Air Quality in Transit Buses (2023)
Chapter: Introduction
Introduction
“Air Quality in Transit Buses” was organized by the Transportation Research Board’s (TRB’s) Transit Cooperative Research Program (TCRP) under TCRP Project E-13 as part of its series of convening activities titled “TCRP Insight Events.” This event explored how air quality inside transit vehicles, especially buses, may contribute to the spread of infections, including COVID-19.
The COVID-19 pandemic has brought air quality to the forefront for the transit industry. The pandemic has required an increased understanding of infectious disease in confined spaces and the role of droplets and particles in transmission. A combination of experiments, models, and simulations in fluid dynamics has been employed to understand how aerosols move in a space containing people. Research has shown that the smaller aerosol sizes have an increased viral load relative to larger aerosols. This finding has led to verification studies on increased ventilation with outdoor air; better heating, ventilation, and air-conditioning (HVAC) filters able to capture smaller particles of indoor air, and ultraviolet light (UV) technologies for killing pathogens.
“Air Quality in Transit Buses” sought to bring together representatives from the transit sector, along with other experts engaged in transit operations, air quality technology, and infectious disease. This TCRP Insight Event took place virtually on June 21–22, 2022. Preparations included a thorough literature review, which served to define the state of understanding of infectious disease and its impact on the transit industry and to identify notable thought leaders and practitioners within the industry. Several of these thought leaders and practitioners were then selected to serve on the planning committee for the event. Others were chosen as presenters.
The event led off with an overview of infectious disease and how it moves in an enclosed space and opportunities and challenges facing the transit industry. A series of presentations and panel discussions on filtration, ventilation, and clean air metrics followed. The program agenda for the event is provided in Appendix A.
More than 150 people from around the country registered for the event. Registrants’ professional affiliations included transit systems; federal, state, and local government; consulting; law; finance; technology; and more. A list of registrants is provided in Appendix B. At the conclusion of the event, participants were asked to complete a feedback survey. A summary of the responses is provided in Appendix C.
Presentations from “Air Quality in Transit Buses” and the results of the literature search are available on the TCRP Insight Event web page at https://www.nationalacademies.org/event/06-21-2022/trb-tcrp-insight-event-air-quality-in-transit-buses. Readers who are interested in more information can e-mail the TCRP Senior Program Officer for the event, Mariela Garcia-Colberg, at MGColberg@nas.edu.
TCRP is an industry-driven applied research program that develops near-term, practical solutions to problems faced by transit operators. TCRP is managed by TRB, a part of the National Academies of Sciences, Engineering, and Medicine, and is sponsored by the Federal Transit Administration (FTA) in cooperation with the American Public Transportation Association. TCRP Insight Events are forums that foster dialogue between professionals across sectors, institutions, and industries. TCRP Insight Events convene transit industry leaders and subject matter experts in various fields to encourage discussion and promote broader and deeper insight on topics of significance to transit operators. These in-depth gatherings are designed to promote communication and collaboration, foster innovation, and help identify areas of future interest and research, especially for topics of emerging importance.
