Particulate matter air pollution is the leading environmental risk factor of cardiovascular disease and is increasing in the Western United States due to more frequent and severe wildfires. Older adults are particularly susceptible to both air pollution exposures and the development of cardiovascular disease, and the older adult population in the United States is rapidly growing. Given the converging threats of worsening air quality and an aging population, this clinical trial will evaluate a novel, multifaceted indoor air quality intervention to improve cardiovascular health outcomes among older adults in the wildfire-impacted state of Montana.