Addressing indoor air quality (IAQ) is essential for reducing respiratory disease risks. In this commentary, we highlight the need for increased connections between typically siloed engineering and health disciplines to tackle remaining IAQ knowledge gaps that, if closed, would enhance IAQ applications and health. We provide actionable insights for policymakers, building designers, and funding agencies, recommending multidisciplinary research to support (1) increasing understanding of the complex and multifactorial variables in human infection, (2) using physical and mathematical models to understand disease transmission, and (3) determining the effectiveness of layered interventions in different environments. Addressing these knowledge gaps will help in the delivery of cost-effective IAQ solutions that reduce infectious disease risks in workplaces, schools, homes, and other indoor environments.
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