ABSTRACT
The COVID-19 pandemic has refocused attention to the significance of indoor air quality and how air moves during the circulation process. Contaminants, especially aerosols (≤ 5 µm), remain airborne for prolonged periods and travel long distances increasing the risk of infection to occupants. This study investigated the movement of air and respiratory particles in a clinical setting and an isolation system using computational fluid dynamics. The ventilation system distributes a combination of outdoor and indoor air to reduce energy consumption. The recirculated air carries contaminants smaller than 1 µm, which are distributed to other spaces in the building, increasing the risk of infection to other occupants. Therefore, the efficacy of an air-sterilization unit that integrates with a building air handling system was examined. It was observed that a larger percentage of aerosols were exhausted compared to droplets, as larger particles deposit on surfaces under the influence of gravity. Using the air sterilization unit reduced the pathogen concentration in the clinical setting by 25%. The air sterilization system had a significant impact when used in an isolation system with a negative pressure and a positive pressure room. Contaminants from the negative pressure room were distributed to the positive pressure room with the conventional ventilation system. However, sterilizing the recirculated air ensured complete safety of the patient (or other occupants) in the positive pressure room. The findings of these studies can be generalized to any scenario where a centralized ventilation system is employed for thermal comfort and air quality control. © 2022 Begell House Inc.. All rights reserved.
ABSTRACT
The COVID-19 pandemic has shown that airborne pathogens and viruses have a detrimental impact on the health and well-being of an individual in an indoor space. Respiratory particles are released as droplets of varying velocities and diameters, where smaller droplets (aerosols) linger in air for prolonged periods, increasing the infection risk of individuals in an enclosed space. The pandemic has raised concerns regarding the safety of musicians due to respiratory particles released through woodwind and brass instruments. A collaboration with the Buffalo Philharmonic Orchestra was pursued to assess the risk of infection and develop strategies to mitigate the spread of respiratory particles using computational fluid dynamics. A coupled Eulerian-Lagrangian modeling approach was employed to examine the airflow patterns and airborne particle pathogen transport induced by the musicians in the music hall. The investigation considered three brass instruments (trumpet, tuba, trombone), without and with a bell covering. It was observed that the dispersion of particles for each instrument depended on the bell design and orientation of the instrument. For example, the trumpet produced a higher concentration of respiratory particles compared to a tuba, which has its tubing wrapped. Additionally, the effect of using bell covers (cloth covering on the opening of the brass instruments) showed that the covers reduced the number of pathogens escaping the instruments by capturing large respiratory particles and reducing the escaping velocity of small particles. Reduced particle velocities at the instrument opening meant that the particles traveled shorter distances, which helped mitigate the spread of virus in the music hall. Moreover, the efficacy of using Plexiglas partitions on the sides and in front of the musicians limited the transmission of pathogens from one musician to another. Overall, the findings of this study helped strategize the location of musicians based on the type of instruments being played and the operating conditions in the music hall to decrease the airborne transmission of the novel Coronavirus. © 2021 by ASME.
ABSTRACT
Quality of democratic arrangements does matter. This kind of conceptual breakthrough has been made through painfully engagement with the nonphilosophical area of inquiry arisen by the COVID-19 pandemic. The pandemic has dramatically emphasized that health is a highly political domain. No surprise then that it made possible to challenge common thought about democratic procedures in political theory that considers procedure-independent standards suspicious. Therefore it is fair to state that the COVID-19 pandemic has taken the quality of democratic outcomes back on center stage in the debate in political theory, which has been dominated by fair proceduralism's claim not to refer to any procedure-independent standards of good political decisions. The aim of this paper is to justify the legitimacy and authority of public health policies on the basis of arguments that do not simply are a matter of their being democratic. In the first part, I want to display and criticize the idea that proceduralism's not getting one's hands dirty with the substance of decisions and remaining neutrally adherent only to procedures is untenable in the present case. Having criticized democratic theories that want to restrict themselves to purely procedural values, in the second part I will focus on the idea of knowledge and make explicit its characters of being practical and shared. Eventually, it will help to have one example. M-Health will show that many valuable insights would be incompatible with the restrictions of the proceduralism. Philosophical consideration of health will combine epistemic issues with political ones triggered by technology and sharpened by the COVID-19 pandemic.