Through the evolving phases of the COVID-19 pandemic, most of us have had to consider, wonder, and worry how safe we or our personal contacts are when riding in vehicles with other people. The resulting decisions about whether to ride or work on a mode of transportation have far-reaching impacts: on individuals’ income, education, and social life, and, collectively, on transportation equity, road congestion, pollution, and greenhouse gas emissions. A new study from ITS-Davis will help researchers, transportation service providers, policymakers, and the public determine how well different design features in vehicles—such as ventilation and physical barriers—can prevent transmission of COVID-19 and other contagious diseases.
The study provides a comprehensive classification system for existing and proposed design strategies for vehicles that are used by multiple individuals at the same time (“pooled modes”) or one after another (“shared modes”). After conducting a literature search, the researchers classified design elements in modes including buses, trains, subways, ride-hailing cars and taxis, airplanes, ferries, and shared cars, bikes, and scooters.
The classification includes the following 12 categories:
The published study includes an illustrated guide to these categories in a downloadable appendix, and it classifies 12 mechanisms through which each of the above strategies work, such as by physical distancing or increased air exchange.
A second part of the study is a survey of experts’ opinions on which design strategies may be most effective for reducing COVID transmission and where gaps in knowledge remain. The experts included physicians, engineers, epidemiologists, and social scientists with public health and communications backgrounds. Not surprisingly, they prioritized strategies that worked through increased air exchange, air flow, and air cleaning. The social scientists also emphasized the importance of affecting perceived safety, through education and communications, to make riders aware of strategies that are unfamiliar or, like air filtration, not visible.
Research and guidance on effective measures to reduce disease transmission on shared and pooled transportation has been published. However, much of the guidance focuses on behavioral rather than design interventions. And much of the design guidance has been industry specific, coming from disparate sources, such as the Centers for Disease Control, Department of Transportation, Occupational Health and Safety Administration, and American Society of Heating, Refrigerating, and Air-Conditioning Engineers. The new classification system builds on the earlier work and aims to make future research and guidance more widely applicable and robust.
A clear classification system should allow for a better understanding and comparative evaluation of a multitude of design possibilities. Evaluating which strategies are most effective and how they are perceived by the public can inform budgeting decisions by transportation providers and help raise ridership on pooled and shared modes. Many of these modes are key to transportation equity, employment of essential workers, and reduced greenhouse gas emissions.
Seth Karten is a science writer at ITS-Davis.
Angela Sanguinetti is a research environmental psychologist at ITS-Davis.
Beth Ferguson, Assistant Professor in the Department of Design at UC Davis, contributed significantly to the study described here as a co-principal investigator with Dr. Sanguinetti.
The study was made possible through funding received by the University of California Institute of Transportation Studies from the State of California through the Road Repair and Accountability Act of 2017 (Senate Bill 1).