Citizen-Science Technology for Healthy Living at Home - Abstract Human exposure to air pollution is the leading environmental risk factor for premature morbidity and mortality worldwide and, in the United States (U.S.), people of color suffer from many diseases associated with exposure to air pollution at higher rates than white people. Our understanding of human exposure to air pollution is based largely on measurements of outdoor pollutant concentrations and a multitude of studies have found that, following decades of discriminatory housing and land-use policies, people of color are more likely to live in U.S. neighborhoods with higher concentrations of outdoor air pollution; however, outdoor air pollution data do not capture the full picture of human exposure. People living in the U.S. spend most of their time indoors at home and prior studies have found that in-home air pollutant concentrations—which, being a combination of pollution from outdoor and indoor sources, are also likely to be impacted by the aforementioned discriminatory policies— tend to be better-correlated with personal exposures than outdoor concentrations. In-home air pollution is rarely characterized due to the cost and complexity of setting up large, noisy, finicky monitors in private residences. The goal of this Phase II SBIR project is to reduce the amount of air pollution U.S. residents are exposed to at home by making characterization of in-home air quality easy; affordable; useful to home occupants; and widespread enough to influence local-, state-, and national-level policies. The first aim of this project is to develop a small, quiet, easy-to-use “Home Health Box” (HHB) that measures indoor concentrations of particulate matter, volatile organic compounds, carbon dioxide, and nitrogen dioxide using a combination of low-cost sensors and high-fidelity integrated samplers. The HHB is designed to eliminate the need for an air quality professional to go to the home; once the HHB is delivered, an occupant simply needs to set it in a central location, plug it in, and switch it on. Data collected by the HHB will undergo automated analyses, be reviewed by an air quality professional, and then be synthesized into a report that will (a) compare measured pollutant levels to guidelines, (b) describe potential pollution sources, and (c) suggest affordable actions that occupants could take to improve their in-home air quality. The second aim of this project is to evaluate whether HHB sampling and subsequent receipt of a personalized “Home Health Report” (HHR) helps households improve their in-home air quality over time. A racially- and ethnically-diverse group of households will be recruited in partnership with healthcare providers and community organizations in Denver and Chicago. Homes will be randomized into intervention and control groups. Homes in both groups will receive three, one-week HHB deployments spaced six weeks apart. After each of the first two deployments, homes in the intervention group will receive a HHR. We will (a) investigate whether and how air quality changes over time in control and intervention homes and (b) survey intervention households on the utility of the Home Health Reports. All homes will receive a HHR at the end of the study.