Airborne transmission

This research aims to evaluate ventilation performance on airborne transmission in buildings, by analyzing the effect of different ventilation configurations and flow rates on contaminant removal effectiveness

Airborne transmissions take place as a transport of virus or bacteria via the aerosol flow in rooms. The distribution of aerosols tends to be evenly distributed if the flow in the room is fully mixed. The aerosols distribution will be different if the room air is stratified. A vertical temperature distribution may create stratified layers with either lower or higher concentrations of exhalation from the infected person.

The importance of ventilation of spaces for occupants’ health has been known for many years. Ancient Egyptians used natural ventilation to remove dust and thus to reduce respiratory diseases of stone carvers working indoors (Janssen 1999). In the past ventilation has been used to reduce airborne transmission of respiratory generated infectious agents in buildings.

Airborne exposure has been highlighted during the COVID-19 pandemic as a probable infection route. This experimental study investigates different protection methods at an office workstation, where the concentration characteristics are studied under mixing ventilation conditions. The protection methods were the room air purifier, personal air purifier, face mask, and workstation partition panels. In experiments, the breathing machine, nebulizer, and syringe pump were used to generate an aerosol distribution of paraffin oil in the room.

Building system engineering can help decrease the risk of being infected by the aerosol which contains virus-laden droplet nuclei. Many techniques can help decrease the concentrations of particles. This paper focuses on the economic renovation of the existing ventilation system of a public commercial space, a small meeting room in Kuijpers, Leiden, to decrease airborne transmission of respiratory infectious diseases.

Airborne transmission has been widely proven to be the main means of contagion of SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) , as multiple studies have established (Greenhalgh et al., 2021; Miller et al., 2021; Lidia Morawska & Cao, 2020; Tang et al., 2021; World Health Organization, 2021), Furthermore, the main documented COVID-19 outbreaks have occurred indoors (Qian et al., 2021; Randall et al., 2021; Wang et al., 2022), with medium and long-range transmission —beyond 1.5 m— as a especially relevant transmission way in poorly bad ventilated spaces (Li, 2021; Z.