. Fase-fase batik juga diwujudkan dalam menciptakan ruang-ruang yang ada, mulai dari melihat, kemudian merasakan, dan melakukan. Dengan hadirnya Ambatik, diharap mampu meningkatkan relasi antar warga, pemahaman baru tentang batik, dan kesadaran akan tradisi.

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Associations of Acute Exposure to Airborne Pollutants with COVID-19 Infection: Evidence from China

10.21203/rs.3.rs-273170/v1 ◽

2021 ◽

Author(s):

Bingqing Lu ◽

Na Wu ◽

Jiakui Jiang ◽

Xiang Li

Keyword(s):

Relative Humidity ◽

Environmental Factors ◽

Generalized Additive Model ◽

Additive Model ◽

Mitigation Strategies ◽

Atmospheric Pollutants ◽

Acute Exposure ◽

Airborne Pollutants ◽

Relative Risks ◽

Pollutant Concentrations

Abstract The outbreak of COVID-19, caused by SARS-CoV-2 has spread across many countries globally. Greatly limited study concerned the effect of airborne pollutants on COVID-19 infection, while exposure to airborne pollutants may harm human health. This paper aimed to examine the associations of acute exposure to ambient atmospheric pollutants to daily newly COVID-19 confirmed cases in 41 Chinese cities. Using a generalized additive model with Poisson distribution controlling for temperature and relative humidity, we evaluated the association between pollutant concentrations and daily COVID-19 confirmation at single-city level and multi-city level. We observed a 10 μg/m3 rise in levels of PM2.5 (lag 0−14), O3 (lag 0−1), SO2 (lag 0) and NO2 (lag 0−14) were positively associated with relative risks of 1.050 (95% CI: 1.028, 1.073), 1.011 (1.007, 1.015), 1.052 (1.022, 1.083) and 1.094 (1.028, 1.164) of daily newly confirmed cases, respectively. Further adjustment for other pollutants did not change the associations materially (excepting in the model for SO2). Our results indicated that COVID-19 incidence may be susceptible to airborne pollutants such as PM2.5, O3, SO2 and NO2, and mitigation strategies of environmental factors are required to prevent spreading.

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Spatial data managements in indoor environments

International Journal of Web Information Systems ◽

10.1108/ijwis-05-2018-0039 ◽

2018 ◽

Vol 14 (4) ◽

pp. 402-422 ◽

Cited By ~ 1

Author(s):

Sultan Alamri

Keyword(s):

Data Management ◽

Indoor Environments ◽

Content Type ◽

Spatial Objects ◽

Current Trends ◽

Outdoor Spaces ◽

Future Challenges ◽

Different Shapes ◽

The Impact ◽

Indoor Spaces

Purpose With the rapid development of the indoor spaces positioning technologies such as the radio-frequency identification (RFID), Bluetooth and WI-FI, the locations of indoor spatial objects (static or moving) constitute an important foundation for a variety of applications. However, there are many challenges and limitations associated with the structuring and querying of spatial objects in indoor spaces. The purpose of this study is to address the current trends, limitations and future challenges associated with the structuring and querying of spatial objects in indoor spaces. Also it addresses the related features of indoor spaces such as indoor structures, positioning technologies and others. Design/methodology/approach In this paper, the author focuses on understanding the aspects and challenges of spatial database managements in indoor spaces. The author explains the differences between indoor spaces and outdoor spaces. Also examines the issues pertaining to indoor spaces positioning and the impact of different shapes and structures within these spaces. In addition, the author considers the varieties of spatial queries that relate specifically to indoor spaces. Findings Most of the research on data management in indoor spaces does not consider the issues and the challenges associated with indoor positioning such as the overlapping of Wi-Fi. The future trend of the indoor spaces includes included different shapes of indoors beside the current 2D indoor spaces on which the majority of the data structures and query processing for spatial objects have focused on. The diversities of the indoor environments features such as directed floors, multi-floors cases should be considered and studied. Furthermore, indoor environments include many special queries besides the common ones queries that used in outdoor spaces such as KNN, range and temporal queries. These special queries need to be considered in data management and querying of indoor environments. Originality/value To the best of the author’s knowledge, this paper successfully addresses the current trends, limitations and future challenges associated with the structuring and querying of spatial objects in indoor spaces.

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