Project Abstract Wildfire smoke is an increasing public health concern with episodes extending into the school year. Children are vulnerable to health impacts of fine particulate matter, a major component of wildfire smoke. Yet data to adequately understand and inform essential public health decision-making on school indoor air pollution during wildfire events are lacking. This project seeks to establish a scientifically-sound toolkit for schools to estimate fine particulate matter infiltration in classrooms that can be done prior to poor air pollution episodes (preparedness), capitalizing on advances in low-cost sensor technology. A key objective is to understand school decision-makers’ perspectives on data needs in order to design toolkits for using low-cost sensors that produce data that are useful to school, air quality, and local health personnel and provide confidence for meaningful decision-making. Low-cost fine particulate matter sensors will be placed outdoors and in multiple indoor locations at 6 schools in regions impacted by fine particulate matter, including wildfire smoke, for at least 6 months. To calibrate sensor data, during baseline and poor air quality periods, sensors will temporarily be paired with gold standard fine particulate matter gravimetric samplers. An analysis accounting for the shared temporal trend will be used to quantify variation in fine particulate matter between indoor spaces within- school, and assess how the variation changes between baseline and poor air quality periods. Room visits to monitor air quality of various frequencies and durations will be simulated and compared to long-term average trends to assess the accuracy of hypothetical short term air monitoring visits that may be practical for schools. Study results will be shared with school, local health, and air quality personnel during individual interviews. Interviews will focus on personnel perspectives on the study results and on adequate accuracy for data to support decision-making (e.g. avoid certain classrooms during wildfire smoke, add air cleaners), and feasibility of air monitoring. Personnel perspectives will inform the design of 2 toolkits that include manuals for schools to use that vary in complexity and accuracy. The end-user informed toolkits will undergo re-test in 2 new schools, and further discussion with end-users will yield 2 final evidence-based practical toolkits. This research promotes NIEHS’ vision to prevent disease and disability by enabling schools to mitigate children’s exposures to fine particulate matter, and supports Strategic Plan theme 2: Promoting Translation – Data to Knowledge to Action. A complementary training plan builds on the applicant’s foundational experience in air pollution sensor applications and community-engaged research with Tribal Nations and underserved communities, and supports transition to independent investigator. The Sponsor and Co-Sponsor are established research collaborators as well as establi...