In-duct UVGI systems for air disinfection against COVID-19 in buildings

近几个月来，越来越多的证据表明，SARS-CoV-2可以通过空气传播。应控制通过空气接触病毒，以减少这种传播途径。最近的热浪说明了对条件良好的空间的需求。由于消除界限已提上议程，气温正在上升，确保有条件空间，特别是聚集空间的公共卫生是一项优先事项。然而，大多数空间的运营商通常负担不起专门的维修人员。因此，任何暖通空调空气消毒解决方案都必须是独立的、具有成本效益的、可靠的、低维护的。

In recent months, more evidence indicates that SARS-CoV-2 can be transmitted through the air. Airborne exposure to the virus should be controlled to mitigate such a transmission path. Recent heatwaves illustrated the need for well-conditioned spaces. As deconfinement is on the agenda and temperature is on the rise, ensuring public health at conditioned spaces, particularly at congregate spaces, is a priority. However, operators of most spaces usually could not afford a dedicated maintenance crew. Therefore, any HVAC air disinfection solutions must be self-contained, cost-effective, dependable, and low maintenance. UVC radiation effectively inactivates airborne microorganisms by breaking bonds in RNA and thus preventing replication of the microorganisms. In-duct ultraviolet germicidal irradiation (UVGI) systems treat moving air streams in HVAC systems is proposed. Collaborating with an HVAC design company (Les Services Polarbear), this project will address the challenge in designing in-duct UVGI systems: how to ensure the steady and consistent delivery of targeted UVC dose under constantly changing conditions of the in-duct air stream. The project will conduct a simulation-based experiment to test the impact of temporal and spatial dependent variations in in-duct conditions of the air stream such as temperature, relative humidity, and airflow rate on UVC dose. Les Services Polarbear, will collect the performance data of on-going projects to validate the simulation-based experiment. The validated results will provide a best practice guide for the HVAC industry in retrofitting existing HVAC systems with in-duct UVGI systems. The practical solution helps cut one likely path of transmission and hence increases Canada's preparedness in facing future infectious outbreak.